HemAcure and Sernova, A Big Deal

Richard (Rick) Mills
Ahead of the Herd

As a general rule, the most successful man in life is the man who has the best information

When most of us suffer a cut cells in the blood, called platelets, go to where the cut is, plug the hole and stop the bleeding. While the platelets are plugging the hole they release chemicals that attract more of the ‘sticky’ platelets and twelve (numbered using Roman numerals I through XII) proteins in the blood known as clotting factors are activated. These proteins mix with the platelets to form fibers which make the clot stronger and stop the bleeding.

Having too little of factors VIII (8) or IX (9) is what causes hemophilia. A person with hemophilia will lack only one factor, either factor VIII or factor IX, but not both. There are two major kinds of hemophilia: hemophilia A, which is a factor VIII deficiency; and hemophilia B, which is a factor IX deficiency.

Hemophilia is a genetic disorder which means it’s the result of a change in genes that was either inherited (passed on from parent to child) or occurred during development in the womb. Although it is mostly passed down from parents to children, about 1/3 of cases are caused by a spontaneous mutation, a change in a gene. All races and ethnic groups are equally affected by hemophilia A. The disease almost always affects males but can also affect females.

Many people believe that hemophiliacs bleed a lot from minor cuts but external wounds are usually not that serious. Much more serious is internal hemorrhaging that can take place in joints (especially knees, ankles and elbows) and into tissues and muscles. Bleeding can also occur in vital organs putting a hemophiliac’s life in danger.

Although effective treatment of the symptoms is available, there is no cure for hemophilia A at present and therapy has to be individualized to specific patients. Patients have to get lifelong infusions with recombinant factor VIII (rFVIII) several times a week to compensate for the missing clotting factor.

The global total hemophilia market was valued at US$ 9.3 billion in 2015. Approximately 20,000 people in the United States, 10,000 in Europe and approximately 2,500 in Canada have a moderate or severe form of hemophilia A. Annual costs for the treatment of the disease for each patient may range from US$60,000 to US$260,000 for a total cost of between $2-5B per year just in North America and Europe.

Grand View Research

The Horizon 2020 program

Horizon 2020 is the largest European Union (EU) research and innovation program ever undertaken with nearly €80 billion of funding available over the seven years between 2014 to 2020. Horizon 2020 promises breakthroughs, discoveries and world firsts by taking great ideas from the lab to the market, for example in the field of personalized medicine providing novel therapies such as gene or cell therapy.

HemAcure project, a novel personalized medicine curative therapy

An international research consortium, under the name HemAcure unites scientific academic institutions from Germany, Italy, the UK and Sernova Corp from Canada.

The following institutions are involved in HemAcure:

  • ARTTIC, a Munich-based enterprise that specializes in the management of EU-funded collaborative research projects, is in charge of project management.
  • The Department of Tissue Engineering and Regenerative Medicine of the Wuerzburg University Hospital is responsible for isolating the cells.
  • The Università del Piemonte Orientale (Italy) is developing, optimizing and performing the gene correction of the patient cells for expression of the Factor VIII therapy.
  • Scientists from Loughborough University (UK) are focussing on the manufacturing process and safety testing.
  • Sernova a Canadian public company, is responsible for conducting the preclinical safety and efficacy studies with the Factor VIII producing cells in its proprietary Cell Pouch™ using a model of hemophilia developed by consortium partner Universita del Piemonte Orientale (Italy) in preparation for clinical trials.
  • The quality management (GMP processes) is being monitored by IMS – Integrierte Management Systeme in Heppenheim, Germany. The company acts as a point of contact for international projects in the pharmaceutical and medical engineering sector.

The overall objective of the HemAcure project is to develop and refine the tools and technologies for a novel, curative ex vivo (outside the body) prepared cell based therapy to treat hemophilia A that should ultimately lead to improved quality of life for patients. The EU’s Horizon 2020 programme has stage funded the HemAcure project with €5.5 million (Cdn$8.06M, US$6.3). The most recent tranche of funding has just been approved based on the encouraging results to date.

The consortium’s idea: A personalized medicine solution using the patients’ own cells (remember each patient has to have individualized therapy) which are genetically modified outside the body to produce the missing clotting factor using precursor cells of endothelial cells flowing in the bloodstream. After modification these cells are transplanted back into the patient’s body in Sernova Corp’s Cell Pouch™.

After Sernova’s Cell Pouch™ is implanted in the body and forms its unique vascularized tissue chambers, the genetically modified cells are then transplanted into the vascularized chambers and are expected to continuously produce the clotting factor and release it into the bloodstream for a long period of time. This should mitigate the disease’s impact noticeably, increase the patients’ quality of life and reduce the overall cost of therapy.

Sernova

Sernova Corp. (TSX-V: SVA) (OTCQB: SEOVF) (FSE: PSH), is a Canadian publically traded, clinical stage, regenerative medicine company developing an implantable, scalable device, the Cell Pouch System™ and therapeutic cells for the treatment of diseases such as diabetes, and hemophilia.

Sernova’s Cell Pouch™ forms a natural vascularized environment for long-term survival and function of the therapeutic cells which release into the bloodstream required but missing proteins or hormones.

Sernova’s Cell Pouch™ technology would be beneficial if it provided a simple reduction in the number of therapeutic injections a patient must take; however, there is the possibility that it could even essentially ‘cure’ the disease through natural release and regulation of the therapeutic proteins or hormones.

“Sernova has developed its proprietary highly innovative Cell Pouch technologies for the placement and long-term survival and function of immune protected therapeutic cells. It has proven to be safe and efficacious in multiple small and large animal preclinical models and has demonstrated safety alone and with therapeutic cells in a clinical trial in humans for another therapeutic indication (diabetes – editor). We believe the Cell Pouch platform is the first such patented technology proven to become incorporated with blood vessel enriched tissue-forming tissue chambers without fibrosis for the placement and long-term survival and function of immune protected therapeutic cells.” Sernova News Release, Marketwire – July 24, 2017

Sernova is today a relatively unknown pure regenerative medicine play that has partnered their Cell Pouch™ with a network of academic cell therapy research and development partners. Below is a HemAcure consortium approved news release issued by Sernova Corp. on Monday July 24, 2017.

It’s your authors opinion ‘relatively unknown’ is a term that will shortly no longer apply to Sernova Corp.

Sernova-HemAcure Consortium Announce Significant Progress in Development of ‘First in World’ Regenerative Medicine Therapy for Treatment of Hemophilia A Patients

Breakthrough scientific progress is made in development of a disruptive personalized regenerative medicine therapy within Sernova’s Cell Pouch(TM) for treatment of Hemophilia A validated by European Commission’s confirmation of next stage of funding of the €5.6Million EU Horizon 2020 Grant Award to the HemAcure Consortium

LONDON, ONTARIO – (Marketwire – July 24, 2017) – Sernova Corp. (TSX-V: SVA) (OTCQB: SEOVF) (FSE: PSH), a clinical stage regenerative medicine company, announced today significant scientific progress achieved in the development of a ‘first in world’ personalized regenerative medicine therapy for the treatment of Hemophilia A patients by the HemAcure Consortium and confirmation of the second phase of funding of the Consortium by the European Commission.

The therapy being developed by international scientific Consortium members consisting of three European academic institutions, an enterprise for quality management and Sernova Corp is to treat severe Hemophilia A, a serious genetic bleeding disorder caused by missing or defective clotting factor VIII in the blood stream. This therapy consists of Sernova’s implanted Cell Pouch(TM) device transplanted with therapeutic cells, corrected to produce Factor VIII at a level sufficient to significantly reduce the side effects of the disease and improve patient quality of life.

“The international HemAcure Consortium team members are pleased with the ground breaking scientific advances achieved at this point and are on track for this regenerative medicine solution to advance into human clinical evaluation,” remarked Dr. Philip Toleikis, Sernova President and CEO.

Toleikis added, “Sernova’s Cell Pouch platform technologies are achieving important world first milestones in both diabetes and now hemophilia, two significant clinical indications which are being disrupted by its regenerative medicine approach aimed at significantly improving patient quality of life.”

“We are thrilled with the approval by the European Union of the next stage of funding for the HemAcure program based on our quality interim report. This is a strong validation of the Consortium’s dedication and teamwork and the importance of this regenerative medicine approach,” said Dr. Joris Braspenning, HemAcure Program Coordinator.

In summary, the following ground-breaking developments have been achieved by the Consortium:

  • A reliable procedure has been implemented to isolate and maintain required endothelial cells from a sample of the patient’s blood.
  • Using a novel gene correction process, the cells have been corrected and tuned to reliably produce the required Factor VIII to treat Hemophilia A.
  • The cells have been successfully scaled up to achieve the required therapeutic number, and cryopreserved for shipping and future transplant into the implanted Cell Pouch.
  • A preliminary study confirmed survival of the Factor VIII corrected human cells injected into the hemophilia model, achieving sustained therapeutic Factor VIII levels. This preliminary work is being used to aid in dosing of these cells in the Cell Pouch.
  • Safe Cell Pouch surgical implant and cell transplant procedures have been developed in the hemophilia A model in preparation for use in hemophilia patients.
  • Development of Cell Pouch vascularized tissue chambers suitable for Factor VIII producing cell transplant has been demonstrated in the hemophilia A model, expected to mimic the predicted findings in human patients.
  • In combination, this work is in preparation for safety and efficacy studies of the human hemophilia corrected Factor VIII producing cells in the Cell Pouch in a preclinical model of hemophilia.

This combination of advances by the HemAcure team represents a ‘first in world’ achievement towards developing a regenerative medicine therapy for the treatment of severe hemophilia A patients.

“In this regard, these fundamental advancements have set the stage for further optimization and implementation of cell production processes under controlled GMP conditions,” stated Martin Zierau, IMS member consortium team leader responsible for coordination of GMP processes.

With Factor VIII corrected cells, studies are ongoing to optimize cell dosing within the Cell Pouch and for study of safety and efficacy of hemophilia corrected Factor VIII cells in the hemophilia model. These studies are in support of the current extensive regulatory package already assembled for the Cell Pouch in anticipation of human clinical evaluation of the Cell Pouch with hemophilia corrected Factor VIII producing cells.

A big deal

Any discussions regarding advancing HemAcure’s plan, and more funding from Horizon 2020, had to be centered around success in these three areas:

  • CELLS ARE PRODUCING FACTOR VIII: The Consortium has successfully developed the process for isolating and maintaining the required cells from a sample of patient’s blood. Using a special technique these cells have been corrected and tuned to produce Factor VIII on a constant basis.
  • CORRECTED CELLS HAVE BEEN SCALED UP: The corrected cells have then been multiplied to demonstrate that the required number of cells can be produced. After testing, batches of corrected cells have been frozen, stored for later transplantation and successfully shipped, thawed and recovered. With further optimization and GMP production, this being the process anticipated to be used for future treatment of patients with hemophilia A.
  • CELLS PRODUCING THERAPEUTIC BLOOD LEVELS OF FACTOR VIII: In further preclinical tests, in a preliminary study, Factor VIII producing cells have been shown to produce therapeutic blood levels of Factor VIII. Studies have already shown that the Cell Pouch can produce vascularized tissue chambers in the hemophilia model and further studies will optimize dosing of hemophilic patient corrected cells that will then be transplanted into the Cell Pouch™ for evaluation of safety and efficacy in the preclinical model of hemophilia.

Conclusion

Being that all the companies in the HemAcure consortium are private, except SVA, and that they plan on ‘bringing breakthroughs, discoveries and world firsts from the lab to the market’ might not Sernova be a great way to leverage this in your portfolio?

And SVA is no one trick pony, the company is a leader in the regenerative space with their Cell Pouch™ and upon FDA clearance plan to initiate clinical trials in the United States for diabetes – expected to start patient enrollment this fall.

Add in developing local immune protection technology within the Cell Pouch™ and the company’s very own glucose responsive stem cell technology, you can see why your author thinks Sernova Corp might just be the best regenerative medicine pure play out there.

All of these reasons are why Sernova Corp. is on my radar screen. Is SVA on yours?

If not, maybe it should be.

Richard (Rick) Mills

aheadoftheherd.com

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New Therapeutic Approach for Difficult-to-Treat Subtype of Ovarian Cancer Identified

Scientists from The Wistar Institute demonstrate how a mutation in ovarian clear cell carcinoma can be exploited to design a targeted treatment.

A potential new therapeutic strategy for a difficult-to-treat form of ovarian cancer has been discovered by Wistar scientists. The findings were published online in Nature Cell Biology.

Ovarian clear cell carcinoma accounts for approximately 5 to 10 percent of American ovarian cancer cases and about 20 percent of cases in Asia, ranking second as the cause of death from ovarian cancer. People with the clear cell subtype typically do not respond well to platinum-based chemotherapy, leaving limited therapeutic options for these patients.

Previous studies, including those conducted at The Wistar Institute, have revealed the role of ARID1A, a chromatin remodeling protein, in this ovarian cancer subtype. When functioning normally, ARID1A regulates expression of certain genes by altering the structure of chromatin – the complex of DNA and proteins in which DNA is packaged in our cells. This process dictates some of our cells’ behaviors and prevents them from becoming cancerous.

“Conventional chemotherapy treatments have proven an ineffective means of treating this group of ovarian cancer patients, meaning that alternative strategies based on a person’s genetic makeup must be explored,” said Rugang Zhang, Ph.D., professor and co-program leader in Wistar’s Gene Expression and Regulation Program and corresponding author of the study. “Therapeutic approaches based on the ARID1A mutation have the potential to revolutionize the way we treat these patients.”

Recent studies have shown that ARID1A is mutated in more than 50 percent of cases of ovarian clear cell carcinoma. Mutations of ARID1A and the tumor suppressor gene TP53 are mutually exclusive, meaning that patients with a mutation of ARID1A do not also carry a mutation of TP53. Despite this, the function of TP53, which protects the integrity of our genome and promotes programmed cell death, is clearly impaired as patients with the disease still have a poor prognosis.

In this study, Zhang and colleagues studied the connection between ARID1A and histone deacetylases (HDACs), a group of enzymes involved in key biological functions. They found that HDAC6 activity is essential in ARID1A-mutated ovarian cancers. They were able to show that HDAC6 is typically inhibited by ARID1A, whereas in the presence of mutated ARID1A, HDAC6 levels increase. Because HDAC6 suppresses the activity of TP53, therefore inhibiting its tumor suppressive functions, higher level of HDAC6 allow the tumor to grow and spread.

Using a small molecule drug called rocilinostat that selectively inhibits HDAC6, the Zhang lab found that by blocking the activity of the enzyme in ARID1A-mutated cancers, they were able to increase apoptosis, or programmed cell death, in only those tumor cells containing the ARID1A mutation. This correlated with a significant reduction in tumor growth, suppression of peritoneal dissemination and extension of survival of animal models carrying ARID1A-mutated ovarian tumors.

“We demonstrated that targeting HDAC6 activity using a selective inhibitor like rocilinostat represents a possible therapeutic strategy for treating ovarian clear cell carcinoma and other tumors impacted by mutated ARID1A,” said Shuai Wu, Ph.D., a postdoctoral fellow in the Zhang lab and co-first author of the study. “Inhibitors like the one we used in this study have been well-tolerated in clinical trials, so our findings may have far-reaching applications.”

Concurrent Chemotherapy, Proton Therapy Improves Survival in Patients with Advanced Lung Cancer

For patients with advanced, inoperable stage 3 lung cancer, concurrent chemotherapy and the specialized radiation treatment, proton therapy, offers improved survival compared to historical data for standard of care, according to a new study from The University of Texas MD Anderson Cancer Center.

The research, published in JAMA Oncology, reported an overall survival (OS) of 26.5 months. In contrast, the historical OS rate with standard of care concurrent chemotherapy and traditional radiation was 16 months at the time when the study was designed.

The findings are the final results of the single institution, Phase II study and represent the longest follow-up to date of stage 3 lung cancer patients who have received proton therapy, said Joe Y. Chang, M.D., professor, Radiation Oncology and the study’s corresponding author.

Lung cancer is the leading cause of cancer death in both men and women in the U.S. According to the American Cancer Society, more than 222,500 people will be diagnosed and 155,870 will die from the disease in 2017, with the majority of patients still being diagnosed when the disease is in an advanced stage.

“Advanced lung cancer patients with inoperable disease traditionally have been treated with concurrent chemotherapy and conventional photon radiation therapy. However, the therapy can be very difficult for patients due to associated toxicities and because many patients are also dealing with comorbidities,” explained Chang.

Proton therapy is an advanced type of radiation treatment that uses a beam of protons to deliver radiation directly to the tumor, destroying cancer cells while sparing healthy tissues. Protons enter the body with a low radiation dose and stop at the tumor, matching its shape and volume or depth. They deposit the bulk of their cancer-fighting energy right at the tumor, thereby reducing the dose to cardiopulmonary structures, which impacts the toxicity, functional status, quality of life and even survival for patients, explained Chang.

“With our study, we hypothesized that proton therapy would offer a survival benefit to patients and reduce treatment-associated toxicities, which can be very serious,” he said.

The study opened at MD Anderson in 2006; in this research, Chang and his colleague report on the study’s five-year results.

For the prospective Phase II trial, 64 patients with inoperable, Stage III non-small-cell lung cancer were enrolled. The study’s primary endpoint was OS. The researchers hypothesized that the median OS would increase from historical data of 16 months on standard therapy to 24 months. Secondary endpoints included distant metastasis and local and regional recurrence rates. Toxic effects of treatment in both the acute and late settings also were analyzed.

Median follow up was 27.3 months for all patients, and 79.6 months for alive patients. At five years, the median OS was 26.5 months, and the corresponding five-year OS was 29 percent. Median progression-free survival was 12.9 months, with a five-year progression-free survival of 22 percent.

In sum, 39 patients experienced a relapse, with distant sites representing 62 percent of all recurrences. Local and regional recurrence rates were low, 16 percent and 14 percent, respectively.

Among the acute and late toxic effects diagnosed in patients were: esophagitis, pneumonitis and cardiac arrhythmia. Of note, said Chang, no patients developed the most severe, or grade five, toxicities, as seen in patients who receive standard of care.

Chang noted his study is not without limitations. Of greatest significance: the study was designed more than a decade ago. While the study’s survival, recurrence rates and toxic effects are still favorable when compared to rates associated with the most advanced traditional photon radiation therapy, intensity modulated radiation therapy (IMRT), technology to diagnose and stage the disease, as well all treatment modalities have significantly improved.

“When the study opened, PET imaging had just been approved for lung cancer staging. The image quality was poor and didn’t include a CT component in most facilities across the country,” said Chang. “Obviously, the technology has improved dramatically over the last decade and has made a significant impact on diagnosis and staging. Also, delivery of both the conventional intensity-modulated radiation therapy (IMRT) and proton therapy (IMPT), have improved, thereby reducing side effects for both treatment modalities.”

For example, MD Anderson proton therapy patients with advanced lung cancer now can receive IMPT. The technique uses an intricate network of magnets to aim a narrow proton beam at a tumor and “paint” the radiation dose onto it layer by layer. Healthy tissue surrounding the tumor is spared, and side effects are even more reduced than earlier proton delivery, said Chang. A Phase II trial studying IMPT and concurrent chemotherapy is underway. Chang also noted the advancements in cancer biology and immunotherapy and that both are important areas of research focus in combination with proton therapy.

Immune-cell numbers predict response to combination immunotherapy in melanoma

Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco researchers joined by physicians from UCSF Health. The findings provide a novel predictive biomarker to identify patients who are most likely to respond well to a combination of immunotherapy drugs known as checkpoint inhibitors — and to protect those who won’t respond from potentially adverse side effects of combination treatment.

“Combination immunotherapy is super-expensive and very toxic,” said Adil Daud, MD, director of Melanoma Clinical Research at the UCSF Helen Diller Family Comprehensive Cancer Center and senior author of the new study. “You’re putting patients at a lot of extra risk if they don’t need it, and you can adjust for that risk by knowing in advance who can benefit.”

The study, published online July 20, 2017 in Journal of Clinical Investigation Insight, describes an assay that measures the abundance of immune cells that infiltrate melanoma tumors. The findings revealed that patients who had lower levels of immune cells called T cells within their tumors benefitted most from two immunotherapy drugs in tandem. The measurements could provide clinicians with a means to predict patients who would most benefit from combination immunotherapy, the authors said.

“This is clinical research at its best,” said UCSF’s Katy Tsai, MD, a medical oncologist and lead author of the new report. “We have identified something as a predictive biomarker in melanoma, and we’re hoping to validate it in other tumor types as well.”

T cells are immune cells that patrol our body for signs of infection or other diseases, recognizing culprit cells via telltale proteins on their membranes. Our body’s normal cells carry certain proteins on their coats that act as “checkpoints,” making them invisible to T cells. But it turns out many cancer cells adopt the same trick — they cloak themselves with one of those same proteins, called PD-L1, causing T cells, which carry a complementary protein called PD-1, to mistake them as harmless. PD-L1 thus acts like a fake identification card, allowing cancer cells to live and multiply without being detected by the immune system.

Immunotherapy drugs called checkpoint inhibitors work to uncloak cancer cells by throwing a wrench in their disappearing act: these drugs block PD-L1 or PD-1, allowing T cells to recognize cancer cells as detrimental and kill them.

There are four FDA-approved checkpoint inhibitors: ipilimumab, nivolumab, pembrolizumab and atezolizumab. These drugs have been very successful in some cases, but they help only about 20 to 40 percent of patients. One of the ways doctors have improved their efficacy is by using multiple drugs at the same time. But the toxic side effects of these drugs can add up, and clinicians need to be able to correctly predict those who are most likely to respond to single drugs or combinations.

In a previous study, Daud and colleagues homed in on what makes some individuals respond well to checkpoint inhibitors that block PD-1, finding that patients whose tumors harbored high populations of T cells known as partially exhausted CD8+ cells responded well to treatment with nivolumab, an anti-PD-1 drug. Intriguingly, these cells had high levels of both PD-1 and CTLA-4, another well-known immune checkpoint protein, which is targeted by immunotherapy drugs such as ipilimumab.

In the new report, the researchers studied tumor samples from 102 melanoma patients, extracted T cells from the samples, and used cell sorting equipment to estimate the relative proportion of immune cells in the samples. The patients then underwent treatment either with only nivolumab, or with both nivolumab and ipilimumab. Finally, the researchers ran statistical tests to discover correlations among patient demographics, immune cell populations, and drug responses.

The team found that patients with high levels of exhausted T cells benefitted significantly from treatment with only a single drug. On the other hand, women and those who had liver metastases had lower number of immune cells patrolling their tumors, and responded well to the combination treatment.

“You’re pushing on two different gas pedals – PD-1 and CTLA-4,” said Daud, a member of UCSF’s Parker Institute for Cancer Immunotherapy center. “If you’re one of those patients with a low number of exhausted T cells, you have a better likelihood of benefitting from both drugs.”

The team will next explore why women have fewer T cells — and in turn, a diminished response to single immunotherapy drugs — and whether these factors could be related to age, estrogen levels, or are related to pregnancy.

The cell-counting assay developed by the researchers is time- and resource-intensive, especially because it requires fresh tumor samples and elaborate cell-sorting machines, and it is only available at UCSF. To get around these limitations, the team is now working on a more broadly applicable test that would measure the levels of PD-1 and CTLA-4 proteins — both present on T cells — in tumors and use that as a surrogate marker for immune cell count.

“In six months to a year, we should have an assay that works using fairly common, less expensive techniques,” said Daud. “And it could work on fresh, frozen or paraffin-embedded tumor blocks.” With this easier test, the researchers hope to expand their study of immune cell infiltration to other cancer types and to bigger groups of patients, both from different areas of the U.S. and internationally

New combination of anti-obesity drugs may have beneficial effects

Research conducted in the Perelman School of Medicine at the University of Pennsylvania has revealed that a unique combination of hormone-based drugs can produce enhanced weight loss in laboratory tests with obese animals. The research is to be presented this week at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB), the foremost society for research into all aspects of eating and drinking behavior.

“Imagine a drug regimen where an obese person would cycle between different drug therapies over the course of a month to achieve a greater degree of body weight loss compared to the effects achieved with either a single drug or the continuous combination of drugs,” said senior author Dr. Matthew Hayes. His team studied the combination of two different drug classes that target different hormones: amylin and glucagon-like peptide-1 (GLP-1). They found that combined treatments acted synergistically to suppress feeding and body weight. They also discovered that the weight loss effects of chronic amylin- and GLP-1-based combination therapies could be enhanced when obese lab animals are cycled through their drug treatments. “The idea of drug-cycling is nothing new,” says lead author Kieran Koch-Laskowski. “Millions of women on birth control pills, for example, already take daily pills that cycle between drug and placebo throughout the month,” she goes on to say.

Perhaps the most exciting finding of the current data coming out of Penn is the fact that the research finds these enhanced weight loss effects with a combination of drugs that are either already FDA approved or in clinical trials for metabolic diseases, “making the translational impact of our work extremely timely and highly clinically relevant!” says Hayes. The authors are now finalizing their research to demonstrate mechanically how these two hormonal systems interact to achieve greater weight loss in the hopes of fast-tracking their findings to new clinical treatments for obesity.

Identification of PTPRZ as a drug target for cancer stem cells in glioblastoma

Glioblastoma is the most malignant brain tumor with high mortality. Cancer stem cells are thought to be crucial for tumor initiation and its recurrence after standard therapy with radiation and temozolomide (TMZ) chemotherapy. Protein tyrosine phosphatase receptor type Z (PTPRZ) is an enzyme that is highly expressed in glioblastoma, especially in cancer stem cells.

The research group of Professor Masaharu Noda and Researcher Akihiro Fujikawa of the National Institute for Basic Biology (NIBB) showed that the enzymatic activity of PTPRZ is requisite for the maintenance of stem cell properties and tumorigenicity in glioblastoma cells. PTPRZ knockdown strongly inhibited tumor growth of C6 glioblastoma cells in a mouse xenograft model. In addition, the research team discovered NAZ2329, an allosteric inhibitor of PTPRZ, in collaboration with ASUBIO Pharma Co. Ltd.. NAZ2329 efficiently suppressed stem cell-like properties of glioblastoma cells in culture, and tumor growth in C6 glioblastoma xenografts. These results indicate that pharmacological inhibition of PTPRZ is a promising strategy for the treatment of malignant gliomas.

CAR T-Cell Therapy for Leukemia Leads to Remissions in Clinical Trial

In an early-phase clinical trial of an experimental immunotherapy, researchers achieved durable molecular remissions in patients with chronic lymphocytic leukemia who had failed other treatments

Researchers at Fred Hutchinson Cancer Research Center showed about 70 percent of patients with the most common adult leukemia had their tumors shrink or disappear following an experimental chimeric antigen receptor (CAR) T-cell immunotherapy.

The researchers also found that measuring genetic traces of cancer cells taken from bone marrow biopsies might be a better indicator of prognosis than the standard lymph node scan.

The Journal of Clinical Oncology published the results online July 17 of the Phase 1/2 clinical trial, which included 24 patients with chronic lymphocytic leukemia (CLL) who had failed other treatments. Most of the patients had seen their cancer progress despite treatment with ibrutinib, a targeted cancer drug approved in 2014 for CLL by the U.S. Food and Drug Administration.

This history placed them in a high-risk group that was found in previous studies to have short survival with standard therapies.

“It was not known whether CAR T-cells could be used to treat these high risk CLL patients,” said lead author Dr. Cameron Turtle, an immunotherapy researcher at Fred Hutch. “Our study shows that CD19 CAR T-cells are a highly promising treatment for CLL patients who have failed ibrutinib.”

CD19 CAR T-cells are a type of immunotherapy in which a patient’s T cells are extracted from their blood and modified in a lab to recognize CD19, a target on the surface of leukemia cells. The engineered T cells are then infused back into the patient where they multiply and hunt down and kill cancer cells.

In CLL, bone marrow makes too many abnormal lymphocytes, which are a type of white blood cell. The American Cancer Society estimates that in the U.S., there will be about 20,000 new cases and 4,600 deaths from CLL in 2017. Tests of blood, bone marrow and lymph nodes—where lymphocytes congregate to fight infection—reveal the disease.

The 24 patients participating in the study ranged in age from 40 to 73 years, with a median age of 61. They had received a median of five other therapies with as few as three and as many as nine.

Researchers found that 17 out of 24 (71 percent) of patients saw their tumors shrink or disappear following CAR T-cell therapy using the standard measure of lymph node size by CT scans four weeks after treatment.

Of side effects of CAR-T cell therapy, 20 of the 24 patients—83 percent—experienced cytokine release syndrome (grade 1-2, 18 patients; grade 4, one patient; grade 5, one patient) and 8 patients (33 percent) developed neurotoxicity (grade 3, five patients; grade 5, one patient). For the most part the side effects were reversible, but two patients had side effects severe enough to require being admitted to the intensive care unit and one of those patients died.

 (An earlier report on trial results was presented by Turtle in December at the American Society of Hematology annual meeting.)

The new paper expands on the measures used to indicate whether the CAR T-cell treatment is working.

To take a closer look to see if any cancer cells remained after treatment, the research team analyzed samples taken from some of the patients’ bone marrow four weeks after the CAR T-cell infusion. The team used a genetic test called IGH deep sequencing, which is akin to a bar code and enables researchers to track cancer cells in the body.

Turtle and his collaborators did the sequencing analysis in 12 of the patients. Seven of the 12 patients had no malignant copies. All patients without malignant copies were alive and free of disease at a median follow-up of 6.6 months after CAR T-cell infusion.

Compared with the CT scans, having no malignant gene sequences in bone marrow following CAR T-cell therapy was a better predictor of the cancer staying at bay—known as “progression-free survival,” the researchers found.

The study is the first to suggest that deep sequencing might be a superior measure for predicting outcomes four weeks after CAR T-cell therapy for CLL.

The immunotherapy team at Fred Hutch is still enrolling eligible patients with CLL, acute lymphoblastic leukemia and non-Hodgkin lymphoma for treatment on CD19 CAR T-cell trials. The patients are seen at Seattle Cancer Care Alliance, the clinical care partner for Fred Hutch.

Fred Hutch co-authors of the paper are Kevin Hay, Laila-Aicha Hanafi, Shelly Heimfeld, Stanley R. Riddell and David G. Maloney. Other co-authors are Daniel Li, Juno Therapeutics; Sindhu Cherian, Xueyan Chen and Brent Wood, University of Washington; and Arletta Lozanski and John C. Byrd, The Ohio State University.

Funding for the project came from Juno Therapeutics, National Cancer Institute, National Institute of Diabetes and Digestive and Kidney Diseases, Life Science Discovery Fund, the Bezos family, and the University of British Columbia.

Turtle, Maloney and Riddell receive research funding from Juno Therapeutics and are named as inventors on one or more patents or patent applications related to this work. Riddell is a co-founder of Juno Therapeutics and has equity interest in Juno Therapeutics. Li is an employee of and has equity interests in Juno Therapeutics. Fred Hutch receives research funding from Juno Therapeutics.

Largest study of malaria gene function reveals many potential drug targets

The malaria parasite’s success is owed to the stripping down of its genome to the bare essential genes, scientists at the Wellcome Trust Sanger Institute and their collaborators have found. In the first ever large-scale study of malaria gene function, scientists analysed more than half of the genes in the parasite’s genome and found that two thirds of these genes were essential for survival — the largest proportion of essential genes found in any organism studied to date.

The results, published today (13 July) in Cell, identify many potential targets for new antimalarial drug development, which is an important finding for this poorly understood parasite where drug resistance is a significant problem.

Nearly half of the world’s population is at risk of malaria and more than 200 million people are infected each year. The disease caused the deaths of almost half a million people globally in 2015*.

The genetics of the parasite that causes malaria, Plasmodium, have been tricky to decipher. Plasmodium parasites are ancient organisms and around half their genes have no similar genes — homologs — in any other organism, making it difficult for scientists to find clues to their function. This study provides the first ever experimental evidence of function for most of the genes.

Scientists studied the genes in one species of malaria, Plasmodium berghei, which were expressed in a single blood stage of its complicated, multi-stage life cycle. In the study, scientists designed a new method to decipher the function of the malaria parasite’s genes. The team switched off, or knocked out, 2,578 genes — more than half of the genome — and gave each knockout a unique DNA barcode**.

The team then used next generation genome sequencing technology to count those barcodes, and hence measure the growth of each genetically modified malaria parasite. If the switched-off gene was not essential, the parasite numbers shot up, but if the knocked out gene was essential, the parasite disappeared.

Dr Oliver Billker, joint lead author from the Wellcome Trust Sanger Institute, said: “This work was made possible by a new method that enabled us to investigate more than 2,500 genes in a single study — more than the entire research community has studied over the past two decades. We believe that this method can be used to build a deep understanding of many unknown aspects of malaria biology, and radically speed up our understanding of gene function and prioritisation of drug targets.”

The team systematically showed that the malaria parasite can easily dispose of the genes which produce proteins that give away its presence to the host’s immune system. This poses problems for the development of malaria vaccines as the parasite can quickly alter its appearance to the human immune system, and as a result the parasite can build resistance to the vaccine.

Dr Julian Rayner, joint lead author from the Wellcome Trust Sanger Institute, said: “We knew from previous work that on its surface the malaria parasite has many dispensable parts. Our study found that below the surface the parasite is more of a Formula 1 race car than a clunky people carrier. The parasite is fine-tuned and retains the absolute essential genes needed for growth. This is both good and bad: the bad news is it can easily get rid of the genes behind the targets we are trying to design vaccines for, but the flip side is there are many more essential gene targets for new drugs than we previously thought.”

Dr Francisco Javier Gamo, Director of the Malaria Unit at GlaxoSmithKline, said: “This study of unprecedented scale has resulted in many more, unique drug targets for malaria. The Holy Grail would be to discover genes that are essential across all of the parasite lifecycle stages, and if we could target those with drugs it would leave malaria with nowhere to hide. The technology that the Sanger Institute has developed gives us the potential to ask those questions systematically for the first time.”

Genetically enhanced, cord-blood derived immune cells strike B-cell cancers

Immune cells with a general knack for recognizing and killing many types of infected or abnormal cells also can be engineered to hunt down cells with specific targets on them to treat cancer, researchers at The University of Texas MD Anderson Cancer Center report in the journal Leukemia.

The team’s preclinical research shows that natural killer cells derived from donated umbilical cords can be modified to seek and destroy some types of leukemia and lymphoma. Genetic engineering also boosts their persistence and embeds a suicide gene that allows the modified cells to be shut down if they cause a severe inflammatory response.

A first-in-human phase I/II clinical trial of these cord-blood-derived, chimeric antigen receptor-equipped natural killer cells opened at MD Anderson in June for patients with relapsed or resistant chronic lymphocytic leukemia (CLL), acute lymphocytic leukemia (ALL), or non-Hodgkin lymphoma. All are cancers of the B cells, another white blood cell involved in immune response.

“Natural killer cells are the immune system’s most potent killers, but they are short-lived and cancers manage to evade a patient’s own NK cells to progress,” said Katy Rezvani, M.D., Ph.D., professor of Stem Cell Transplantation and Cellular Therapy.

“Our cord-blood derived NK cells, genetically equipped with a receptor that focuses them on B-cell malignancies and with interleukin-15 to help them persist longer — potentially for months instead of two or three weeks — are designed to address these challenges,” Rezvani said.

Moon Shots Program funds project

The clinical trial is funded by MD Anderson’s Moon Shots Program™, designed to more rapidly develop life-saving advances based on scientific discoveries.

The chimeric antigen receptor (CAR), so-called because it’s added to the cells, targets CD19, a surface protein found on B cells.

In cell lines and mouse models of lymphoma and CLL, CD19-targeted NK cells killed cancer cells and extended survival of animals compared to simply giving NK cells alone. Addition of IL-15 to the CD19 receptor was crucial for the longer persistence and enhanced activity of the NK cells against tumor cells.

NK cells are a different breed of killer from their more famous immune system cousins, the T cells. Both are white blood cells, but T cells are highly specialized hunters that look for invaders or abnormal cells that bear a specific antigen target, kill them and then remember the antigen target forever.

Natural killers have an array of inhibitory and activating receptors that work together to allow them to detect a wider variety of infected, stressed or abnormal cells.

“By adding the CD19 CAR, we’re also turning them into guided missiles,” said Elizabeth Shpall, M.D., professor of Stem Cell Transplantation and Cell Therapy.

Using a viral vector, the researchers transduce NK cells taken from cord blood with the CD19 CAR, the IL-15 gene, and an inducible caspase-9-based suicide gene.

Cell line tests found the engineered NK cells to be more efficient killers of lymphoma and CLL cells, compared to unmodified NK cells, indicating the engineered cells’ killing was not related to non-specific natural killer cell cytotoxicity.

Another experiment showed the engineered cord blood NK cells killed CLL cells much more efficiently than NK cells taken from CLL patients and engineered, highlighting the need to transplant CAR-engineered NK cells from healthy cord blood rather than use a patient’s own cells.

Suicide gene to counter cytokine release syndrome

Mouse model lymphoma experiments using a single infusion of low dose NK cells resulted in prolongation of survival. At a higher, double dose, none of the mice treated with the CD19/IL-15 NK cells died of lymphoma, with half surviving for 100 days and beyond. All mice treated with other types of NK cells died by day 41.

A proportion of mice treated with the higher dose of engineered NK cells died of cytokine release syndrome, a severe inflammatory response that also occurs in people treated with CAR T cells.

To counteract this toxicity, the researchers incorporated a suicide gene (iC9) that can be activated to kill the NK cells by treatment with a small-molecule dimerizer. This combination worked to swiftly reduce the engineered NK cells in the mouse model.

Subsequent safety experiments were conducted in preparation for the clinical trial. Rezvani, the principal investigator of the clinical trial, says the protocol calls for vigilance for signs of cytokine release syndrome, treatment with steroids and tocilizumab for low-grade CRS with AP1903 added to activate the suicide gene for grade 3 or 4 CRS.

NK CARs available off the shelf

T cells modified with chimeric antigen receptors against CD19 have shown efficacy in clinical trials. In these therapies, a patient’s own T cells are modified, expanded, and given back to the patient, a process that takes weeks. Finding a matched donor for T cells would be a challenge, but would be necessary because unmatched T cells could attack the recipient’s normal tissue – graft vs. host disease.

Rezvani and Shpall have given patients cord-blood derived NK cells in a variety of clinical trials and found that they do not cause graft vs. host disease, therefore don’t have to be matched. NK cells can be an off-the-shelf product, prepared in advance with the necessary receptor and given promptly to patients.

“CAR NK cells are scalable in a way that CAR T cells are not,” Rezvani noted.

A strength of T cells is the development of memory cells that persist and repeatedly attack cells bearing the specific antigen that return. NK cells do not seem to have a memory function, but Rezvani says the experience of the longer-lived mice, which are now more than a year old, raises the possibility that a prolonged NK cell attack will suffice.

Shpall, Rezvani and colleagues are developing cord blood NK CARs for other targets in a variety of blood cancers and solid tumors.

MD Anderson and the researchers have intellectual property related to the engineered NK cells, which is being managed in accordance with the institution’s conflict-of-interest rules.

Shpall founded and directs MD Anderson’s Cord Blood Bank, originally established to provide umbilical cord blood stem cells for patients who need them but cannot get a precise donor match. Donated by mothers who deliver babies at seven Houston hospitals and two others from California and Michigan, the bank now has 26,000 cords stored. MD Anderson researchers pioneered the extraction and expansion of NK cells from umbilical cords.

Tumor-Targeting Drug Shows Potential for Treating Bone Cancer Patients

Preclinical study shows BMTP-11 targets high-risk osteosarcoma

The treatment of osteosarcoma, the most common tumor of bone, is challenging. A study led by The University of Texas MD Anderson Cancer Center found a drug known as bone metastasis-targeting peptidomimetic (BMTP-11) has potential as a new therapeutic strategy for this devastating illness.

Results from the preclinical study, which looked at BMTP-11 alone and in combination with the chemotherapy agent gemcitabine, were published in the July 11, 2017, online issue of Proceedings of the National Academy of Sciences.

Although osteosarcoma is a relatively rare cancer, it is a leading disease-related cause of death in children and young adults ages 10 to 20. However, over the last 25 years, the five-year survival rate has remained unchanged, and the treatment options for these patients are few. In addition, the side effects of available treatment options often are significant and cumulative, and may cause other health problems and damage to major organs.

“What’s novel about this treatment is that BMTP -11 targets the tumor and spares other organs,” said Valerae O. Lewis, M.D., chair of Orthopaedic Oncology at MD Anderson. “We believe this study lays the groundwork for a clinical trial for the treatment of osteosarcoma without the cumulative and mortal side effects seen with the current treatment options.”

The study results identified IL-11Rα as an osteosarcoma cell surface receptor that correlated with tumor progression and poor prognosis in osteosarcoma patients. The team, which included co-authors Renata Pasqualini, Ph.D., and Wadih Arap, M.D., Ph.D., both of whom worked on the study while at MD Anderson and are now professors at the University of New Mexico Health Sciences Center (UNMSC) School of Medicine, also illustrated that IL-11Rα and IL-11 are up-regulated in human metastatic osteosarcoma cell lines, and this correlated with the development of lung metastases in mouse models of the disease. The metastatic potential of the osteosarcoma cell lines could be modulated by targeting IL-11Rα expression. Death from respiratory failure linked to metastasis to the lungs remains a significant problem among osteosarcoma patients.

“We were able to document anti-tumor activity against osteosarcoma models,” said Pasqualini. “Given that a first-in-human trial of BMTP-11 has recently been reported, one would hope that this proof-of-concept study might lead to early translational clinical trials in human osteosarcoma as a logical next step in the context of an unmet medical oncology need.”

Arap added that “this work provides a preclinical foundation for the potential design and development of a second line combination therapy regimen composed of conventional chemotherapeutics plus the targeted candidate drug BMTP-11 for application in unfortunate patients with recalcitrant osteosarcoma.”

Blood Test for Early Detection of Pancreatic Cancer Headed to Clinic

A newly identified biomarker panel could pave the way to earlier detection and better treatment for pancreatic cancer, according to new research from the Perelman School of Medicine at University of Pennsylvania. Currently over 53,000 people in the United States are diagnosed with pancreatic cancer — the fourth leading cause of cancer death — every year. The blood biomarkers, detailed today in Science Translational Medicine, correctly detected pancreatic cancer in blood samples from patients at different stages of their disease.

The majority of pancreatic cancer patients are not diagnosed until an advanced stage, beyond the point at which their tumors can be surgically removed.

A team led by Ken Zaret, PhD, director of the Penn Institute for Regenerative Medicine and the Joseph Leidy Professor of Cell and Developmental Biology, and Gloria Petersen, PhD, from the Mayo Clinic, identified a pair of biomarkers that physicians could soon use to discover the disease earlier.

“Starting with our cell model that mimics human pancreatic cancer progression, we identified released proteins, then tested and validated a subset of these proteins as potential plasma biomarkers of this cancer,” Zaret said. The authors anticipate that health care providers will use the early-detection biomarkers to test for their presence and levels in blood from pancreatic cancer patients and blood drawn from individuals with a high risk of developing pancreatic cancer, including those who have a first-degree relative with pancreatic cancer, are genetically predisposed to the disease, or who had a sudden onset of diabetes after the age of 50.

“Early detection of cancer has had a critical influence on lessening the impact of many types of cancer, including breast, colon, and cervical cancer. A long standing concern has been that patients with pancreatic cancer are often not diagnosed until it is too late for the best chance at effective treatment,” said Robert Vonderheide, MD, DPhil, director of the Abramson Cancer Center (ACC) at the University of Pennsylvania. “Having a biomarker test for this disease could dramatically alter the outlook for these patients.”

The biomarker panel, enabled by discovery work of first author Jungsun Kim, PhD, a postdoctoral fellow in Zaret’s lab, builds on a first-of-its-kind human-cell model of pancreatic cancer progression the lab described in 2013. They used stem-cell technology to create a cell line from a patient with advanced pancreatic ductal adenocarcinoma. Genetically reprogramming late-stage human cancer cells to a stem-cell state enabled them to force the reprogrammed cells to progress to an early cancerous state, revealing secreted blood biomarkers of early-stage disease along the way.

The best candidate biomarker, plasma thrombospondin-2 (THBS2), was screened against 746 cancer and control plasma samples using an inexpensive, commercially available protein-detection assay. The team found that blood levels of THBS2, combined with levels of a known later-stage biomarker called CA19-9, was reliable at detecting the presence of pancreatic cancer in patients.

The team refined the assay with independent investigations of plasma samples from patients with different stages of cancer, from individuals with benign pancreatic disease, and from healthy controls, all obtained from Petersen, who directs the biospecimen resource program for pancreas research at the Mayo Clinic.

“Positive results for THBS2 or CA19-9 concentrations in the blood consistently and correctly identified all stages of the cancer,” Zaret said. “Notably, THBS2 concentrations combined with CA19-9 identified early stages better than any other known method.” The combination panel also improved the ability to distinguish cases of cancer from pancreatitis. The panel will next be validated in a set of samples from pancreatic cancer patients who provided a research blood sample prior to their diagnosis.

Breathing in a New Gene Therapy to Treat Pulmonary Hypertension

Mount Sinai has partnered with Theragene Pharmaceuticals, Inc. to advance a novel airway-delivered gene therapy for treating pulmonary hypertension (PH), a form of high blood pressure in blood vessels in the lungs that is linked to heart failure. If the therapy succeeds in human clinical trials, it will provide patients for the first time with a way to reverse the damage caused by PH.

This gene therapy technique comes from the research of Roger J. Hajjar, MD, Professor of Medicine and Director of the Cardiovascular Research Center at the Icahn School of Medicine at Mount Sinai, and has been proven effective in rodent and pig animal models. PH is a deadly disease that disproportionately affects young adults and women; 58 percent of cases are found in young adults and 72 percent are women. There is currently no effective cure for PH, and about 50 percent of people who are diagnosed will die from the disease within five years.

PH is a rare (15-50 cases per million people), rapidly progressing disease that occurs when blood pressure is too high in vessels leading from the heart to the lungs. The high pressure is caused by abnormal remodeling of the lung blood vessels, characterized by a proliferation of smooth muscle cells and a thickening and narrowing of these vessels, and can lead to failure of the right ventricle of the heart and premature death. Abnormalities in calcium cycling within the vascular cells play a key role in the pathophysiology of pulmonary hypertension, along with deficiencies in the sarcoplasmic reticulum calcium ATPase pump (SERCA2a) protein which regulates intracellular calcium within these vascular cells and prevents them from proliferating within the vessel wall. Downregulation of SERCA2a leads to the proliferative remodeling of the vasculature. This gene therapy, delivered via an inhaled aerosolized spray, aims to increase the expression of SERCA2a protein, and has been shown in rodents and pigs to improve heart and lung function, as well as reduce and even reverse cellular changes caused by PH.

Targeting ‘broken’ metabolism in immune cells reduces inflammatory disease

The team, led by researchers at Imperial College London, Queen Mary University of London and Ergon Pharmaceuticals, believes the approach could offer new hope in the treatment of inflammatory conditions like arthritis, autoimmune diseases and sepsis.

In a study published this week in the journal Nature Communications, they explain how blocking a single enzyme enabled them to reprogram macrophages – the immune cells which are activated in inflammatory conditions – to calm their activity and reduce inflammation in rats and mice with human-like disease.

At the heart of the research is the Krebs cycle, a complex loop of reactions which cells use to feed on sugar and generate molecules of ATP, the universal energy currency for cells.

In recent years, research has shown that the usual pathway is interrupted in immune cells such as macrophages, leading to a broken Krebs cycle.

“In immune cells that have to fight invaders, the metabolism is diverted from its usual cycle to make compounds that fight microbes,” explained Dr Jacques Behmoaras, from the Department of Medicine at Imperial, who led the research.

Dr Behmoaras added: “What we have found is that there’s an enzyme involved in this diversion of the usual cycle, which make immune cells produce these bacteria-killing compounds. If you block that enzyme, you block that specific branch of their metabolism, and make the cells cause less damage during inflammation.”

Using human macrophages, the researchers found that an enzyme called BCAT1 was pivotal in reprogramming macrophages. When the cells were activated – by exposing them to molecules found on the surface of bacteria – BCAT1 interfered with their usual metabolic pathways, and regulated another enzyme, responsible for producing bacteria-killing chemicals.

They used an experimental compound called ERG240, developed by Ergon Pharmaceuticals, a small biotech company based in the US. ERG240 resembles the amino acid leucine, one of the building blocks of proteins, which is linked together by BCAT1. By flooding the cells with ERG240 they were able to jam up BCAT1 and block its action, so stopping the metabolism being diverted and ‘fixing’ the broken Krebs cycle. What’s more, the compound was shown to work in animal models of inflammation, without toxic side effects.

The team found that when ERG240 was given to mice with symptoms of rheumatoid arthritis, it reduced the inflammation in their joints by more than half while protecting the integrity of their joints. Similarly, in a rat model of severe kidney inflammation, they found that ERG240 improved kidney function by reducing the number of macrophages flooding into the affected tissue to cause inflammation.

Dr Behmoaras states that although the research is still at an early stage, there is potential for treating inflammatory conditions in patients by targeting the metabolic activity in immune cells. The team believes that BCAT1 works together with other key enzymes of the Krebs cycle, which could themselves provide targets for therapy.

However, one of the key challenges in developing a therapy would be in finding the balancing point: calming the immune cells enough such that they reduce inflammation, but enabling them to react to microbial invaders.

“I think this ability to regulate metabolism in cells could have an effect on many human diseases,” said Dr Behmoaras. “Manipulating cell activity in inflammatory diseases where macrophages have a role, could have important therapeutic benefits.

“Our next step is to understand how other enzymes in the cycle are involved, to see if there is any possibility to block them and have similar effects. Understanding the complex metabolic circuits of these immune cells is a huge task. We will need to tackle this before we can manipulate cell activity and influence disease.

“This is a growing field of research with exciting discoveries ahead.”

Personal neoantigen vaccine prompts strong anti-tumor response in patients, study shows

A personal cancer treatment vaccine that targets distinctive “neoantigens” on tumor cells has been shown to stimulate a potent, safe, and highly specific immune anti-tumor response in melanoma patients, report scientists from Dana-Farber Cancer Institute and the Broad Institute of MIT and Harvard.

The study, published online by Nature “provides proof-of-principle that a personal vaccine tailored to a patient’s tumor can be produced and generates highly specific responses to that patient’s tumor after vaccination,” said the researchers, led by Catherine J. Wu, MD, senior author of the report. She is a researcher at Dana-Farber, the Broad Institute, and Harvard Medical School.

The scientists said that while most therapies are based on the on-size-fits-all model of medicine, “we’ve long recognized in cancer that every patient’s tumor is different. With recent advances in technology, it’s now becoming possible to create a therapy that’s suited to target an individual’s tumor.”

The researchers say the results warrant further development of neoantigen vaccines, both alone and in combination with other immunotherapy weapons such as checkpoint inhibitors. The vaccine, known as NeoVax, prompted strong activity by the patients’ immune systems while causing negligible side effects.

First authors of the report are Patrick A. Ott, MD, PhD, and Zhuting Hu, PhD, of Dana-Farber. Other senior authors include Nir Hacohen, PhD, of the Broad Institute and Massachusetts General Hospital, Edward Fritsch, PhD, formerly of Dana-Farber and now at Neon Therapeutics in Cambridge, Mass, and Eric Lander, PhD, of the Broad Institute.

Antigens are molecules that are displayed on the surface of cells and stimulate the immune system. Neoantigens are molecules on cell’s surfaces that are produced by DNA mutations that are present in cancer cells but not in normal cells, making neoantigens ideal targets for immune therapy against cancer, say the scientists. The vaccines used in the phase I trial contained up to 20 neoantigens, derived from an individual patient’s tumor. The vaccines were administered to patients to train their immune system to recognize these neoantigens, with the goal of stimulating the immune system to destroy the cancer cells that display them.

While other immunotherapies, such as checkpoint inhibitor drugs, also trigger immune responses against cancer neoantigens, they are not designed to be specific. They can also induce responses against normal tissue antigens, leading the immune system to attack normal tissues and cause toxicity in a subset of patients. The researchers found that the personal vaccine induced a focused T cell response against several tumor neoantigens, beyond what is normally seen in response to existing immunotherapies.

The vaccine was administered to six patients with melanoma whose tumors had been removed by surgery and who were considered at high risk for recurrence. The vaccinations were started at a median of 18 weeks after surgery. At a median of 25 months after vaccination, four of the six patients showed no evidence of cancer recurrence. In the other two patients, whose cancer had spread to their lungs, the disease recurred after vaccination. At that point, they began treatment with the drug pembrolizumab, which inhibits the PD-1 immune checkpoint. Both patients had complete resolution of their tumors and remain free of disease according to imaging scans.

The study results suggest, that a personalized neoantigen vaccine can potentially overcome two major hurdles in cancer therapy.

One is the heterogeneity of tumors – the fact that they are made up of cells with a variety of different traits, which often allows cancers to evade drugs targeted to malignant cells having a single genetic abnormality. The vaccine, because it contains many different neoantigens from the tumor, targets multiple genetic types of tumor cells. Wu added that in this respect, the response generated by a neoantigen vaccine is similar to the new wave of combination therapies, which are showing more promise in treating cancers that typically develop resistance to single drugs. “We are leveraging the immune system’s natural ability to detect and attack many target antigens, as it does every time we get an infection,” she said.

A second hurdle in cancer is to generate an immune response sharply focused on cancer cells while avoiding normal cells and tissues. This aim was achieved by the vaccine, which appeared to have few “off-target” effects, causing only flu-like symptoms, fatigue, rashes, and irritation at the site of the vaccine injection, according to the report.

Despite decades of attempts to develop effective cancer treatment vaccines, they have mostly failed at producing potent antitumor immune responses. The study authors say that is because these vaccines have generally been made with tumor antigens that are too similar to antigens on normal cells: as a result, the body generates a weaker immune response to avoid harming normal cells, a process called immune tolerance. By contrast, the neoantigen vaccine is custom-made for each patient using antigens produced by mutations unique to the patient’s cancer and only present on cancer cells, thus bypassing the nature immune tolerance process.

To create the vaccine, samples of a patient’s tumor and normal DNA from the patient’s blood underwent whole-exome sequencing to reveal mutations present only in the tumor’s genetic program. Because some mutations are present in the DNA but the gene is not made into RNA and protein, the researchers used RNA sequencing to identify mutations that caused the production of a mutated RNA, which is then normally translated into a protein.

Since T cells can only recognize neoantigens that are “presented” to them by HLA molecules of the immune system, a key step in making the vaccine is using computer algorithms to predict which neoantigen peptides will bind strongly to the HLA molecules for recognition by T cells. Algorithms, such as NetMHC, have been developed in recent years, making it feasible to select HLA-binding neoantigen peptides for the vaccine. Applying this tool to the six patients’ tumor samples yielded dozens of unique neoantigens for each patient’s personal vaccine.

Finally, the selected neoantigen peptides were synthesized and mixed with an adjuvant – a biochemical substance that helps to jump-start the immune response. The vaccine was then injected under the skin of the patient, with five priming doses followed by two booster doses of the vaccine.

The vaccine was aimed at generating responses to the neoantigens from T cells of two kinds – CD8+ killer cells and CD4+ helper cells. When the team monitored the vaccine’s effects on the immune system in each patient, they found that both T cell types had indeed been activated by the vaccine and could recognize the neoantigens bound to HLA molecules. Most importantly, many of the T cells were able to recognize the tumor cells directly, demonstrating that the vaccine had triggered a tumor-specific immune response that could target the patient’s tumor.

“Future neoantigen vaccine trials will recruit more patients with advanced disease to test the efficacy of the vaccine, take advantage of improved methods for predicting antigen presentation to boost the number of effective neoantigens and test for synergy with checkpoint blockade and other immunotherapeutics,” the scientists said. “If successful in subsequent trials, a personal vaccine has the potential to be applied to any cancer that harbors a sufficient numbers of neoantigens for vaccination.”

FDA Halts Three Multiple Myeloma Studies Evaluating Merck’s KEYTRUDA®

Merck known as MSD outside the United States and Canada, today announced that the U.S. Food and Drug Administration (FDA) has placed a clinical hold on KEYNOTE-183, KEYNOTE-185 and KEYNOTE-023, three combination studies of KEYTRUDA® (pembrolizumab), the company’s anti-PD-1 therapy, in the blood cancer multiple myeloma.

This decision follows a review of data by the Data Monitoring Committee in which more deaths were observed in the KEYTRUDA arms of KEYNOTE-183 and KEYNOTE-185 and which led to the pause in new patient enrollment, as announced on June 12, 2017. The FDA has determined that the data available at the present time indicate that the risks of KEYTRUDA plus pomalidomide or lenalidomide outweigh any potential benefit for patients with multiple myeloma. All patients enrolled in KEYNOTE-183 and KEYNOTE-185 and those in the KEYTRUDA/lenalidomide/dexamethasone cohort in KEYNOTE-023 will discontinue investigational treatment with KEYTRUDA.

This clinical hold does not apply to other studies with KEYTRUDA.

The following studies have been placed on full clinical hold:

  • KEYNOTE-183: “A Phase III study of Pomalidomide and low-dose Dexamethasone with or without Pembrolizumab (MK3475) in refractory or relapsed and refractory Multiple Myeloma (KEYNOTE-183).”
  • KEYNOTE-185: “A Phase III study of Lenalidomide and low-dose Dexamethasone with or without Pembrolizumab (MK3475) in newly diagnosed and treatment naïve Multiple Myeloma (KEYNOTE-185).”

The following study has been placed on partial clinical hold:

  • KEYNOTE-023 Cohort 1: “A Phase I Multi-Cohort Trial of Pembrolizumab (MK-3475) in Combination with Backbone Treatments for Subjects with Multiple Myeloma (KEYNOTE 023).” Cohort 1 of KEYNOTE-023 evaluated KEYTRUDA (pembrolizumab) in combination with lenalidomide and dexamethasone in patients who received prior anti-multiple myeloma treatment with an immunomodulatory (IMiD) treatment (lenalidomide, pomalidomide or thalidomide).

“Patient safety is Merck’s primary concern, and we are grateful to the study investigators and patients involved in these studies for their commitment to this important research,” said Dr. Roger M. Perlmutter, president, Merck Research Laboratories. “Merck’s development program for KEYTRUDA, spanning more than 30 different tumor types, has one priority: helping patients suffering from cancer.”

For more information about Merck’s oncology clinical trials, visit www.merck.com/clinicaltrials.

First Large-Scale Genomic Analysis of Key Acute Leukemia Will Likely Yield New Therapies

A consortium including St. Jude Children’s Research Hospital and the Children’s Oncology Group has performed an unprecedented genomic sequencing analysis of hundreds of patients with T-lineage acute lymphoblastic leukemia (T-ALL). The results provide a detailed genomic landscape that will inform treatment strategies and aid efforts to develop drugs to target newly discovered mutations.

The data will also enable researchers to engineer better mouse models to probe the leukemia’s aberrant biological machinery.

The project’s 39 researchers were led by Charles Mullighan, M.D., MBBS, a member of the St. Jude Department of Pathology, with co-corresponding authors Jinghui Zhang, Ph.D., chair of the St. Jude Department of Computational Biology and Stephen Hunger, M.D., of the Children’s Hospital of Philadelphia. The research was selected for advance online publication today in the journal Nature Genetics.

“This first comprehensive and systematic analysis in a large group of patients revealed many new mutations that are biologically significant as well as new drug targets that could be clinically important,” Mullighan said. “Leukemias typically arise from multiple genetic changes that work together. Most previous studies have not had the breadth of genomic data in enough patients to identify the constellations of mutations and recognize their associations.”

T-ALL is a form of leukemia in which the immune system’s T cells acquire multiple mutations that freeze the cells in an immature stage, causing them to accumulate in the body. ALL is the most common type of childhood cancer, affecting about 3,000 children nationwide each year. T-ALL constitutes about 15 percent of those cases. While about 90 percent of children with ALL can be cured, many still relapse and require additional treatment.

The multi-institutional effort involved sequencing the genomes of 264 children and young adults with T-ALL—the largest such group ever analyzed. The study involved sophisticated analysis of multiple types of genomic data, led by Yu Liu, Ph.D., a postdoctoral fellow in Zhang’s Computational Biology laboratory and first author of the study. Their analyses identified 106 driver genes—those whose mutations trigger the malfunctions that block normal T cell development and give rise to cancer. Half of those mutated genes had not been previously identified in childhood T-ALL.

The study enabled the researchers to compare the frequencies of mutations among patients whose cancerous cells were sequenced at the same detailed level, Mullighan said. Also important, he said, was that all the patients had uniform treatment, which enabled the researchers to draw meaningful associations between the genetics of their cancer and the response to different treatments. Such associations will enable better diagnosis and treatment of T-ALL with existing drugs.

Researchers analyzed the cancerous T cells as well as those that treatments had rendered non-cancerous. Comparing the two populations of cells could reveal valuable clues about why specific treatments were successful in thwarting particular cancer-causing mutations.

The findings revealed significant unexpected findings. “We went into this study knowing that we didn’t know the full genomic landscape of T-ALL,” Hunger said. “But we were surprised that over half of the new targets and mutations were previously unrecognized. It was particularly unexpected and very striking that some mutations were exclusively found in some subtypes of T-ALL, but not others.”

Cancers are driven by mutations in genes that are the blueprint for protein enzymes in signaling pathways in cells—the biological equivalent of circuits in a computer. While a cancer may arise from an initial founding mutation, that mutation triggers a cascade of other mutations that help drive the cancer.

The new genomic analysis confirmed that T-ALL was driven by mutations in known signaling pathways, including JAK–STAT, Ras and PTEN–PI3K.

However, the new analysis identified many more genetic mutations in those known pathways. The findings offered more targets for drugs to shut down the aberrant cells. “So the frequency of the patients that are potentially amenable to these targeted approaches is higher than we appreciated before,” Mullighan said.

The researchers also found cases in which the same T-ALL subtype had mutations in different pathways triggered by the same cancer-causing founding mutation. “We believe this finding suggests we can target such subtypes with an inhibitor drug for one of the pathways, and it’s likely to be effective,” Mullighan said.

The multitude of new mutations uncovered in the new study will also enable researchers to use genetic engineering to create mouse models that more accurately reflect human cancer, he said. Such models are invaluable for understanding the biological machinery of T-ALL, as well as testing new drug strategies. “We now have a launching pad, if you will, to design mouse models that include multiple genetic mutations to more faithfully reflect the leukemias we see in humans,” Mullighan said.

The research also offers a broader lesson for genomic studies of cancers, Zhang said. “Our study is further evidence that if you systematically study a large enough population with careful, detailed genomic analysis, you will discover new mutational patterns of collaboration or exclusion across multiple genes unique to each T-ALL subtype,” she said.

The study was a collaboration between the St. Jude Children’s Research Hospital – Washington University Pediatric Cancer Genome Project, the Children’s Oncology Group (COG) and the National Cancer Institute’s Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. COG is a federally supported clinical trials group focused exclusively on childhood cancer. TARGET uses genomic analysis of COG samples to identify therapeutic targets and spur development of more effective treatment for childhood cancer.

HPV Testing Leads to Earlier Detection and Treatment of Cervical Precancer

Women who receive human papillomavirus (HPV) testing, in addition to a pap smear, receive a faster, more complete diagnosis of possible cervical precancer, according to a study of over 450,000 women by Queen Mary University of London (QMUL) and the University of New Mexico (UNM) Comprehensive Cancer Center.

HPV is a virus that can cause cervical, vaginal, penile and anal cancers. More than 520,000 cases of cervical cancer are diagnosed worldwide each year, causing around 266,000 deaths. A common screening procedure for cervical cancer is the Pap smear, which tests for the presence of precancerous or cancerous cells on the cervix.

The study, published in JAMA Oncology, used data from the New Mexico HPV Pap Registry in the United States. It is the first comprehensive evaluation of HPV testing on the long-term outcomes of women who had received a borderline abnormal Pap test result.

A total of 457,317 women were included in the study. Of these, 20,677 women (4.5 percent) received a borderline abnormal result through a Pap smear and were followed in the study for five years. Some of the women with borderline abnormal Pap smear results had an HPV test.

HPV testing led to a 15.8 percent overall increase in the detection of cervical precancers and time to detection was much shorter (a median of 103 days versus 393 days).

Virtually all cervical pre-cancers were detected in women who tested positive for HPV, suggesting HPV testing to be a good additional screening method after the Pap smear. Colposcopy, which is a medical examination of the cervix, could then be focused on women who would need it most: those with a positive HPV test.

At the same time, however, HPV testing of women resulted in 56 percent more biopsies and a 20 percent increase in surgical treatment procedures performed. Most of the additional biopsies were for low grade lesions which could have regressed, indicating some overtreatment due to HPV testing.

Professor Jack Cuzick from QMUL said: “This study shows that knowing a woman’s HPV status can help determine her likelihood of needing additional procedures, and prioritise immediate treatment and medical resources to the women who need them most.”

Professor Cosette Wheeler from the UNM Comprehensive Cancer Center said: “The benefits of HPV testing outweigh the harms observed but it’s important to understand and quantify the harms as well.”

The authors warn that, as this was an observational study, the use of HPV testing was not randomised. So, it is also possible that there could be socioeconomic or other relevant differences among health care facilities that have not been measured.

Study Shows How an Opportunistic Microbe Kills Cancer Cells and Identifies Specialized Vesicles Responsible for Cell Reproduction

New study results show for the first time how dying cells ensure that they will be replaced, and suggests an ingenious, related new approach to shrinking cancerous tumors. A research team from Rush University Medical Center will publish a new paper this week in the journal Developmental Cell that describes two groundbreaking discoveries.

“I believe this discovery is going to have important ramifications on cancer biology and cancer drug development, and on the treatment of other diseases such as diabetic foot ulcers,” says Sasha Shafikhani, PhD, associate professor of Hematology, Oncology and Cell Therapy at Rush Medical College, who headed up the study.

The team made its two-pronged discovery while investigating how an opportunistic microbe kills cancer cells. For years, Shafikhani’s lab has been studying Pseudomonas aeruginosa, a bacterium that can be lethal, but only to people who are already wounded or sick. This pathogenic bacterium secretes several toxins that allow it to cause infection. One such toxins, ExoT, inhibits cell division and can severely impede wound healing, but it’s also known to kill cancer cells.

The researchers were trying to figure out ExoT’s lethal mechanisms against cancer when they unlocked, almost by accident, a mystery researchers have been trying to solve for years, Shafikhani says. For at least 20 years, medical researchers have wondered how cells, before they die in the normal process of apoptosis, manage to alert their neighbors of the need to replace them and compensate for their demise, so to ensure the organism’s survival. While shining a light on the lethal habits of Pseudomonas aeruginosa, Shafikhani’s team discovered what actually happens in that “compensatory proliferation signaling” (CPS) process.

For the first time, the investigators saw — and have shown in amazing videos they produced — that during CPS, dying cells release “microvesicles” containing the CrkI protein, which travel to neighboring cells and cause them, upon contact, to create new cells to replace the ones that are dying.

Apoptosis is part of life. “In the course of normal tissue turnover in humans, about one million cells die every second, through a highly-regulated process of apoptotic programmed cell death (PCD),” the new paper states. Apoptosis is not the only type of cell death, and not all cells dying of apoptosis are capable of CPS.

Not only that, but Shafikhani and his colleagues have demonstrated that if they knocked out the CrkI protein during CPS, either genetically or with the ExoT toxin, they could stop cell compensatory proliferation cold. That’s a trick P. aeruginosa uses to take advantage of damaged tissues, but it has exciting possibilities for disease treatment as well.

Apoptosis is of particular interest to cancer researchers because majority of the current cancer drugs kill cancer cells by apoptosis.

However, CPS can dog apoptosis in cancer treatment. Yes, treated cancer cells can be induced to die, but before they do, they call on nearby cancer cells to replace them, so the drug loses its effectiveness and the tumor persists. But if the communication between the dying cancer cells and neighboring cancer cells is blocked, Shafikhani says, the hope is that the treated cancer cells would not be replaced when they die, and hopefully the tumor would disappear.

“If it’s possible to uncouple CPS from apoptosis, we can develop new drugs that would improve the effectiveness of treatments already in use,” Shafikhani says.

In cancer cells, the CPS process and communication would need to be interrupted to prevent the development of new cancer cells; but in other conditions, the CPS process could be enhanced to accelerate the healing process. One of the possible long-term benefits of the discoveries set out in the new Developmental Cell article could be to use of these vesicles to encourage cell proliferation — in diabetic wounds where healing is not going well because tissue cells are dysfunctional and have reduced ability to regenerate, for example, Shafikhani says.

All the researchers on the new study were from Rush University Medical Center.

Pre-Clinical Study Suggests Parkinson’s Could Start in Gut Endocrine Cells

Recent research on Parkinson’s disease has focused on the gut-brain connection, examining patients’ gut bacteria, and even how severing the vagus nerve connecting the stomach and brain might protect some people from the debilitating disease.

But scientists understand little about what’s happening in the gut — the ingestion of environmental toxins or germs, perhaps — that leads to brain damage and the hallmarks of Parkinson’s such as tremors, stiffness and trouble walking.

Duke University researchers have identified a potential new mechanism in both mice and human endocrine cells that populate the small intestines. Inside these cells is a protein called alpha-synuclein, which is known to go awry and lead to damaging clumps in the brains of Parkinson’s patients, as well as those with Alzheimer’s disease.

According to findings published June 15 in the journal JCI Insight, Duke researchers and collaborators from the University of California, San Francisco, hypothesize that an agent in the gut might interfere with alpha-synuclein in gut endocrine cells, deforming the protein. The deformed or misfolded protein might then spread via the nervous system to the brain as a prion, or infectious protein, in similar fashion to mad cow disease.

“There is abundant evidence that misfolded alpha-synuclein is found in the nerves of the gut before it appears in the brain, but exactly where this misfolding occurs is unknown,” said gastroenterologist Rodger Liddle, M.D., senior author of the paper and professor of medicine at Duke. “This is another piece of evidence that supports the hypothesis that Parkinson’s arises in the gut.”

Alpha-synuclein is the subject of much ongoing research on Parkinson’s, as it’s the main component of Lewy bodies, or toxic protein deposits that take up residence in brain cells, killing them from the inside. The clumps form when alpha-synuclein develops a kink in its normally spiral structure, making it ‘sticky,’ and prone to aggregating, Liddle said.

But how would a protein go from traveling through the inner-most ‘tube’ of the intestine, where there are no nerve cells, into the nervous system? That’s a question Liddle and colleagues sought to answer in a 2015 manuscript published in the Journal of Clinical Investigation. Although the main function of gut endocrine cells is to regulate digestion, the Duke researchers found these cells also have nerve-like properties.

Rather than using hormones to communicate indirectly with the nervous system, these gut endocrine cells physically connect to nerves, providing a pathway to communicate with the brain, Liddle said. The researchers demonstrated this in a stunning time-lapse video (2015, Journal of Clinical Investigation) in which a gut endocrine cell is placed under the microscope near a neuron. In just a few hours, the endocrine cell moves toward the neuron and fibers appear between them as they establish communication.

Liddle and other scientists were astonished at the video, he said, because the endocrine cells — which are not nerves — were behaving like them. This suggests they are able to communicate directly with the nervous system and brain.

With the new finding of alpha-synuclein in endocrine cells, Liddle and colleagues now have a working explanation of how malformed proteins can spread from the inside of the intestines to the nervous system, using a non-nerve cell that acts like a nerve.

Liddle and colleagues plan to gather and examine the gut endocrine cells from people with Parkinson’s to see if they contain misfolded or otherwise abnormal alpha-synuclein. New clues about this protein could help scientists develop a biomarker that could diagnose Parkinson’s disease earlier, Liddle said.

New leads on alpha-synuclein could also aid the development of therapies targeting the protein. Scientists have been investigating treatments that could prevent alpha-synuclein from becoming malformed, but much of the research is still in its early stages, Liddle said.

“Unfortunately, there aren’t great treatments for Parkinson’s disease right now,” he said. “It’s conceivable down the road that there could be ways to prevent alpha-synuclein misfolding, if you can make the diagnosis early.”

In addition to Liddle, study authors include Rashmi Chandra of Duke, Annie Hiniker and Yien-Ming Kuo of the University of California, San Francisco (UCSF), and Robert L. Nussbaum of UCSF and the Invitae Corporation.

Altered virus may expand patient recruitment in human gene therapy trials

For many patients, participating in gene therapy clinical trials isn’t an option because their immune system recognizes and fights the helpful virus used for treatment. Now, University of Florida Health and University of North Carolina researchers have found a solution that may allow it to evade the body’s normal immune response.

The discovery, published May 29 in the Proceedings of the National Academy of Sciences, is a crucial step in averting the immune response that prevents many people from taking part in clinical trials for various disorders, said Mavis Agbandje-McKenna, Ph.D., a professor in the University of Florida College of Medicine department of biochemistry and molecular biology and director of the Center for Structural Biology.

During gene therapy, engineered viruses are used to deliver new genes to a patient’s cells. While the recombinant adeno-associated virus, or AAV, is effective at delivering its genetic cargo, prior natural exposure to AAV results in antibodies in some people. As many as 70 percent of patients have pre-existing immunity that makes them ineligible for gene therapy clinical trials, Agbandje-McKenna said.

The findings provide a road map for designing virus strains that can evade neutralizing antibodies, said Aravind Asokan, Ph.D., an associate professor in the department of genetics at the University of North Carolina, who led the study. At UF Health, the structural “footprints” where pre-existing antibodies interact with the virus were identified using cryo-electron microscope resources provided by the UF College of Medicine and the UF Office of Research’s Division of Sponsored Programs. The UNC researchers then evolved new viral protein shells. Using serum from mice, rhesus monkeys and humans, the researchers showed that the redesigned virus can slip past the immune system.

“This is the blueprint for producing AAV strains that could help more patients become eligible for human gene therapy. Now we know how to do it,” Agbandje-McKenna said.

While the findings prove that one variation of AAV can be evolved, further study in preclinical models is needed before the approach can be tested in humans. Next, the immune profile of one particularly promising virus variant will need to be evaluated in a larger number of human serum samples, and dose-finding studies are needed in certain animal models. Researchers may also need to study whether the same virus-manipulating technique can be used in a broader range of gene therapy viruses, Agbandje-McKenna said.

Although human gene therapy remains an emerging field and has yet to reach patients on a wide scale, researchers elsewhere have used AAV therapy to successfully treat hemophilia, a blood-clotting disorder, in a small trial. It has also been or is now being studied as a way to treat hereditary blindness, certain immune deficiencies, neurological and metabolic disorders, and certain cancers.

The latest findings are the result of more than 10 years of studying the interactions between viruses and antibodies and a long-standing collaboration with Asokan, who heads the synthetic virology group at the UNC Gene Therapy Center, according to Agbandje-McKenna.