A vaccine that can prevent the recurrence and metastasis of cancer would save countless lives. In the past century, vaccines have virtually eradicated life threatening diseases including polio and tuberculosis. Medical science may soon be at the point of delivering a cancer vaccine.
Scientists at TapImmune are working closely with leading institutions and a big pharma collaborator including the Mayo Clinic, Memorial Sloan Kettering Cancer Center, the U.S. Department of Defense, and AstraZeneca, to bring such a cancer vaccine to market.
TapImmune’s lead cancer vaccine candidate, TPIV 200 is slated for four Phase II trials this year. Outstanding Phase I results from previous studies conducted at the Mayo Clinic are the impetus for Phase II trials in ovarian and breast cancer.
The Bio Connection recently spoke with TapImmune CEO Dr. Glynn Wilson about TPIV 200.
Q: Tell us about TPIV 200 and what makes it a vaccine, rather than a drug or a treatment?
TPIV 200 works much like vaccines that target other disease such as polio and tuberculosis because it stimulates the body’s cellular immune system to recognize and fight the disease. In this case, TPIV 200 targets cancer cells and in particular, it targets metastatic cancer, which is the biggest threat to survival. TPIV 200 broadly stimulates T-cells to recognize, remember, and attack specific targets (antigens) on tumor cells throughout the body.
TPIV 200 is also an off-the-shelf product, like most other vaccines today. It has been formulated and manufactured as a lyophilized (frozen) product with a long shelf life that can be administered via injection, without having to customize it for a specific person’s cancer cells.
Our clinical trials are designed to test TPIV 200’s efficacy in preventing cancer from recurring in people who have already been diagnosed with, and treated for, cancer, thus serving as a vaccine against cancer recurrence.
Q: Would TPIV 200 only be used in people who have already had cancer? What about people using it in a preventative way?
Since a majority of cancer deaths are caused by cancer recurrence and metastasis, not the original tumor, we see this as the area of greatest need. Indeed, in our target indications, ovarian and triple negative breast cancer, patients are at a high risk of cancer recurrence following standard treatments. That’s why we are evaluating the efficacy of TPIV 200 in preventing or delaying recurrence and metastasis.
We certainly see the possibility of developing a prophylactic, or preventative vaccine, for people who have not had cancer, but to do this you will normally need to demonstrate efficacy in a therapeutic setting. There is growing evidence, in preclinical studies, that a preventive vaccine may be viable. We are currently exploring additional studies in this area. A prophylactic cancer vaccine may potentially be developed based on either the TPIV 200 or TPIV 110 platforms. Or, our own in-house developed PolyStart platform also shows great promise for this.
Q: For a company your size, conducting four simultaneous Phase II trials is really impressive. How are you managing this strategy and why four at the same time?
Two of our upcoming Phase II trials are being conducted and financed in collaboration with world-class organizations. These reduce our clinical development costs significantly and they bring on board some of the top minds in immuno-oncology to work on TPIV 200.
With a $13.3 million grant, the U.S. Department of Defense is fully funding a double-blinded, placebo controlled Phase II study of TPIV 200 in 280 patients with triple negative breast cancer to be conducted at the Mayor Clinic in Jacksonville, Florida.
TapImmune is also collaborating with AstraZeneca on a Phase II trial in 40 patients with platinum resistant ovarian cancer, for a combination therapy of TPIV 200 with AstraZeneca’s anti-PD-L1 checkpoint inhibitor, durvalumab (MEDI4736). This study has begun enrollment and is being conducted at the Memorial Sloan Kettering Cancer Center in New York.
Two other Phase II studies are being funded and conducted by us. We recently dosed the first patient in our Phase II trial of TPIV 200 in triple negative breast cancer. This study, which will enroll 80 patients, is being conducted and funded by TapImmune. Later this year, we plan to commence another company conducted and funded Phase II trial in platinum sensitive ovarian cancer patients. Because we are conducting and funding these trials ourselves, we have greater control over the timing and pace of the trial. This is very helpful in terms of seeing data in the relative near term, and advancing our development timeline.
Our strategy is to move TPIV 200 along on multiple fronts via both our own company sponsored trials and by collaborating with others, to reduce our development costs.
Q: Why do you think AstraZeneca, which can partner with just about anyone chose TapImmune’s TPIV 200? Do you see this collaboration with AstraZeneca expanding into something more?
The collaboration started with the Principal Investigator at Memorial Sloan Kettering, Dr. Jason Konner, who saw the potential of combining a leading checkpoint inhibitor with a T-cell vaccine in ovarian cancer patients. Clinicians at AstraZeneca then reviewed the technical and clinical data on TPIV 200, resulting in the current collaboration. They are a big believer in testing combination therapies and are conducting over a dozen clinical trials of their checkpoint inhibitor durvalumab in combination with other compounds.
It’s premature to say anything about a deepening relationship AstraZeneca at this point, but we are very pleased they saw enough promise in TPIV 200 to conduct a collaborative trial with us. If favorable data emerges from the Phase II trial, that may be the impetus for us to discuss an expanded relationship with AstraZeneca.
Q: Can you tell us more about your other cancer vaccine, TPIV 110?
We plan to initiate a Phase II clinical trial of TPIV 110 at the start of 2017. TPIV 110 is a proprietary HER2neu vaccine technology. The HER2neu antigen is a well-established therapeutic target and plays a role in breast, ovarian and colorectal cancer. Each of these is a potential indication for this vaccine. Like TPIV 200, TPIV 110 was originally developed at the Mayo Clinic and TapImmune has a worldwide exclusive license on these technologies. The Mayo Clinic successfully concluded a Phase I trial in HER2neu breast cancer patients that evaluated TPIV 100, a precursor to TPIV 110 which has 4 Class II antigens. TPIV 100 was found to be safe, well-tolerated, and provided a robust immune response across a broad patient population. 19 out of 20 patients showed a robust T-cell response to two antigens and 15 out of 20 patients showed a response to all four antigens. TPIV 110 has been formulated with an additional 5th antigen, which is a Class I antigen, expected to make it more potent than TPIV 100. We believe TPIV 110 shows great promise and it helps round out our cancer vaccine portfolio.
For more information on TapImmune visit http://www.tapimmune.com (Ticker: TPIV)