Potential Universal Cancer Vaccine Will Start Clinical Trials in Ovarian Cancer
[The article is about Immunovaccine, a Canadian penny stock, but mentions several other small companies working on cancer vaccines]
The Pink Sheet Daily. 2011 Jul 26, J Haas
oncologystat.com
With an IND approval from FDA in hand for a Phase I/II program, Immunovaccine hopes to advance its ovarian cancer vaccine DPX-Survivac quickly and find a partner to acquire either the program or the whole company. Based in Halifax, Nova Scotia, Immunovaccine believes its candidate eventually could become a universal cancer vaccine, treating at least nine different cancers.
Outlining the company's overall strategy at the Biotechnology Industry Organization meeting in Washington, D.C., in June, Immunovaccine Chief Science Officer Marc Mansour said the biotech will test the vaccine first in ovarian cancer. Lack of treatment options for ovarian cancer patients and the short duration of remission patients typically experience following surgery and chemotherapy make this the optimal disease setting for the vaccine, he said.
Immunovaccine's candidate is one of several emerge in the cancer immunotherapy space since the financing environment for such products improved over the past year, thanks largely to FDA's approval of Dendreon's Provenge (sipuleucel-T) for prostate cancer. But the biotech thinks its approach may be especially effective because it is based on attacking an antigen, survivin, commonly found in cancer cells and needed for the cells to survive.
DPX-Survivac combines a survivin-based vaccine in-licensed from Merck KGaA in 2010 with Immunovaccine's proprietary DepoVax technology, which the company claims drives an improved immune response. Merck KGaA was willing to out-license the vaccine, Mansour said, because the pharma wanted to focus on later-stage programs, including the cancer vaccine Stimuvax.
Mansour said the survivin antigens formulated with DepoVax technology activate "those types of T cells that you need floating around looking for cancer cells. They're more active, they're better activated."
Survivin is a tumor-associated antigen present in many cancer cells and not generally expressed in normal cells, according to the company. The National Cancer Institute has classified survivin as a promising cancer antigen because of its specificity to cancer cells - it is found in up to 90% of ovarian cancers. But Immunovaccine's approach is not to block survivin, but to use survivin as a flag to help the immune cells its vaccine activates find and kill cancer cells.
"If you block survivin with a drug, the cell cannot survive. It goes through programmed cell death and it dies," Mansour explained. "What we're doing with our vaccine is teaching the immune system to target cancer cells that express survivin so that the immune cells will circulate and home in on cancer cells that express survivin and kill them."
Besides ovarian cancer, Immunovaccine believes DPX-Survivac could prove effective in melanoma, multiple myeloma and prostate, pancreatic and colorectal cancers.
Having demonstrated in a Phase I trial of another vaccine, DPX-0907, that DepoVax formulations are both safe and active in human subjects, Immunovaccine sought permission from FDA to run a small Phase I trial followed immediately by a larger Phase II study it hopes will generate data to attract potential partners.
The program will begin later this year with a 15-patient open-label dose-ranging study to determine the optimal dose for use in Phase II. The company expects to have that Phase I data by the third quarter of next year, and then begin a 250-patient, placebo-controlled Phase II proof-of-concept trial in the fourth quarter of 2012. The trial will last an expected two and a half years and begin generating interim data in late 2013, Mansour said.
"FDA has bought into this concept of doing a Phase I/II combined and we can do the Phase I and move directly into Phase II without going back to the agency," he said. "That's a big savings in time and money, which for an early-stage biotech is very important."
Immunovaccine, whose shares are traded on the TSX Venture exchange, reported $10.4 million cash on hand at the end of 2010. This included proceeds from a follow-on public offering in which it raised $7.465 million by selling new stock for $1 per share.
Patients in the Phase II trial will be women recently diagnosed with ovarian cancer who have had surgery and chemotherapy. They then will receive the vaccine to see if it will prolong their remission period.
"For a cancer vaccine to work, it has to be used in the early stages of the disease," Mansour explained. "When you have newly diagnosed ovarian cancer patients who will get surgery and then chemotherapy, they wait for about a year and a half and then the cancer will come back. During that period, you can vaccinate."
"The tumor has been eliminated by treatment but there are always cancer cells floating around. They escape treatment, get established and the cancer will come back," he continued. "Those are the kind of cancer cells you are trying to target using your immune system - you're teaching your immune system to target those floating cells and delay the cancer from coming back."
Immunovaccine, which derives some royalty income from a partnership with Pfizer Animal Health, which has licensed the DepoVax technology to enhance its animal vaccines, hopes Phase II data will be sufficiently strong to drive a lucrative big pharma partnership. In the meantime, the company will look to additional platform license deals to increase its income.
"If the Phase II trial is successful, I don't think finding a partner will be a very difficult task," Mansour said. "That's when big pharma will be likely to line up and look to acquire it. And so that's an exit strategy at that point for either the product or the company."
According to data collected from Elsevier Business Intelligence's Inteleos database, there are at least 10 other companies with unpartnered cancer vaccines currently in Phase II of development. These include: Bellicum Pharmaceuticals' BPX-101 for prostate cancer, Quantum Immunologics' breast cancer vaccine, Celldex Therapeutics' CDX-1401 for solid tumors, Immunovative Therapies' AlloStim for various cancer types, Geron Corporation's GRNVAC1 for acute myelogenous leukemia, New Link Genetics' Hyperacute vaccine for prostate and pancreatic cancer, Immatics Biotechnologies' IMA-901 for renal cell carcinoma, Avex Technologies OVax for advanced ovarian cancer, Inovio Pharmaceuticals' PSMA-based prostate cancer vaccine, and Vaxon Biotech's VX-001 for advanced solid tumors and non-small cell lung cancer.
Another method the biotech is using to try to drum up collaboration business is its "DepoVax Challenge," in which it asks other vaccine companies to send a copy of their candidates to be formulated with the DepoVax technology for no charge. Mansour said Immunovaccine has several of these agreements in progress.
"We tell other companies, 'you have a vaccine, obviously it needs enhancements, send us your vaccine and we'll formulate it for you and send it back to you,'" he said. "Then, they get to test it in their animal models and if they like it, we'll talk. This doesn't cost anything; it's a simple research agreement." |
