Johns Hopkins, Roswell Park Cancer Institute and Duke University have announced data at the ASCO meeting in Chicago from a 200 man phase II clinical trial of a blood vessel-blocking drug called tasquinimod. This “anti-angiogenesis” drug constricts the blood supply to prostate tumors by blocking new blood vessel development. The study showed that tasquinimod slowed the rate of disease progression, however ther was no survival data presented.
The trial was a multicenter trial which was conducted at seven institutions. The trial enrolled advanced prostate cancer patients. The subjects were given a once-daily pill for four weeks. At six months, 57 percent of men taking tasquinimod had no disease progression as compared with 33 percent taking a placebo. Overall, the drug added approximately 12 weeks of time that the disease did not worsen (progression-free survival).
The most common side effects experienced by the subjects included gastrointestinal problems, fatigue and bone pain. There were some rare occurrences of heart attack, stroke and deep vein thrombosis in the study subjects.
“Given these results, we feel it is reasonable to move forward with Phase III studies,” says Michael Carducci, M.D., professor at the Johns Hopkins Kimmel Cancer Center, who will lead the next phase of an international study of the drug. “After exploring the drug as a single agent, we may study it in combination approaches with other prostate cancer drugs.”
Tasquinimod works by stopping new blood vessel development around the tumor, but it does not make existing vasculature disappear.
One thing to remember, slowing down disease progression has never been shown to extend survival time. So, the serious question is what are the real potential benefits of tasquimimod and how do they balance out against the increases in potential morbidity issues? These are some serious questions which do need to be evaluated prior to spending large quantities of money on developing this drug.
Funding for the study was provided by Active Biotech, manufacturer of tasquinimod, and the U.S. Department of Defense.
Based on abstracts and presentations made at the annual meeting of the American Society of Clinical Oncology (ASCO), June 4-8, in Chicago.
Joel T Nowak, MA, MSW