By Brady Huggett
Cell Pathways Inc., saying it may have mapped a better route to FDA filing for Aptosyn, initiated a Phase III study of the drug in combination with Taxotere in patients with advanced non-small-cell lung cancer.
The study will enroll 600 patients. Cell Pathways will begin the enrollment process through US Oncology Inc. - the network of 72 integrated cancer centers spread across the country - and is expected to enroll at least 420 patients through the network. The trial will evaluate Aptosyn, Cell Pathway's lead investigational drug, in combination with Taxotere vs. Taxotere alone, with the primary endpoint being increased survival.
"The trial is double blind and placebo controlled, which is odd for a cancer trial, but we can do it here," said Robert Towarnicki, president, CEO and chairman at Cell Pathways. "Because of the addition of Aptosyn to the standard of care, we can make this trial blinded. That's important for people to know. We don't want people thinking we are giving cancer patients placebo; what we are doing is giving them the standard of care [alone or with Aptosyn]."
Following the full enrollment, the study will follow the patients for up to one year or to survival. Towarnicki said the average patient seen in the trials has a six-month survival window, so the goal is to increase that survival period.
"I think [complete enrollment] could take as long as 18 months," he said. "But we are going to try to do it quicker than that." He added that another 15 sites outside the US Oncology network would be added to reach the total of 600 patients.
Aptosyn is part of a class of compounds called Selective Apoptotic Antineoplastic Drugs. This class of drugs is being developed to selectively induce apoptosis in precancerous and cancerous cells with minimal effects on normal cells. Cell Pathways is investigating Aptosyn in several precancerous and cancerous conditions by itself and in combination with conventional chemotherapy agents.
In August 1999, Cell Pathways filed a new drug application for Aptosyn to treat familial adenomatous polyposis. On Sept. 25, 2000, the company received a not-approvable letter from the FDA saying there were deficiencies in the filing and that the safety and efficacy data were inadequate. The company's stock was crushed by the news, dropping more than $20 in value, or about 69 percent, and closed the day at $9.312. Cell Pathways has not yet decided its next step concerning Aptosyn for that indication. (See BioWorld Today, Sept. 26, 2000.)
"We are evaluating the regulatory and business environment around [this indication]," Towarnicki said. "It is unclear to us the regulatory path. But we have not given up on it yet. We continue to evaluate the landscape to see if it is worth it to continue with it or not."
Aptosyn is being investigated across the cancer board. Besides the Phase III trial in lung cancer just initiated and the familial adenomatous polyposis program still being evaluated, Cell Pathways has trials with Aptosyn - either alone or in combination - for sporadic colonic polyps, Barrett's esophagus, prostate cancer, breast cancer and solid tumors. It also has the product CP-461 in a Phase Ia trial for healthy adults and Ib for patients with solid tumors.
Even with all other Aptosyn indications, Towarnicki said the Phase III in non-small-lung cancer is important for the company.
"This gives Aptosyn a new target in an approval pathway for the drug with a clear endpoint," he said. "The oncology pathway to approval is a more tried and proven pathway for Aptosyn."
Cell Pathways' stock (NASDAQ:CLPA) gained 29.69 cents Friday to close at $6.234. n