SAN DIEGO -- Genta ( GNTA) may seek a second shot at marketing approval for its experimental cancer drug Genasense, but don't expect things to turn out any better than the first time. Still, some investors seemed eager to take a flier on Genta's chances at resurrection. The stock closed up 67 cents, or 48%, to $2.05 on Monday. But that was down from its intraday high of $2.40, or up 74%, reached before a presentation on a form of leukemia at 2:15 p.m. EDT. More than 62 million shares traded hands in a company with a 73 million-share float and a 30-day daily average volume of 2.9 million shares. At an oral presentation at the American Society of Hematology meeting Monday, the Berkeley Heights, N.J.-based drugmaker said the addition of Genasense to chemotherapy increased "major" responses in patients with advanced chronic lymphocytic leukemia (CLL) in a phase III study. But this increase in response had no clinically meaningful effect on patients in terms of increasing their survival or even delaying the progression of disease. And the Genasense-chemotherapy combination used in the study is relatively outdated, with newer drugs, including Genentech's ( DNA) Rituxan, producing better responses in similar CLL patients. During Monday's presentation, the Genasense study's lead investigator, Dr. Kanti Rai of Long Island Jewish Medical Center, did not specifically endorse a Food and Drug Administration filing based on this clinical data. While he believes in the promise of Genasense in CLL, Rai said different dosing schedules and/or studies of the drug in newly diagnosed (read: less sick) CLL patients is needed. Genta has not yet said publicly whether it will seek FDA approval for Genasense in CLL, but the down-and-out company has little to lose. In May, Genasense was rejected by an FDA advisory panel as a melanoma treatment, sending shares tumbling into the single digits. At present, Genta has lost its corporate partner, Aventis ( AVE), and is running short of cash. A separate phase III study in multiple myeloma, also presented over the weekend at the ASH meeting, was a failure.
The phase III study enrolled 120 patients who were given a combination of Genasense plus chemotherapy; another 121 patients were given chemotherapy alone. All patients in the study were diagnosed with advanced CLL, which means they had received, and failed, prior therapies. Nineteen patients, or 16%, in the Genasense arm of the study achieved a major response -- defined as a complete response or so-called nodular partial response, compared to with eight patients, or 7%, in the control arm. This result, the study's primary endpoint, was statistically significant, albeit not robustly so with a so-called p value of 0.039.
A p value of 0.05 is required for a study to reach statistical significance, but strong data typically have a p value of less than 0.01. But a more conventional primary endpoint in CLL studies looks at overall response rate, defined as a complete response, nodular partial responses and partial response. When the Genasense data were analyzed this way, overall response in the Genasense arm was 41%, less than the 45% overall response rate in the control arm. Also, patients in the Genasense arm of the study progressed (their disease worsened) at a median time of 6.1 months, faster than the 8.9 months for patients in the control arm. Overall survival data were not analyzed, pending further maturing of the data. Despite a series of setbacks this year that have left Genta reeling, the company seems intent to push ahead with Genasense's development. No doubt, persistence sometimes pays off. But for Genta, the second time will not likely be the charm.