Shares in Genitope Corp. lost more than a quarter of their value on news that the company's pivotal cancer vaccine study would have to continue as planned, with another data analysis scheduled a year from now.
Regarding the results, "there's obviously a little disappointment around here," Chairman and CEO Dan Denney said during a conference call. "I suspect there's a little disappointment out there among the people who have invested in the company. But I can tell you that I'm in no way discouraged, and I don't think anyone here at Genitope is discouraged, about the results."
Nevertheless, the news that the Phase III trial of the MyVax Personalized Immunotherapy has not yet met its endpoint of progression-free survival at an initial planned interim analysis caused the stock (NASDAQ:GTOP) to drop $3.41 Tuesday, or 27.9 percent, and close at $8.80. The study is continuing based on the recommendation of an independent Data Safety Monitoring Board that reviewed efficacy findings from the evaluation in follicular non-Hodgkin's lymphoma patients.
Denney said a number of factors could have caused the trial to miss hitting statistical significance at this point, including the chance that a number of patients could still be in their immunization series or just finishing that process. He declined to specify the number of progression events that had been reached going into the first analysis, but at the next interim efficacy analysis, all patients will have finished their immunization series and be a year beyond randomization.
"We knew the bar was high, and we were aware of all the factors that could impact our ability to see results this time," he said. "But all in all, we felt it was worth taking this look, that there was a high enough likelihood of success in this trial. The bar is always higher at the first look, and it's harder to see results at the first look. As you go along in the trial, it's easier to see a positive result. That's what we're going to do."
The next interim efficacy analysis is scheduled for the middle of next year, and the Redwood City, Calif.-based company said it had sufficient cash to carry it beyond that point. Before going commercial with MyVax, assuming it eventually receives FDA approval, John Vuko, Genitope's chief financial officer, said the company likely would seek additional financing. At the end of the last quarter, Genitope reported about $109.4 million in reserves.
"We've got a ton of work to do in terms of getting this company ready for commercialization," Denney said, "and we're going to be moving ahead and doing all the things we said we were going to be doing, most of which were going to have to happen irrespective of whether we had a positive result yesterday or not."
The study is comparing treatment-na ve patients who receive MyVax to those treated with a nonspecific immunotherapy control. It completed enrollment this spring and is being conducted at 34 North American oncology centers to test whether active immunotherapy for follicular non-Hodgkin's lymphoma can delay or prevent recurrence of disease in patients in remission following an initial course of chemotherapy.
According to its protocol, patients' tumor burdens first were reduced with chemotherapy consisting of cyclophosphamide, vincristine and prednisone (CVP), and those who respond to eight cycles with at least a 50 percent reduction in tumor burden and maintain that response through a subsequent six-month rest period are randomized 2:1 to receive series of seven immunizations of MyVax or placebo over a 24-week period. Between 270 and 300 patients are participating in the trial, Vuko told BioWorld Today, which began in November 2000.
MyVax is a patient-specific active immunotherapy based on the genetic makeup of a patient's tumor and is designed to activate the patient's immune system to identify and attack cancer cells. Vuko said the company owns all its rights and plans to market MyVax on its own domestically, should it receive approval, and partner overseas rights down the road.
In addition to the pivotal trial, MyVax also is in an ongoing Phase II rollover study for patients who entered the Phase III study but failed to achieve at least a partial response after eight cycles of CVP chemotherapy or progressed during the subsequent six-month rest period. In that study, MyVax is being tested in conjunction with Rituxan (rituximab, from Genentech Inc. and Biogen Idec Inc.). Several additional Phase II trials in B-cell non-Hodgkin's lymphoma patients are closed to enrollment and remain in long-term follow-up.