Placebo use in Pfizer trial raises fears

􀀓 Talks continue with pharmaceutical giant on modifying trial protocol

Use of a placebo in the new clinical trial of the experimental cancer drug SU11248 has sparked an effort by the Life Raft Group to revamp the trial to a more humane standard.

The heart of the issue: Why dying cancer patients who failed Gleevec therapy should be given a sugar pill.

The pharmaceutical giant Pfizer, maker of SU11248, produces such familiar products as Listerine mouthwash, arthritis pain reliever Celebrex, and the erectile pill Viagra. But it has relatively little experience with cancer treatments; indeed, the company’s Web site (www.pfizer.com/main.html) lists treatments for 33 medical conditions – but not cancer.

Following a 90-minute telephone discussion Oct. 30 with Pfizer, Life Raft General Counsel Tom Overley and Executive Director Norman Scherzer went to Pfizer corporate headquarters in New York City on Nov. 11 and met with Krystyna Gurstella, director of professional and public relations, worldwide oncology; Dr. Chris Blakeley, forward development team leader for SU11248, and Susan Yarin, corporate media relations.

The goal was to formally introduce the Life Raft Group and to continue discussion of the phase III SU11248 trial. Talks continued Nov. 25 at the Life Raft Group office in Wayne, New Jersey.

Although many details about the clinical trial were discussed, the key issues remain the inclusion of a placebo for a third of the trial participants, and the lack of a plan for expanded access to the drug.

The current protocol calls for GIST patients with disease progression on Gleevec to be taken off of Gleevec for three weeks before entering the SU11248 trial. Upon entry, they would be randomly assigned to either a placebo or treatment group. They would be reassessed every six weeks.

Those in the placebo group who developed new tumors, or whose overall tumor mass grew at least 20 percent (this in addition to whatever progression they had while on Gleevec and while off Gleevec waiting to enter the trial) would be considered for crossover into the treatment group.

At the most recent meeting, Pfizer agreed that those in the placebo group whose overall physical condition had deteriorated below minimum trial admission standards would nonetheless be given access to the drug.

In addition, Pfizer agreed to work with the Life Raft Group to find historical data and, if necessary, accumulate current data that would provide sufficient documentation about the reality of progression of GIST patients without treatment. If successful, the objective would be to ask the FDA to modify the trial by eliminating the placebo requirement.

The Life Raft Group remains very concerned about the use of a placebo for GIST patients who have no other treatment options. Further talks are planned.