The answer comes Feb. 10, when Cell Therapeutics travels to suburban Washington D.C. to make its case for pixantrone's approval to a panel of cancer experts convened by the U.S Food and Drug Administration.
The FDA's advisory panel will be reviewing data from a phase III study of pixantrone in patients with advanced, aggressive non-Hodgkin's lymphoma. The "EXTEND" study was conducted under a Special Protocol Assessment from the FDA, and the results, as presented by Cell Therapeutics to date, appear to be positive.
Of course, clinical data from "positive" phase III trials always looks great when pitched by the company developing the drug. The truth about a drug's efficacy is often something different and far less robust, especially after FDA reviewers finish picking apart the data line by line.If the pixantrone data closet does have skeletons -- and let's face it, no drug skates through an FDA review unscathed -- here's where they might be found: 1. Missing patients? Cell Therapeutics designed the pixantrone EXTEND study in 2003 - 2004 with the intention of enrolling 320 patients. In March 2008, however, Cell Therapeutics announced that it halted enrollment at 140 patients. Will FDA accept the results from this study, given that only 40% of the planned patients actually enrolled? How does the drastically smaller number of patients effect the statistical powering of the study? And given the fact that the study is open label -- meaning doctors and patients know who's getting pixantrone and who's getting a comparator drug -- what amended rules were put in place to say that 140 patients were sufficient to prove pixantrone's efficacy?