ChemGenex has agreed to meet with the FDA discuss developing a validated assay test for determining which patients might benefit from its experimental chronic myeloid leukemia (CML) treatment Omapro (omacetaxine mepesuccinate).
"This is a comparative efficacy claim that somebody is making here, so the level of proof has to be there," said Richard Pazdur, director of the Office of Oncology Drug Products in the Center for Drug Evaluation and Research. "The message is that the agency is trying to get across is that attention has to be paid to these in vitro diagnostics." ChemGenex announced the initiative shortly after the FDA's Oncology Drugs Advisory Committee voted 7-1 to require such testing before approving Omapro, which is targeted at CML patients who have failed Novartis' Gleevec (imatinib).
Speaking of Novartis, the ChemGenex situation is another important example of the role companion diagnostics can play in bringing new drugs to market.
In August 2009, Novartis’ two-year effort to revive its Prexige pain pill (after it was rejected by
With a test showing that a certain drug will be safe, Nohaile said, “We can go to doctors and say it moves it out of the realm of choice into the realm of malpractice if you don’t use this drug.
Exciting stuff -- but once these diagnostics are developed, will payers reimburse? In the wake of the payer disquietude over spending $400 on a diagnostic test to determine whether a patient should be given warfarin, it’s very much an open question. (Even more peculiar considering that conservative estimates project using the warfarin diagnostic -- specifically called out in the amended FDA label -- will prevent 85,000 serious bleeding events and 17,000 strokes annually in the United States. And this “safer use” is estimated to save $1.1 billion annually.
Stay tuned.
