Drugmakers Seek More Flexibility from FDA in Developing DMD Drugs

Drugmakers and patient groups are pressing the FDA for more leeway on approaches to developing drugs for Duchenne Muscular Dystrophy, saying a June draft guidance doesn’t go far enough.

In comments on the draft, BioMarin asks the agency for more flexibility in conducting clinical trials, such as allowing tests to be performed in a patient’s home, as traveling to a test site can be a burden for some patients.

BioMarin and Pfizer also take issue with the FDA’s recommendation that trials include as many biomarkers as feasible to establish clinically meaningful endpoints and that drug approvals might be accelerated if intermediate endpoints appear to reasonably predict efficacy. This could limit an approved drug to a specific subpopulation when other patients could benefit as well, the drugmakers say.

Pfizer urges the FDA to consider approving labeling indications for a broader patient population than the one studied unless there is an unacceptable safety risk and suggests the FDA to delete the word “strongly” in a recommendation that trials be randomized and placebo-controlled.

Parent Project Muscular Dystrophy, the group that created its own draft guidance a year before the FDA issued its draft, says it understands the recommendation but wants flexibility to conduct other types of trials when placebo studies aren’t practical. The Duchenne Alliance argues that randomized, placebo-controlled trials for DMD are impractical, unnecessary and unethical.

Bristol-Myers Squibb wants the FDA to clarify whether toxicity studies are needed in DMD children prior to initiating a trial and whether toxicology data are needed to support clinical trials. The comments were among 12 submitted to the FDA by the Aug. 10 deadline.

Read the drugmakers’ responses here: www.fdanews.com/08-12-15-bms.pdf; www.fdanews.com/08-12-15-pfizer.pdf; and www.fdanews.com/08-12-15-biomarin.pdf. — John Bechtel