The FDA should approve the first disease-modifying treatment for Duchenne Muscular Dystrophy

On July 18, twelve young men in America hope to celebrate the five-year anniversary of their participation in a clinical trial for a drug called Eteplirsen.  They also hope that, by then, over 1000 other patients—or about 13 percent of the Duchenne Muscular Dystrophy population—will get a green light from the U.S. Food and Drug Administration (FDA) to begin receiving treatments as soon as enough of the drug can be manufactured.

Duchenne Muscular Dystrophy is genetic condition caused by missing information processors in the dystrophin gene that leads to muscle wasting, complete loss of mobility and premature death.   

{mosads}Eteplirsen is designed induce the production of a vital protein, dystrophin, that helps worked muscles recover.  Exon skipping technology used to develop Eteplirsen can be tweaked slightly to help different subsets of Duchenne patients.

Without access to a drug to slow the progression of the disease, Scott Griffin is scared for his son Gabe. “My son is going to have tubes coming in and out all part of his body, with a steel rod shoved in his back, his Achilles heel cords cut, not being able to roll over, not being able to lift his head up. I don’t think it gets much worse than that.”

President Ronald Reagan spoke about how first generation treatments for AIDS could slow the progression until more advanced and more effective treatments could be developed.

“It makes no sense, and in fact it’s cruel, to keep the hope of new drugs from dying patients.”

Fortunately for Duchenne patients, Dr. Janet Woodcock, the current FDA Director of the Center for Drug Evaluation and Research, is well aware of President Reagan’s words. In a 2012 hearing before the U.S. House Committee on Energy and Commerce, Dr. Woodcock reminded the committee how the FDA approached AIDS.     

“I have had several people who are involved in the AIDS epidemic say to me if we had treated that as business as usual, we would never have solved this epidemic, we would have never gotten effective drugs available.”

A recent meeting of the FDA’s Peripheral and Central Nervous System Drugs Advisory Committee was held to evaluate Eteplirsen.  

Duchenne patients presented the FDA with a first-of-its-kind Patient Centered Outcomes Report. Patients reported decreases in spontaneous falls and the use of mobility devices like wheelchairs or scooters, increased ability to participate in activities of daily living such as using the restroom independently or getting in bed, and the ability to walk again after lower limb fractures.

Safety concerns are next to zero. Patients and doctors say the drug works.   

Congressman Mike Fitzpatrick (R-PA) read from a letter signed by 108 colleagues in the U.S. House of Representatives about how the agency should apply the Accelerated Approval standard and flexibilities across review divisions consistently.   

“FDA has been successful at applying flexibility in oncology and HIV/AIDS to speed patient access to apparently safe treatments, and the need and opportunity to adopt innovative and flexible approaches to the review of rare disease drugs has never been greater than it is today.  Patients are waiting.”  

Mr. Fitzpatrick’s letter also noted that “it is critical the FDA take into account the views and experiences of patients as part of the review process.”

The FDA is considering Eteplirsen approval under its Accelerated Approval pathway for serious and life-threatening conditions.  To be approved, the drug needs to demonstrate a “meaningful advantage over available therapies” and “demonstrate an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit.”   

Despite the testimony of Duchenne patients and a plethora of doctors, the panel delivered a split recommendation to the FDA—one favoring non-approval. Like AIDS, Duchenne Muscular Dystrophy should not be treated as “business as usual.”  Those interested in advancing promising therapies to terminally ill patients should focus on the FDA this month.  

Michael Staley is a Senior Policy Advisor at Waller Lansden Dortch & Davis.  He served as chief of staff to former U.S. Representative Spencer Bachus from 2007-2014.  Michael advises clients on a range of issues including federal drug approval policy. He is actively planning his second cross-country bicycle ride to raise Duchenne awareness as a board member of the Birmingham-based Hope for Gabe Foundation.  For more information about Ride4Gabe, go to www.ride4gabe.com