A review of market access for Duchenne muscular dystrophy treatments shows that under the pharmacy benefit, about 44% of the lives under commercial formularies are covered with utilization management restrictions. Around 35% of the lives under health exchange formularies are not covered for at least one of the drugs.
Under the medical benefit, about 48% of the lives under commercial policies are covered with utilization management restrictions. Almost 80% of the lives under Medicare policies have access to at least one of the drugs without utilization management restrictions.
For about 72% of the covered lives, payer pharmacy benefit formularies do not require step therapy (ST). Of the lives that require ST, only 1% of the lives require multiple steps. Around 85% of payer-controlled pharmacy benefit covered lives require prior authorization.
In June 2023, the FDA granted accelerated approval to Sarepta Therapeutics, Inc.’s Elevidys (delandistrogene moxeparvovec-rokl) for the treatment of ambulatory people ages 4 and 5 years with Duchenne muscular dystrophy with a confirmed mutation in the DMD gene except for any deletion in exon 8 and/or exon 9 in that gene. The adeno-associated virus vector-based gene therapy is dosed via a one-to-two-hour intravenous infusion. The price for the one-time treatment is $3.2 million.
The FDA in June 2023 approved two new gene therapies for Duchenne Muscular Dystrophy (DMD) and hemophilia A, and major PBMs tell AIS Health, a division of MMIT, that they have not yet decided how to cover the new treatments. If current trends are any indication, health plans will impose strict utilization management requirements and attempt to negotiate outcomes-based reimbursement pacts with the treatments’ manufacturers.
In May 2022, the FDA granted orphan drug designation to Stealth BioTherapeutics Corp.’s elamipretide for the treatment of patients with Duchenne muscular dystrophy. The FDA’s division of neurology also granted the company’s request for a pre-investigational new drug (IND) meeting to discuss a development path for elamipretide in combination with products within the approved therapeutic class of exon-skipping phosphorodiamidate morpholino oligomers, according to the company.
Market Events Drive Changes
In June 2023, the FDA granted accelerated approval to Sarepta Therapeutics, Inc.’s Elevidys (delandistrogene moxeparvovec-rokl) for the treatment of ambulatory people ages 4 and 5 years with Duchenne muscular dystrophy with a confirmed mutation in the DMD gene except for any deletion in exon 8 and/or exon 9 in that gene. In February 2021, the FDA gave accelerated approval to Sarepta’s Amondys 45 (casimersen) for the treatment of DMD in people with a confirmed mutation amenable to exon 45 skipping. In August 2020, the agency gave accelerated approval to NS Pharma, Inc.’s Viltepso (viltolarsen) for people with DMD who have a mutation amenable to exon 53 skipping.
Competitive Market Landscape
There are multiple products in Phase III or later of clinical trials. Treatments in the development pipeline include therapeutic approaches that restore or replace dystrophin and those that treat Duchenne symptoms, such as those that protect muscles by reducing fibrosis and inflammation. Viltepso brings competition to Sarepta’s Vyondys 53 (golodirsen), as they are both indicated for DMD patients who are amenable to exon 53 skipping therapy. Sarepta’s Exondys 51 (eteplirsen) continues to enjoy a competition-free space in the market, as the only agent available for patients amenable to exon 51 skipping therapy.
Pharmacy, Medical Benefit Implications
Drugs for this indication are generally covered under both the pharmacy and medical benefits. Payers require prior authorization, and step therapy requirements may have patients try prednisone and prednisolone first.