Armed with what it sees as impressive clinical data and bolstered by long-standing ties to the Niemann-Pick disease type C (NPC) community, Zevra Therapeutics is confident that its new drug Miplyffa can become the “foundation and the cornerstone” for treatment of the debilitating and very rare disease going forward.
Late last month, the FDA approved Miplyffa, also known as arimoclomol, as the first therapy for NPC. The drug was cleared in combination with the enzyme inhibitor miglustat, which has long been used as the primary, albeit off-label, treatment for NPC patients.
NPC prevents the body from moving and using cholesterol and other lipids in cells, in turn causing a buildup of fats in the liver, spleen or lungs. The disease can take a serious toll on patients’ speech, cognition, swallowing, movement and fine motor skills, and people with the disease only live for about 13 years on average, according to the FDA’s original approval release.
In the U.S., there are roughly 300 to 350 patients currently being treated for NPC, though Zevra estimates there could be as many as 900 addressable NPC patients total, the company’s chief commercial officer, Josh Schafer, said in an interview.
“Our goal is to ultimately be able to bring Miplyffa to all of those patients,” Schafer explained.
Ahead of Miplyffa’s approval last month, Zevra spent the year building out its commercial organization and leveraging the existing marketing experience it’s garnered with its urea cycle disorder (UCD) drug Olpruva.
UCDs are metabolic genetic disorders that are oftentimes treated by the same prescribing community and physicians that will now be helping patients access Miplyffa, Schafer pointed out. Zevra picked up Olpruva through its $91 million acquisition of rare disease compatriot Acer Therapeutics last August.
NPC patients in the U.S. already getting therapy for their disease largely rely on around 40 centers of excellence across the country, including teaching institutions and children’s hospitals, Schafer said.
While the CCO couldn’t divulge exact numbers around Zevra’s commercial force, he noted that the company has built out a “very bespoke” field team designed to reach those 40-or-so existing treatment centers. The overall field force includes a sales team, medical liaisons and a market access unit working with payers.
Further, Zevra reckons some 80% of NPC patients already receive miglustat for their disease. This should make the transition to Miplyffa relatively painless and could even clear up reimbursement challenges patients previously faced when trying to access the medicine off-label, Schafer explained.
Given the dearth of NPC treatments previously, patients have been “very much aware of Miplyffa before it was approved, and those patients have been waiting eagerly for its approval,” Schafer said.
Schafer described the NPC community as “one of the more galvanized and organized patient groups out there,” with Zevra benefiting from “long-standing” relationships across multiple different NPC organizations.
Miplyffa will become available to patients some eight to 12 weeks after the med’s Sept. 20 approval, Schafer pointed out.
As for the drug’s cost, Zevra is pricing Miplyffa at $9.50 per milligram, with final dosing dependent upon the weight of the individual patient. Schafer described the cost as “commensurate with the value that we bring to patients.”
Citing the 12-month clinical trial underpinning Zevra’s recent approval, Schafer noted that Miplyffa is “the only drug out there that has been demonstrated to halt the progression of disease, as opposed to treating just the symptoms of disease.”
While it will take a few more weeks for new patients to start on the drug, a number of patients from Zevra’s clinical trial have already been shifted over to an open-label study or an expanded access program, ensuring continuity of treatment.
As it stands, there are more than 70 patients in Miplyffa’s expanded access program in the U.S. and about 150 total patients enrolled in the program worldwide, Schafer said. Those patients are currently being treated across 13 sites, where Zevra is already seeing “great momentum” within the expanded access program and beyond, the CCO explained.
“It’s really a reflection of what Miplyffa brings, but also the side effect profile and the ability to continue to bring benefits to these patients over a very long period of time,” the CCO added.
In the trial that won Zevra its approval, Miplyffa plus miglustat halted disease progression through 12 months of treatment as shown by a 0.2-point decrease from baseline on the rescored 4-domain NPC Clinical Severity Scale (R4DNPCCSS). By comparison, patients in the trial’s control arm saw 1.9 points of progression on the scale, which examines metrics identified as most relevant for NPC patients including ambulation, speech, swallowing and fine motor skills.
Zevra’s chief medical officer, Adrian Quartel, M.D., explained that: “One point is a difference between sitting in a wheelchair and walking aided … it’s a difference between being able to feed yourself or needing someone [to help],” the CMO explained in the interview.
Miplyffa’s approval was followed up in short order by a nod for a second NPC treatment in IntraBio’s Aqneursa, which snagged an FDA green light to treat neurological symptoms of NPC in adults and kids Sept. 25.
Still, Zevra isn’t sweating the competition.
“It’s really just hard to believe that you have two approvals within one week after literally decades of nothing available—so we’re thrilled for patients and the NPC community,” Schafer said.
The CCO reiterated that Zevra expects Miplyffa to become the standard for the disease given its progression-halting potential, with the belief that additional therapies will be prescribed based on patients’ individual symptoms and needs.