Amryt earns a priority review in a rare disease that makes patients' skin fragile as butterfly wings
A year after flashing mixed Phase III data, an Irish drugmaker notorious for owning some of the country’s most expensive drugs is getting an expedited look at its treatment for epidermolysis bullosa (EB) — a rare disease where a patient’s skin becomes as fragile as butterfly wings.
The FDA granted priority review to Amryt’s Oleogel-S10, accelerating the drug’s assessment time from 10 months to six months, the company said on Thursday. The agency set its PDUFA date for Nov. 30, and CEO Joe Wiley said launch plans are “well advanced.”
Amryt originally picked up the drug, also known as episalvan, from the small German drugmaker Birken. The drug was already EMA-approved for partial thickness wounds, but Amryt saw potential in EB and rushed it into a Phase III trial almost immediately.
The FDA’s decision will be based on data from Amryt’s EASE trial, in which 41.3% of patients who received Oleogel-S10 saw first complete closure of EB target wounds within 45 days. That compares to 28.9% of patients in the control group, translating to a 44% increase in the probability of target wound closure (and a p-value of 0.013), according to Amryt.
The drug missed on key secondary endpoints, though, including the proportion of completely closed target wounds within the 90-day treatment period. Investigators say they saw a greater reduction of total body wound burden in those on Oleogel-S10 — measured by a commonly used scale and total surface area of EB partial thickness wounds — but the difference wasn’t statistically significant.
At the time, Wiley celebrated the results as a “significant milestone” for the company, and he’s already branded the EB version of the drug as Filsuvez.
There are currently no approved treatments for EB, which affects roughly 1 in 20,000 people. Chronic and relapsing wounds leave patients vulnerable to repeated infections, according to the FDA, and some end up with fibrosis, deformities and cutaneous carcinogenesis.
“Skin lesions are associated with itching and pain, the latter aggravated during dressing changes,” the agency said in a 2019 statement, upon releasing new guidance to help companies develop treatments.
Several others are working on treatments for the rare condition, including Abeona, which last summer reinitiated a Phase III trial for its cell therapy after a brief pause due to Covid-19. Krystal Biotech said it completed enrollment in a Phase III study for its own dystrophic EB candidate back in March, and expects top-line results in Q4. Castle Creek Pharmaceuticals bought out Fibrocell Science back in December 2019, and is now in Phase III with its recessive dystrophic EB candidate FCX-007.
Filsuvez would make Amryt’s fourth approved product, after Episalvan and two drugs the company picked up from Aegerion: Myalept and Juxtapid. The latter two have consistently ranked among the most expensive drugs in the US. Myalept now is fourth on GoodRx’s list of the most costly drugs in the country.