In wake of Reata buyout, Biogen's key launch Skyclarys passes muster in EU

Roughly half a year after Biogen’s $7.3 billion buyout of rare disease specialist Reata Pharmaceuticals, the companies’ blockbuster bid for Reata’s Friedreich’s ataxia (FA) drug Skyclarys is starting to take shape.

Skyclarys—which won its first approval in the United States last March—received a thumbs up from the European Commission this week. The green light specifically clears the way for Skyclarys to treat FA in European patients ages 16 and up, Biogen said in a press release Monday.

With Skyclarys’ latest approval, the drug becomes the first cleared to treat the rare, genetic and progressive neurodegenerative disease FA in Europe. 

FA is the most common inherited ataxia, according to Biogen. Patients often develop initial symptoms during childhood, including progressive loss of coordination, muscle weakness and fatigue. As the disease progresses, many patients also must grapple with vision impairment, hearing loss, problems with speech and swallowing, diabetes, scoliosis and serious heart conditions.

Skylcarys won its initial approval last year in the U.S., where Biogen estimates there are around 8,300 FA patients, according to Toby Ferguson, the company’s head of the neuromuscular and movement disorders development unit. In Europe, meanwhile, Biogen is looking at a patient pool of roughly 7,600, Ferguson said in a recent interview.

The European Commission based its approval on results from the late-stage MOXIe Part 2 trial, which found patients on Skyclarys scored “significantly” lower on the modified Friedreich’s Ataxia Rating Scale (mFARS) versus placebo at the study’s 48-week mark. Each component from the mFARS assessment—from upper and lower limb coordination to ability to swallow and upright stability—favored Skylcarys over placebo, Biogen said.

“Fundamentally, you feel and function better than you would without the drug,” Ferguson said of Skylcarys’ trial results. “That’s fundamentally different than it has been in the past.”

Up until now, treatment for FA has largely been symptomatic.

“You attend to the gradual declining movement, and you use such things as walkers,” Ferguson explained.

As Ferguson likes to put it, “approximately a year of disease progression is preserved when you take this drug.”

Skyclarys passed muster with U.S. regulators last March, several months before the drug’s parent company was bought out by Biogen. The approval, which appropriately arrived on 2023’s rare disease day, marked the first approval in Reata’s 21-year history. At the time of the U.S. approval, Reata said it aimed to launch in Europe in early 2024—a plan which now appears to be on track.

Analysts have projected the drug could generate $1.5 billion in 2030 sales.