Analysts poured cold water, but FDA gives a fast-pass for Sanofi's new Pompe disease drug
Analysts didn’t love the results from Sanofi’s pivotal Pompe disease study, but the FDA has evidently seen enough promise to give it an expedited look.
On Wednesday, the French giant announced that the agency has given priority review for their Pompe disease drug avalglucosidase alfa, handing them a PDUFA data for May 18 and a chance to get a further head start on Amicus and the rival drug now in Phase III.
Sanofi has had a toe hold in Pompe disease since it bought out Genzyme in 2011. The Cambridge biotech developed Myozyme and Lumizyme, the first and so far only treatments for the rare lysosomal disorder. Caused by a missing or dysfunctional sugar-processing enzyme known as GAA, the disease leads to a buildup of sugars in cells throughout the body, often causing irreversible muscle damage.
Myozyme and Lumizyme provides an artificial copy of the enzyme, slowing but not stopping damage.
Sanofi designed the new enzyme to more easily squeeze inside cells, in theory allowing it to process more sugar and further slow damage.
In a 100-patient Phase III study, though, the new enzyme failed to prove it was superior to the original drug in improving respiratory function. It came close, with a P value of .06, and still managed to meet the primary endpoint of non-inferiority. But with other options on the horizon, the results left analysts unimpressed.
“Today’s announcement was in line with our expectations that…. Ph.3 data would be underwhelming,” SVB Leerink’s Joseph Schwartz wrote in June, when the results came out. Amicus, he said, would be “likely the best-in-class next-generation” enzyme replacement drug.
Analysts projected the drug would be approved but that it would not become a huge moneymaker. Cowen’s Steve Scala projected a €100 million in revenue in 2025, compared to €1.25 billion for Lumizyme.
Of course, much of their skepticism comes from the often necessary but crude art of cross-trial comparisons, with Schwartz comparing open-label Amicus results to Sanofi’s placebo-controlled data. Amicus will get a chance to prove that, unlike Sanofi, they can achieve superiority over Lumizyme when they release their Phase III trial results.
Those are expected to come in the first quarter of the year. John Reed and the R&D team over at Sanofi will likely be watching closely.