FibroGen's neuromuscular disorder therapy fails late-stage study

By Sriparna Roy

(Reuters) -FibroGen Inc's treatment for patients with a muscle-wasting disorder that typically binds them to a wheelchair failed to improve measures of upper limb strength, sending the drug developer's shares down 11% on Wednesday.

The therapy, being developed to treat forms of Duchenne muscular dystrophy (DMD), is the second Fibrogen drug to fail a late-stage study in just over a month after its anemia drug roxadustat.

FibroGen was evaluating the DMD therapy, pamrevlumab, in a late-stage trial in patients with non-ambulatory forms of the disorder, versus a placebo.

While measuring the ability to walk is the traditional goal of DMD studies, patients with non-ambulatory DMD are in advanced stages of the disorder and are bound to a wheelchair due to the severity of the disease.

"We have not seen any sort of improvement in functional measurements ever. If this was positive, it would have been the first one ever so I think that also speaks to the technical difficulty of winning in DMD," William Blair analyst Andy Hsieh said.

DMD causes progressive muscle failure that mainly affects boys, with symptoms showing at an early age.

FibroGen plans to present the complete results of the study at an upcoming medical conference.

The company expects to post late-stage data in the third quarter of this year from the other fully enrolled study in ambulatory patients with DMD who cannot walk.

FibroGen is also studying the therapy in idiopathic pulmonary fibrosis, a chronic lung disease, and a type of pancreatic cancer.

(Reporting by Sriparna Roy in Bengaluru; Editing by Shilpi Majumdar and Shounak Dasgupta)