FibroGen Announces Topline Results from LELANTOS-2, a Phase 3 Clinical Study of Pamrevlumab in Ambulatory Duchenne Muscular Dystrophy

– Study did not meet the primary endpoint –

– Pamrevlumab was generally safe and well tolerated –

SAN FRANCISCO, Aug. 29, 2023 (GLOBE NEWSWIRE) -- FibroGen, Inc. (NASDAQ: FGEN) today announced topline data from the Phase 3 LELANTOS-2 trial of pamrevlumab for the treatment of ambulatory patients with Duchenne muscular dystrophy (DMD) on background systemic corticosteroids. The study did not meet the primary endpoint of change in the North Star Ambulatory Assessment (NSAA) total score from baseline to week 52 (placebo-corrected mean difference -0.528 points; 95% CI -2.308 to 1.251; p=0.5553). Secondary endpoints measured by change from baseline at week 52 in 4-stair climb velocity, 10-meter walk/run test, time to stand, time to loss of ambulation, and proportion of patients with greater than 10 seconds in the 10-meter walk/run test were also not met.

“We are deeply disappointed that the LELANTOS-2 study did not meet its primary endpoint,” said Thane Wettig, Interim Chief Executive Officer, FibroGen. “We are grateful for the courageous efforts of patients, their caregivers, the advocacy community, and the trial investigators who have contributed to this important clinical study. We are committed to sharing all learnings from this trial with the Duchenne community and hope that there are insights that may help future efforts to develop treatments for this devastating disease.”

Preliminary safety data showed that pamrevlumab was generally safe and well tolerated. The majority of treatment emergent adverse events were mild or moderate. Treatment-emergent serious adverse events were observed in 8.3% of patients in the pamrevlumab group and 2.8% of patients in the placebo group.

FibroGen is in the process of evaluating the totality of the data, including other pre-specified endpoints, to determine the next steps for the program. The Company plans to communicate the full results of the LELANTOS-2 study at an upcoming medical forum.  

About LELANTOS-2
A total of 73 boys with ambulatory DMD ages 6 to <12 years were enrolled in LELANTOS-2, a global, Phase 3, randomized, double-blind trial of pamrevlumab or placebo in combination with systemic corticosteroids. The primary endpoint of the study was ambulatory function measured by change in the North Star Ambulatory Assessment (NSAA) total score from baseline to Week 52. Secondary endpoints assessed from baseline to Week 52 included changes in 4-stair climb velocity, 10-meter walk/run test, time to stand, time to loss of ambulation, and proportion of patients with greater than 10 seconds in the 10-meter walk/run test. In LELANTOS-2, patients were dosed with pamrevlumab (35 mg/kg IV on Day 1 and every two weeks thereafter with last dose at Week 52) or placebo.