Duchenne Muscular Dystrophy Treatment Pamrevlumab Receives Orphan Drug Designation

Elias Kouchakji, MD, Senior Vice President, Clinical Development and Drug Safety, fibrogen

Elias Kouchakji, MD

The FDA has granted FibroGen’s anticonnective tissue growth factor (CTGF) antibody, pamrevlumab, orphan drug designation for the treatment of Duchenne muscular dystrophy (DMD).

Pamrevlumab, a first in class antibody developed to inhibit the activity of connective tissue growth factor, is currently being studied in an open-label, single arm phase 2 trial (NCT02606136) to estimate its safety and efficacy in nonambulatory patients with DMD.

“We are pleased to have received orphan drug designation from the FDA for pamrevlumab in the treatment of DMD. There is a high unmet medical need for patients suffering from this debilitating disease needing a new treatment option” Elias Kouchakji, MD, senior vice president, clinical development and drug safety, FibroGen, said in a statement.¹ “All 21 non-ambulatory DMD patients in our ongoing phase 2 study with pamrevlumab have completed the first 52 weeks of treatment. We are evaluating a number of clinical parameters in this study, including lung function, cardiac function, and upper extremity muscle function, and tissue fibrosis. We look forward to the continued development of this investigational therapeutic.”

In the trial, each patient will receive 35 mg/kg of pamrevlumab every 2 weeks by intravenous infusion for up to 156 weeks. Efficacy assessments will be performed routinely throughout the course of the study, and all patients will be monitored closely for safety.

The primary outcome measure focuses on the annual change in percent predicted annual forced vital capacity, while the secondary outcome measures include the changes in forced expiratory volume, maximum inspiratory pressure, maximum expiratory pressure, peak expiratory flow, peak cough flow, left ventricular ejection fraction, Performance of Upper Limb score, grip strength, pinch strength, Brooke scale for upper extremity, cardiac fibrosis score assessed by MRI, and upper arm (bicep) muscle fat and fibrosis assessed by MRI.

Pamrevlumab is also currently being studied in phase 2 clinical studies for the treatment idiopathic pulmonary fibrosis and pancreatic cancer.

REFERENCE

1. FibroGen Receives Orphan Drug Designation from the U.S. FDA For Pamrevlumab for the Treatment of Duchenne Muscular Dystrophy [news release]. San Francisco: FibroGen, Inc.; April 15, 2019. phx.corporate-ir.net/phoenix.zhtml?c=253783&p=irol-newsArticle&ID=2394469. Accessed April 15, 2019.