Fast Track Designation Granted to Idiopathic Pulmonary Fibrosis Treatment, Pamrevlumab

The US Food and Drug Administration (FDA) has granted a fast track designation to FibroGen, Inc’s pamrevlumab for the treatment of patients with idiopathic pulmonary fibrosis (IPF).

“This Fast Track designation reflects recognition of the great need for a new therapeutic to help patients diagnosed with IPF to reduce the burden and progression of this debilitating disease and another positive step in developing pamrevlumab for the treatment of IPF,” Elias Kouchakji, MD, senior vice president of Clinical Development and Drug Safety at FibroGen, said in a recent statement. “We look forward to advancing pamrevlumab into phase 3 studies early next year.”

Data from a randomized, double-blind, placebo-controlled phase 2 clinical trial served as the basis for the designation. The main objective of the trial was to see if the treatment improved lung function; to do this, investigators measured the change in forced vital capacity (FVC) at weeks 12, 24, 36, and 48 and compared that data with the beginning of the trial.

Secondary objectives for the trial were to assess the progression of lung fibrosis, which they measured by using quantitative high-resolution computed tomography at weeks 24 and 48. The treatment’s safety and impact on quality of life were also evaluated.

The study consisted of 1 experimental arm and a placebo comparator. In the experimental arm, participants were administered pamrevlumab 30 mg/kg; 10 mg/ml, single dose vials via intravenous infusion every 3 weeks for a total of 16 infusions over 45 weeks. Participants in the substudy were administered the same dose for a total of 8 infusions over 21 weeks.

In the placebo arm, participants were administered sterile, clear aqueous solution, 10 mg/ml, single dose vials via intravenous infusion every 3 weeks for a total of 16 infusions over 45 weeks. Participants in the substudy were administered the same dose for a total of 8 infusions over 21 weeks.

The investigators found that pamrevlumab halted the progression of lung fibrosis and improved lung function in patients with IPF. Specifically, at week 24, they found that in patients treated with pamrevlumab, quantitative lung fibrosis volume was 24.8 ml compared with the placebo group, in which fibrosis volume was 86.4 ml.

Fibrosis in patients treated with pamrevlumab reached a volume of 75.4 ml compared with patients treated with placebo, who had a volume of 151.5 ml—more than double the fibrosis burden—after 48 weeks. As shown by a reduction in the rate of decline in FVC, a decrease in fibrosis progression with pamrevlumab also correlated with better lung function.

A first-in-class antibody, pamrevlumab was developed to inhibit connective tissue growth factor activity, which is commonly found in fibrotic and proliferative disorders. Previously, pamrevlumab was granted orphan drug designation for IPF and pancreatic cancer. The treatment received a fast track designation for the treatment of patients with locally advanced unresectable pancreatic cancer as well.

FibroGen is working on advancing the drug towards phase 3 clinical development for IPF.