These results were recently presented in a series of poster presentations at the American Thoracic Society (ATS) 2018 in San Diego.
“We are excited to present additional analyses of the PRAISE Phase 2b trial that confirm and expand our understanding of positive safety and efficacy results with pamrevlumab, with statistically significant treatment effects in slowing IPF progression with encouraging results in both lung function (FVC) and in lung fibrosis (QLF) for the first time in a controlled study. This study demonstrates the therapeutic potential of pamrevlumab and, brings us one step closer to helping IPF patients,” Elias Kouchakji, MD, senior vice president of clinical development and drug safety at FibroGen, said in a press release.
Pamrevlumab, developed by San Francisco-based FibroGen, targets a specific factor — called connective tissue growth factor (CTGF) — known for its role in promoting fibrosis progression-related diseases, including IPF.
The PRAISE Phase 2b trial (NCT01890265) randomized 103 patients with mild to moderate IPF to receive either 30 mg/kg of pamrevlumab, delivered directly into the vein, or a placebo every three weeks. Treatment occurred over 45 weeks for a total of 16 infusions.
The study’s main objective was lung function, measured as changes in forced vital capacity (FVC) at weeks 12, 24, 36, and 48 compared with the beginning of the study. Additional objectives evaluated the progression of lung fibrosis, measured by quantitative high-resolution computed tomography (qHRCT), a noninvasive imaging technique, at weeks 24 and 48.
Researchers also assessed changes in health-related quality of life and safety.
Results showed that treatment with pamrevlumab halted lung fibrosis progression relative to the placebo group — quantitative lung fibrosis volume was 24.8 ml for pamrevlumab-treated patients versus 86.4 ml for the placebo group at week 24.
After 48 weeks, fibrosis in pamrevlumab-treated patients reached a volume of 75.4 ml, while placebo-treated patients had more than double the fibrosis burden, a volume of 151.5 ml.
A decrease in fibrosis progression with pamrevlumab correlated with better lung function, as shown by a reduction in the rate of decline in FVC.
“Data from HRCT analysis show a strong correlation between changes in fibrosis with the changes in FVC in patients treated with pamrevlumab, suggesting the promise of this antibody as an effective and well-tolerated therapy for IPF patients,” said Jonathan G. Goldin, MD, PhD, the trial’s lead investigator and a professor of radiology at UCLA Medical Center.
“These exciting results in a placebo-controlled Phase 2 study clearly demonstrate that quantitative imaging can be incorporated into IPF clinical trials and show that pamrevlumab appears to have a positive and measurable effect on disease pathology,” he said.
For a complete list of the four posters presented by FibroGen at ATS 2018, visit this link.