Pulmonary fibrosis patients taking pamrevlumab had less than half the decline in a measure of lung function over 48 weeks than those receiving a placebo, a Phase 2 clinical trial indicates.
The results support previous findings suggesting that pamrevlumab can slow the progression of the disease, according to its maker, FibroGen.
Researchers had predicted that pamrevlumab patients would have a decline of 2.85 percent in a measure known as forced vital capacity. FVC is the amount of air a person can forcibly exhale from the lungs after taking the deepest breath possible. The actual FEV results that pamrevlumab patients achieved met the forecast.
Meanwhile, the research team had projected a 7.17 percent decline in forced vital capacity among the placebo group over the 48 weeks — and FibroGen suggested that the results trended in that direction.
Pamrevlumab inhibits connective tissue growth factor, or CTGF. The protein plays a key role in the development of fibrotic disorders, such as interstitial pulmonary fibrosis, or IPF. FibroGen is also evaluating pamrevlumab as a treatment for pancreatic cancer and Duchenne muscular dystrophy.
The Phase 2 study (NCT01890265) covered 103 patients. Pamrevlumab met its primary effectiveness objective of achieving the 2.85 percent decline in forced vital capacity that researchers had predicted — one that was considerably lower than the 7.17 percent they had predicted for the placebo group.
A finding that was in line with the primary objective was that the pamrevlumab group’s decline in forced vital capacity averaged 129 ml, compared with 308 ml in the placebo group.
As in previous studies, the trial participants tolerated pamrevlumab well, researchers said.
“I am pleased to see positive Phase 2 results with pamrevlumab — an antibody against CTGF, a new target in fibrosis — which has a good safety profile and the potential to provide alternative, much-needed new treatment options for IPF patients,” Dr. Luca Richeldi, head of pulmonary medicine at Agostino Gemelli University Hospital in Rome, said in a press release.
The company also conducted two sub-studies to assess the safety of a combination of pamrevlumab and two approved IPF therapies — Esbriet (pirfenidone) and Ofev (nintedanib).
The sub-studies involved 57 patients. Thirty-six who were on a stable dose of Esbriet were randomized to receive either pamrevlumab or a placebo for 24 weeks. And 21 who were on a stable dose of Ofev received either pamrevlumab or a placebo for the same period. Patients tolerated both combinations well.
“The positive results from this randomized, placebo-controlled Phase 2 study build on our previous clinical data which demonstrated the potential of pamrevlumab to slow the progression of IPF with a good safety and tolerability profile,” said Dr. Peony Yu, FibroGen’s chief medical officer.
“We are conducting further analyses and look forward to presenting additional data from this study in the months ahead,” she said. “We believe these results support a Phase 3 program in patients suffering from this debilitating and deadly disease.”
FibroGen will present these and further results at the European Respiratory Society International Congress in Milan in September.
The company plans to meet with U.S. Food and Drug Administration officials soon on a strategy for achieving regulatory approval of pamrevlumab as an IPF treatment.