Enrollment Now Complete in ZEPHYRUS-1 Trial of Pamrevlumab
The randomized, placebo-controlled trial (NCT03955146) now includes 356 IPF patients across 144 sites worldwide. It aims to evaluate the safety and efficacy of one year of pamrevlumab treatment. According to FibroGen, top-line results are expected by mid-2023.
A second trial in the Phase 3 developmental program for pamrevlumab, called ZEPHYRUS-2 (NCT04419558), is currently enrolling 340 people with IPF. Eligible participants are ages 40–85, and were previously treated with an approved IPF therapy.
ZEPHYRUS-2, which launched in 2020, is testing pamrevlumab in 151 locations globally. One U.S. site, in South Carolina, is now recruiting, along with dozens worldwide.
Pamrevlumab, previously known as FG-3019, is an antibody engineered to block the activity of connective tissue growth factor (CTGF), a protein known to contribute to the formation of scar tissue, or fibrosis, which is the hallmark feature of IPF.
“Completing patient enrollment for ZEPHYRUS-1 brings us closer to delivering evidence that pamrevlumab, an inhibitor of connective tissue growth factor (CTGF), provides clinical benefits for the treatment of IPF and other fibrotic disorders,” Mark Eisner, MD, chief medical officer at FibroGen, said in a press release.
“IPF is a fatal progressive disease, and patients need new treatment options to improve their clinical outcomes,” Eisner added.
The two ZEPHYRUS trials have similar goals of assessing the treatment’s safety and efficacy, compared with a placebo, among IPF patients within the same age range. In both, the primary aim is to assess changes in forced vital capacity (FVC), a lung function parameter that measures the maximum amount of air a person is able to exhale after a deep breath.
Secondary goals include assessing changes in the progression of lung fibrosis and patient-reported measures related to breathing and coughing.
Pamrevlumab will be administered at a dose of 30 mg/kg via an into-the-vein infusion every three weeks, totaling 17 infusions over 48 weeks.
ZEPHYRUS-1 includes patients not currently being treated with other IPF therapies due to intolerance, ineligibility, or other reasons. Such reasons include concerns about treatment risks.
ZEPHYRUS-2, meanwhile, specifically aims to investigate pamrevlumab’s efficacy in patients who previously used other approved IPF therapies, such as Esbriet (pirfenidone) or Ofev (nintedanib), but had discontinued treatment.
Participants in both studies will have the option of entering an open-label extension phase after the end of the one-year core study.
Two Phase 2 trials — PRAISE (NCT01890265) and FGCL-3019-049 (NCT01262001) — supported the treatment’s safety and efficacy. These studies showed that a similar course of treatment used in the ZEPHYRUS trials was able to interrupt the progression of lung fibrosis in IPF patients with mild-to-moderate disease, which was associated with improvements in lung function.
Pamrevlumab has been granted orphan drug and fast track designations by the U.S. Food and Drug Administration (FDA) for IPF, locally advanced unresectable pancreatic cancer, and Duchenne muscular dystrophy.