On March 2, 2019, Principia Biopharma Inc., a late-stage biopharmaceutical company dedicated to bringing transformative oral therapies to patients with significant unmet medical needs in immunology and oncology, today announced Phase 2 clinical data from the Believe-PV study for PRN1008 as part of the Late-breaking Research: Clinical Trials program at the American Academy of Dermatology (AAD) annual meeting in Washington D.C. PRN1008 is being developed for the potential treatment of pemphigus, including pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Confirming interim clinical results previously reported, the Phase 2 study reached the primary efficacy measurement of control of disease activity (CDA) on low dose corticosteroids.
“The primary goal of treating patients with pemphigus is to control the disease and heal the skin, however a significant challenge is to avoid adverse events associated with the prolonged use of corticosteroids that are typically required to achieve clinical improvement,” stated Dr. Dedee Murrell, Professor and Head of the Department of Dermatology at The St. George Hospital Clinical School, University of New South Wales in Sydney, Australia and the lead principal investigator. “PRN1008 has the potential to rapidly and effectively treat patients’ disease, while significantly reducing the exposure to moderate to high corticosteroid doses.”
The open-label Phase 2 study enrolled 27 patients with newly diagnosed and relapsed, mild to severe pemphigus (including both PV and PF). Twenty-four patients were treated with oral PRN1008 and low dose corticosteroids (LDCS; <0.5mg/kg/day) for twelve weeks, with twelve weeks of follow-up. The primary endpoint was CDA (where new lesions cease to form, and existing lesions begin to heal) at Week 4. Other secondary endpoints included complete remission rates and reduction in anti-desmoglein autoantibody levels.