Phase 2 BELIEVE study part B: Efficacy and safety of rilzabrutinib for patients with pemphigus vulgaris.

Keywords: bullous disorders; disease control; pemphigus EN bullous disorders disease control pemphigus 852 855 4 09/19/22 20221001 NES 221001 Pemphigus vulgaris (PV) is a potentially life-threatening, blistering autoimmune disease commonly treated with first-line corticosteroids (CS).1,2 The oral, covalent Bruton tyrosine kinase (BTK) inhibitor rilzabrutinib3 was validated in proof-of-concept BELIEVE part A phase 2 study (NCT02704429) at 400-600 mg bid doses (±CS) for 12 weeks (mean CS = 0.18 mg/kg/day) plus 12 weeks follow-up in newly diagnosed/relapsing, mild-to-severe PV.4 Part B expanded these findings in patients aged 18-80 years with biopsy-proven, newly diagnosed (<=6 months from diagnosis) or relapsing PV, and Pemphigus Disease Area Index (PDAI) score 8-60.5 Patients initially received oral rilzabrutinib 400 mg qd with optional dose escalation to 400 mg bid at/after week 2, and further to a maximum 600 mg bid dose at/after week 4. Although results were limited by a small number of patients, rilzabrutinib (±CS) demonstrated a consistently favourable benefit-risk profile with broader rilzabrutinib doses and longer treatment in newly diagnosed/relapsing pemphigus patients. One patient with chronic, relapsing pemphigus (PDAI 36 at baseline) and worsening disease failed to achieve CDA despite rilzabrutinib dose escalation, was hospitalized at week 9 to receive intravenous immunoglobulin/rituximab, and discontinued the study. [Extracted from the article]