KPL-387 - (PASTORALE)

July 28, 2026: Kiniksa Pharmaceuticals International, plc (NASDAQ: KNSA) reported Q2 2026 results and pipeline updates highlighted by ARCALYST (rilonacept) and KPL-387 in recurrent pericarditis.

ARCALYST: Q2 2026 net product revenue was $243.6 million (~55% YoY growth). The company raised full-year 2026 ARCALYST net product revenue guidance to $980–$995 million (from $930–$945 million). As of end of Q2 2026, ~21% of ~14,000 multiple-recurrence patients were actively on ARCALYST; >5,000 prescribers have written prescriptions; average therapy duration was ~3 years.

KPL-387: Interval analysis from the ongoing Phase 2/3 trial’s Phase 2 dose-focusing portion showed the 300 mg SC once-monthly group had rapid and sustained reductions in pain/inflammation: median time to treatment response 4.0 days (95% CI 3.0–6.0), time to pain response 4.0 days (3.0–6.0), and time to CRP normalization 8.0 days (7.0–9.0). The 300 mg monthly liquid formulation dose was selected for the pivotal Phase 3 trial (PASTORALE), which is now enrolling and dosing; primary endpoint is time to first adjudicated pericarditis recurrence in a randomized-withdrawal design.

KPL-1161: Preclinical; Phase 1 first-in-human trial planned by end of 2026.

Conference call/webcast scheduled for 8:30 a.m. ET on July 28, 2026.