Kiniksa Pharmaceuticals International (KNSA) investor relations material

Business and financial overview

• Reported Q2 net revenue of $243 million, marking the largest quarter-on-quarter growth to date and increased 2026 net revenue guidance to $980–995 million.

• Maintains strong cash reserves of $525 million at Q2 end and has a history of profitability.

• ARCALYST remains the primary commercial asset, with significant market opportunity remaining in recurrent pericarditis.

• Gross-to-net ratio declined to 7.2% in Q2, mainly due to changes in co-pay programs and patient support optimization.

• Focus remains on balancing near-term earnings with pipeline investment for long-term value creation.

Market penetration and growth drivers

• ARCALYST has achieved 21% penetration in the two-plus recurrence patient group, with substantial room for growth in both this and the first recurrence group.

• Physician education, targeted DTC campaigns, and AI-driven physician targeting are key growth drivers.

• Only 14% of patients are aware of ARCALYST, but 80% of those who inquire receive a prescription.

• Prescriber base is expanding, with 5,000 out of 25,000 relevant physicians having prescribed ARCALYST.

• Utilization in first recurrence patients has grown to 20% of prescriptions, up from 15% a year ago.

Product lifecycle and patient management

• Median ARCALYST treatment duration is about three years, reflecting the chronic nature of recurrent pericarditis.

• About 45% of patients who discontinue ARCALYST restart therapy, typically after symptom recurrence.

• Risk scores help predict disease duration and guide treatment length, supporting a shift to individualized, long-term therapy.

• Real-world and trial data confirm that premature cessation leads to high recurrence rates.