Shares of Kiniksa Pharmaceuticals Ltd. (KNSA) surged 7.77% in pre-market trading on Tuesday following the company's strong second-quarter 2025 financial results and increased full-year guidance. The biopharmaceutical firm, which focuses on developing and commercializing novel therapies for patients with debilitating autoimmune and autoinflammatory diseases, impressed investors with its performance and optimistic outlook.

Kiniksa reported Q2 2025 earnings per share (EPS) of $0.23, surpassing the analyst estimate of $0.18. The company's revenue also exceeded expectations, coming in at $156.797 million, well above the projected $145.218 million. This strong financial performance was driven by robust product sales, particularly from its flagship drug ARCALYST.

In a significant move that likely contributed to the stock's pre-market rally, Kiniksa raised its full-year 2025 guidance for ARCALYST net product revenue. The company now expects ARCALYST to generate between $625 million and $640 million, up from the previous guidance of $590 million to $605 million. This upward revision suggests growing confidence in the drug's market penetration and commercial success. Additionally, Kiniksa announced the initiation of a Phase 2/3 clinical trial for KPL-387 in recurrent pericarditis, with Phase 2 data expected in the second half of 2026, indicating progress in its pipeline development.