Highlights

  • Third quarter 2026 total revenue was $286.0 million, compared with $180.9 million, and net income was $47.3 million, compared with $18.4 million.
  • Kiniksa now expects 2026 ARCALYST net product revenue of between $1.045 billion and $1.050 billion, up from $980 million to $995 million.
  • Cash, cash equivalents and short-term investments were $568.8 million at September 30, 2026, with no debt.
  • KPL-387 pivotal Phase 3 data in recurrent pericarditis are expected in the second half of 2027.

Kiniksa Pharmaceuticals International, plc (NASDAQ: KNSA) shares were trading at USD 89.48 on October 27, 2026, up 22.61%, with a relative volume at time of 3.49. The biopharmaceutical company reported third quarter 2026 results on October 27, 2026, raised its 2026 ARCALYST net product revenue guidance, and gave an expected timeline for pivotal data from its KPL-387 trial.

Kiniksa is incorporated in England and Wales, and its principal executive offices are at 105 Piccadilly in London. Its agent for service is Kiniksa Pharmaceuticals Corp. in Lexington, Massachusetts. The company is a biopharmaceutical company developing and commercializing therapies for diseases with unmet need, with a focus on cardiovascular indications. Its commercial product is ARCALYST, an interleukin-1 alpha and interleukin-1 beta blocker approved by the FDA for recurrent pericarditis, cryopyrin-associated periodic syndromes and deficiency of IL-1 receptor antagonist. Its pipeline includes KPL-387 and KPL-1161.

Third Quarter Results

ARCALYST net product revenue was $286.0 million for the third quarter of 2026, and total revenue was $286.0 million, compared with $180.9 million for the third quarter of 2025. The press release described the revenue as approximately 58% year-over-year growth.

Total operating expenses were $231.7 million, compared with $156.8 million. Cost of goods sold was $27.8 million, compared with $20.3 million, which the company linked to increased ARCALYST sales. Collaboration expenses were $105.8 million, compared with $63.3 million. Research and development expenses were $32.8 million, compared with $24.2 million, mainly from increased KPL-387 clinical activity. Selling, general and administrative expenses were $65.4 million, compared with $49.1 million, mainly from investment in ARCALYST commercialization. Total operating expenses included $13.1 million of non-cash share-based compensation expense.

Net income was $47.3 million, compared with $18.4 million for the third quarter of 2025. On the earnings call, management said operating income was $54.2 million.

ARCALYST Commercial Metrics

As of the end of the third quarter of 2026, approximately 23% of the 14,000 annual multiple-recurrence patients were actively on ARCALYST treatment. More than 5,450 prescribers have written ARCALYST prescriptions for recurrent pericarditis since launch. Average total duration of ARCALYST therapy in recurrent pericarditis was approximately 3 years.

Pipeline

Kiniksa is enrolling and dosing patients in PASTORALE, the Phase 3 pivotal trial of KPL-387 in recurrent pericarditis, and expects data in the second half of 2027. The company said it hopes to bring the treatment to patients in the 2028/2029 timeframe. PASTORALE is a double-blind, placebo controlled, randomized withdrawal study enrolling up to approximately 85 patients, with a primary endpoint of time to first-adjudicated pericarditis recurrence. KPL-387 is investigational, and the FDA granted it Orphan Drug Designation for pericarditis in October 2025.

Kiniksa is also conducting a supplemental Phase 2 study of patients transitioning from standard therapies to KPL-387 monotherapy. It expects to start a Phase 1 first-in-human trial of KPL-1161, which has a target profile of quarterly subcutaneous dosing, by the end of 2026. KPL-1161 is in preclinical development.

Financial Guidance

Kiniksa expects 2026 ARCALYST net product revenue of between $1.045 billion and $1.050 billion, compared with prior guidance of between $980 million and $995 million. It expects 2026 research and development expenses of between $160 million and $170 million and selling, general and administrative expenses of between $270 million and $280 million. The company expects its current operating plan to remain cash flow positive on an annual basis.

The company's forward-looking statements list risks that include delays or difficulty in enrolling patients in clinical trials, the potential for negative, inconclusive or commercially uncompetitive trial data, and reliance on third parties to conduct research and trials.