Kiniksa raises ARCALYST sales forecast to $1.050 billion after 58% growth
Key Facts
Kiniksa Pharmaceuticals raised its 2026 net revenue forecast for ARCALYST to a range of $1.045 billion to $1.050 billion, from $980 million to $995 million previously, after the drug generated $286.0 million in net product revenue in the third quarter, an increase of about 58% year over year. The company reported results on October 27, and Chief Executive Sanj Patel said strong commercial execution during the quarter boosted adoption among patients and physicians. He added that revenue "puts ARCALYST on track to become a drug with sales exceeding $1 billion this year." The forecast increase for the second time in 2026 reflects continued growth in the drug, after the company raised its range in the second quarter to $980–$995 million from $930–$945 million previously. The new forecast also exceeded the $1 billion threshold for the first time in the range the company announced for this year.
Kiniksa's total revenue was $286.0 million in the third quarter, compared with $180.9 million in the same period of 2025, while the financial table showed net product revenue of $285.970 million, against $180.855 million a year earlier. In the second quarter of 2026, ARCALYST posted net revenue of $243.6 million, up about 55% year over year, according to the company's results at the time. The comparison shows quarterly revenue growth accelerating from about 55% in the second quarter to about 58% in the third. Patel said adoption improved among both patients and physicians, which the company linked to commercial execution during the quarter. In its previous update, the company had attributed patient growth to new and repeat prescribers and said an increase in the number of patients receiving treatment contributed to its higher annual forecast.
Kiniksa said about 23% of the 14,000 patients annually who experience multiple recurrences of pericarditis were receiving ARCALYST at the end of the third quarter. It added that more than 5,450 prescribers had written prescriptions for the drug to treat recurrent pericarditis since its launch. Average total treatment duration was about 3 years, the company said. These figures provide the company's indicators of the scale and persistence of use among patients, alongside sales growth. In January, the company reported that ARCALYST's 2025 net sales were $677.5 million, up about 62% year over year, and that its initial 2026 forecast was $900 million to $920 million. Since that initial forecast, Kiniksa has raised its range in the second quarter and again with its third-quarter results.
Operating expenses rose to $231.7 million in the third quarter of 2026, from $156.8 million in the same period a year earlier. They included collaboration expenses of $105.8 million, research and development expenses of $32.8 million, and selling, general and administrative expenses of $65.4 million. The company attributed the increase in research and development primarily to higher clinical activity for the KPL-387 program, and linked the increase in selling and administration to investment related to marketing ARCALYST. Kiniksa said it had $568.8 million in cash, cash equivalents and short-term investments as of September 30, 2026, with no debt. It expects its current operating plan to continue generating positive cash flow on an annual basis.
Kiniksa continues to enroll patients and administer doses in the pivotal Phase 3 PASTORALE trial of KPL-387, which is evaluating a once-monthly subcutaneous dose. The company expects the trial data in the second half of 2027. In its second-quarter results, it said Phase 2 data showed a rapid and sustained reduction in pain and inflammation at a dose of 300 mg administered subcutaneously once a month, the dose selected for Phase 3. It also then expected KPL-387 to be available to patients within the 2028/2029 timeframe.
In trading, Kiniksa shares closed at $76.73 on October 23 and then at $72.98 on October 26, 2026, according to EL7 data. The latest close came before the third-quarter results published on October 27. The trading data provided did not include the stock's movement after the results were released. The company had linked the higher forecast to growth in ARCALYST revenue and expanding adoption, while the next KPL-387 trial data remain expected in the second half of 2027.