NEW YORK, March 9, 2026, 10:48 (EDT) 1
- Dianthus shares rose about 22% in morning trade after the company said its late-stage CAPTIVATE CIDP trial hit an interim threshold ahead of schedule. 2
- The biotech reached 20 confirmed responders before 40 patients completed the first part of the study and said cash should last into 2028. 3
Dianthus Therapeutics shares jumped on Monday after the biotech said its late-stage CAPTIVATE study of claseprubart in CIDP, a rare autoimmune nerve disease, met an interim threshold earlier than planned, allowing the program to move forward. The stock was up about 22% in morning trade in New York. 2
The update matters because CAPTIVATE is one of Dianthus’ biggest 2026 catalysts and the company had only in November moved the interim check-in up to the second quarter of 2026 from the second half on faster enrollment. It also lands in a market where argenx already sells Vyvgart for CIDP and Sanofi is running Phase 3 riliprubart studies. 4
Dianthus said it reached the threshold after 20 confirmed responders were recorded before the first 40 patients finished the first part of the study, where all participants received the drug. An independent safety board backed the decision, and the company said there were no related serious infections, no related serious adverse events and no discontinuations tied to the drug. 2
The company now plans to keep the 300-mg under-the-skin dose given every two weeks, ask regulators to drop the higher-dose arm from the second half of the trial, and cut planned enrollment in Part A to 256 patients from 480. That would reduce the number randomized into Part B to 128 from 192, with timing guidance for the main Part B readout due by year-end 2026. 2
Chief Executive Marino Garcia said the interim results “bolster our confidence” in claseprubart’s profile. James Sheffield, Dianthus’ head of CIDP development, said it was “encouraging to see consistency” across several clinical measures. 2
Dianthus paired the trial update with full-year results. The company reported a 2025 net loss of $162.3 million, versus $85.0 million a year earlier, and said it ended December with $514.4 million in cash, cash equivalents and investments, enough to fund operations into 2028. 3
Analyst reaction was upbeat. William Blair analyst Myles Minter called the data a “best-case scenario” at this stage, according to Benzinga, while Clear Street analyst Bill Maughan said the results were “de-risking”; Truist raised its price target to $110 from $63. 5
Still, the update is an early look. Dianthus said the interim analysis was based on a limited number of patients, and cautioned that the result may not predict what the rest of Part A or the randomized Part B study will show. The company also still needs regulators to agree to removing the higher-dose arm. 3
Beyond CIDP, Dianthus said it expects to start a Phase 3 study of claseprubart in generalized myasthenia gravis in mid-2026, with top-line results in the second half of 2028. Top-line data from its Phase 2 trial in multifocal motor neuropathy, or MMN, remain on track for the second half of 2026, and first healthy-volunteer data for DNTH212 are also due in the second half of this year. 3
