Dianthus Therapeutics (NASDAQ:DNTH) executives used a Biotech Summit 2026 discussion to outline upcoming clinical catalysts for its lead complement inhibitor program and provide updated timing on pipeline plans, while also emphasizing what they see as potential competitive advantages in neuromuscular indications.
Management highlighted 2025 as a “transformational” year
Chief Executive Officer Marino Garcia said 2025 brought the company’s first patient data in myasthenia gravis (MG), which he characterized as a “best-case scenario” from an efficacy standpoint. He also pointed to the in-licensing of DNTH212 from China-based Leads Biolabs, describing it as a bifunctional fusion protein that targets BDCA2 to reduce type I interferon and targets BAFF/APRIL on the other side.
Near-term focus: CIDP Phase 3 interim responder analysis
Garcia described two key 2026 catalysts for clasiprubart, Dianthus’ lead program, which he characterized as a highly potent active C1s inhibitor with a long half-life. The first is an interim responder analysis from the company’s Phase 3 CIDP study (“CAPTIVATE”), which he said is expected in the second quarter of 2026—an acceleration from prior guidance in the second half of the year due to what he called strong recruitment.
In discussing benchmarks for CAPTIVATE, Garcia repeatedly referenced Sanofi’s riliprubart (also an active C1s inhibitor) and its Phase 2 data in CIDP. He said Dianthus is looking for Part A open-label efficacy “at least similar” to riliprubart, citing a target range of roughly 40%–50% or greater responder rate. Responders, as described on the call, are patients who achieve an additional one-point improvement on the INCAT score and then move into the randomized, blinded Part B portion.
Garcia said disclosure will be limited because the trial is ongoing, but he told investors to watch three items in the company’s public communication:
- Whether the Part A dose remains 300 mg every two weeks. Garcia said keeping the dose would be interpreted as a sign the regimen is working as hoped.
- Whether the 600 mg arm is dropped from Part B. He argued removing the higher-dose arm could signal confidence in the 300 mg regimen and could speed the trial, potentially narrowing Sanofi’s timeline advantage if riliprubart is delayed.
- Recruitment ratio assumptions for Part A versus Part B. Garcia said Dianthus targets 192 patients in Part B and conservatively could need up to 480 patients in Part A, implying a ~40% responder ratio.
He also contrasted CAPTIVATE with argenx’s ADHERE design, saying Dianthus allows IVIG-refractory patients and does not require a washout period intended to induce relapse. Instead, Garcia said patients are switched within seven days, consistent with what he described as riliprubart’s approach and what he said argenx is doing with efgartigimod.
MMN: positioning versus argenx’s empasiprubart
Asked about multifocal motor neuropathy (MMN), Garcia said argenx’s empasiprubart produced “really impressive” Phase 2 data, with Phase 3 results expected by argenx in the fourth quarter of 2026 based on his remarks. Garcia said Dianthus expects at minimum similar efficacy, while emphasizing differences in administration and a potential safety advantage.
He said empasiprubart is administered intravenously monthly, while Dianthus aims for a subcutaneous self-administered auto-injector every two weeks. Garcia also argued that because empasiprubart blocks both the classical and lectin complement pathways, it could raise questions about immune defense against encapsulated bacteria, adding that he believes the FDA may place a boxed warning on such a profile. He contrasted this with Sanofi’s Enjaymo (sutimlimab), which he described as a pure classical pathway inhibitor on the market for four years without a boxed warning.
On potency, Garcia said Dianthus ran head-to-head testing using the Quidel MicroVue assay that argenx published for classical pathway inhibition. He said clasiprubart appeared at least six times more potent at IC50 in Dianthus’ hands, and “30 times more potent” at IC90 in that experiment, while acknowledging the open question of whether higher potency translates into higher clinical efficacy. He said the company’s Phase 2 MMN study includes both 300 mg and 600 mg doses.
MG program: FDA interaction and Phase 3 design considerations
Garcia said the company has held an end-of-Phase 2 meeting with the FDA and is awaiting written feedback, after which it plans to disclose more details. He said Dianthus learned from its Phase 2 MG study that a lack of a QMG screening criterion may have contributed to a higher-than-expected placebo response. In a post hoc analysis, he said applying a minimum QMG threshold (he cited testing a 10-point minimum) brought placebo response closer to historical levels and widened the active-versus-placebo separation for the 300 mg dose to a three-point MG-ADL difference.
Garcia also described an internal “mini experiment” in which placebo patients rolled into open-label clasiprubart without a loading dose, and he said the response after two doses supported testing an every-four-week regimen. He said he is “fully confident” a once-monthly auto-injector dosing schedule could be the eventual commercial regimen.
Cash runway and upcoming DNTH212 milestones
Chief Financial Officer Ryan Savitz said the company ended the year with $514 million in cash, which he said extends runway into 2028 and covers key milestones discussed for both clasiprubart and DNTH212. For DNTH212, Garcia said the company expects to announce which three indications it will pursue in the first half of 2026, report top-line results from a single ascending dose (SAD) healthy volunteer study in China in the second half of 2026, and report results from a second part of that study testing doses in systemic lupus erythematosus (SLE) patients in the first half of 2027.
About Dianthus Therapeutics (NASDAQ:DNTH)
Dianthus Therapeutics, Inc, a clinical-stage biotechnology company, develops complement therapeutics for patients with severe autoimmune and inflammatory diseases. It is developing DNTH103, a monoclonal antibody, which is in Phase 2 clinical trial, for the treatment of generalized myasthenia gravis, multifocal motor neuropathy, and chronic inflammatory demyelinating polyneuropathy. Dianthus Therapeutics, Inc was founded in 2019 and is headquartered in New York, New York.
