Climb Bio Starts CLYM116 Phase 2 Dosing in IgAN

The Tip Desk · November 11, 2026 · 4 min read

Cash, cash equivalents and marketable securities were $227.6 million as of September 30, 2026, with a net loss of $14.6 million, or $0.18 a share, in the third quarter.

Climb Bio, Inc. (CLYM), a clinical-stage biotechnology company developing therapeutics for immune-mediated diseases, said it has initiated dosing in the NAVIGATE-2 Phase 2 trial of CLYM116 in IgA nephropathy, after saying in the prior quarter that it anticipated that trial to begin dosing in the third quarter of 2026.

NAVIGATE-2 is a randomized, open-label study evaluating an 800 mg loading dose of CLYM116 followed by 400 mg every 8 weeks or every 12 weeks, intended to support advancement of a 12-week regimen into Phase 3. Enrollment is ongoing. The company said it anticipates initial NAVIGATE-2 data in the first half of 2027 and initiation of a global Phase 3 trial in 2027, pending regulatory feedback.

Those plans follow Phase 1 results in healthy volunteers from complementary randomized, double-blind, placebo-controlled studies in Australia and China that enrolled 46 and 42 participants. Across both studies, pharmacokinetics were linear with no target-mediated drug disposition across the effective dose range, and more than 90% free APRIL suppression was sustained through 12 weeks after a single subcutaneous dose of 480 mg or higher. Following a single 800 mg dose, the company said it observed about a 70% reduction in Gd-IgA1 and about a 60% reduction in IgA at 12 weeks. CLYM116 was generally well tolerated, with no dose-limiting toxicities, treatment-related serious adverse events, or hypogammaglobulinemia. The company said those pharmacokinetic and pharmacodynamic data support a 12-week dosing regimen.

On the budoprutug side, the company presented initial data from the PrisMN Phase 2 primary membranous nephropathy trial at ASN Kidney Week 2026, after saying in the prior quarter that it anticipated initial data from the low-dose cohort at a medical meeting in the fourth quarter. At Week 12, the 200 mg cohort demonstrated B-cell depletion, reductions in PLA2R antibody levels, and immunologic remission. Initial data from the ongoing 600 mg cohort suggested greater drug exposure and deeper peripheral B-cell depletion compared with 200 mg. Enrollment is ongoing in a third 1000 mg cohort. Additional data from all cohorts, including longer-term follow-up, are expected in 2027.

Initial data from the ongoing global Phase 1b trial of budoprutug in systemic lupus erythematosus showed dose-dependent B-cell depletion and reductions in disease activity. As of an October 7, 2026 data cutoff, 17 participants had enrolled across 10 mg, 30 mg and 100 mg single-dose cohorts. B-cell depletion reached a mean reduction of 84% at Week 12 in the 100 mg cohort. Reductions of 4 points or more in SLEDAI-2K scores were observed at Week 12 in seven of 12 participants in the 30 mg and 100 mg cohorts, compared with none of the five participants in the 10 mg cohort. The company said budoprutug was generally well tolerated, with no serious adverse events, discontinuations due to adverse events, or infusion-related reactions. Enrollment is ongoing in a final 200 mg cohort, and dosing continues in a parallel Phase 1b/2a trial in China. Additional data from both studies are anticipated in 2027.

Additional Phase 1b data in immune thrombocytopenia from the 500 mg and 1000 mg cohorts are to be presented at the American Society of Hematology annual meeting in December 2026. Following positive single-dose data for the subcutaneous formulation in May 2026, the company said it plans to initiate a subcutaneous study in autoimmune disease patients and anticipates initial subcutaneous data in 2027.

Cash, cash equivalents, and marketable securities were $227.6 million as of September 30, 2026, versus $160.7 million as of December 31, 2025. Based on its current operating plan, the company said it expects that balance to fund operations into the second half of 2028.

Research and development expenses were $11.0 million for the three months ended September 30, 2026, compared with $9.1 million a year earlier. General and administrative expenses were $5.8 million in both periods. Other income, net was $2.3 million. Net loss was $14.6 million, or $0.18 a share, versus $12.9 million, or $0.19 a share, a year earlier.

President and Chief Executive Officer Aoife Brennan said the company is building momentum across CLYM116 and budoprutug, and that it is poised to enter 2027 with two programs, multiple anticipated data readouts, and the potential to initiate pivotal studies.