Shares of Climb Bio Inc. fell 7% to $14.00 in pre-market trading on Thursday, reversing an earlier rally following the release of Phase 1 clinical data for CLYM116, the company's anti-APRIL monoclonal antibody targeting IgA nephropathy.
The data, disclosed in an 8-K filing and a press release, showed that a single 320 mg subcutaneous dose of CLYM116 achieved near-complete suppression of the APRIL protein. Sustained reductions of 60–75% in IgA and Gd-IgA1 levels were observed over a 12-week period, with no serious adverse events reported. Climb Bio characterized the results as demonstrating a "best-in-class APRIL suppression profile."
The decline followed weeks of investor anticipation, as Climb Bio had pre-announced the September 3 R&D Spotlight Webcast in its August quarterly report, allowing traders to position ahead of the data release. Analysts at Truist, Guggenheim, Oppenheimer, and RBC Capital already maintain Buy ratings on the stock, limiting potential for fresh analyst-driven upside to offset profit-taking.
The company's Phase 2 NAVIGATE-2 trial in IgA nephropathy remains ongoing, with initial data not expected until the first half of 2027. Earlier technical indicators, including a double-top sell signal flagged in early August, had also pointed to near-term price pressure.
In broader markets, the S&P 500 rose 0.3%, the Dow Jones Industrial Average gained 0.6%, and the Nasdaq added 0.1%. Climb Bio's stock, while still well above its 52-week low of $1.54, has retreated from its 52-week high of $18.33.
