Commodore Capital LP Reports 9.9% Stake in Alto Neuroscience, Inc. (ANRO)

Commodore Capital LP, together with its master fund and managing partners Michael Kramarz and Robert Egen Atkinson, has filed a Schedule 13G/A for Alto Neuroscience, Inc. (ANRO). As of March 31, 2026, the filers reported beneficial ownership of 3,588,180 shares of Common Stock, representing a 9.9% ownership stake in the company. This position consists of 2,723,196 shares of Common Stock held directly and 864,984 shares underlying pre-funded warrants. The filing notes that the warrants are subject to a beneficial ownership limitation of 9.99%, effectively excluding an additional 2,671,370 shares from the current beneficial ownership calculation. The filers indicate that the securities were acquired in the ordinary course of business and not for the purpose of influencing or changing control of the issuer. This filing represents a significant increase from previous reports, where ownership was recorded as zero, marking a major new institutional position in the biopharmaceutical firm.