Third Harmonic Bio Announces Phase 1 Clinical Results for THB335 and Provides Corporate Strategic Update

Core Viewpoint - Third Harmonic Bio, Inc. has announced positive Phase 1 clinical trial results for THB335, supporting its advancement into Phase 2 trials for chronic spontaneous urticaria (CSU) while also initiating a strategic review to maximize shareholder value [1][2] Clinical Results - The Phase 1 clinical trial included single ascending dose (SAD) with 48 participants and multiple ascending dose (MAD) with 32 participants, evaluating safety, tolerability, pharmacokinetics, and pharmacodynamics of THB335 [3] - THB335 demonstrated a half-life of approximately 40 hours, allowing for once daily dosing, with dose-dependent increases in exposure observed across all cohorts [4] - Significant reductions in serum tryptase, a biomarker for mast cell activation, were noted in MAD cohorts, with reductions ranging from 13% to 84% at Day 15 [5] Safety Profile - THB335 was generally safe and well tolerated, with isolated, transient asymptomatic transaminase elevations observed in three subjects, which management does not believe to be drug-related [6] - Adverse events included hair color changes and reductions in hemoglobin and neutrophil counts, which were dose-dependent and resolved during follow-up [7] Next Steps for THB335 - The company plans to continue development activities for THB335 through the first half of 2025, preparing for a 12-week, placebo-controlled Phase 2 study in CSU by mid-2025 [9] - Ongoing activities include completing subchronic toxicology studies and submitting regulatory filings for Phase 2 initiation [9] Corporate Strategy - In parallel with THB335 Phase 2 readiness, the company is exploring strategic transactions and business combinations to enhance shareholder value, engaging TD Cowen for advisory support [10] - The company is halting all non-THB335 related research and reducing its workforce by approximately 50% [10] Financial Position - As of December 31, 2024, the company reported approximately $285 million in cash and cash equivalents, with an estimated range of $262 million to $267 million expected by June 30, 2025, after accounting for various expenses [11]