Turnstone Biologics Corp. Reports Positive Initial Data from Phase 1 Trial of TIDAL-01 in Metastatic Colorectal Cancer

Core Insights - Turnstone Biologics reported positive initial data from its Phase 1 STARLING trial of TIDAL-01 in metastatic microsatellite stable colorectal cancer (MSS mCRC) with an overall response rate (ORR) of 25% and a disease control rate (DCR) of 50% [1][2][3] - The trial demonstrated a complete response in a heavily pre-treated patient with progression-free survival extending beyond one year, indicating the potential for TIDAL-01 to transform treatment paradigms for solid tumors [1][3] - TIDAL-01 showed favorable tolerability and a manufacturing success rate of 80%, with all manufactured products exceeding the target dose of at least 1 billion total T cells [2][3] Clinical Trial Details - The Phase 1 STARLING trial is a multi-site, first-in-human, non-randomized, open-label study evaluating the safety, tolerability, and clinical activity of TIDAL-01 in patients with colorectal cancer, head and neck squamous cell carcinoma, and uveal melanoma [2][4] - As of July 15, 2024, 50% of patients in the trial exhibited sustained clinical benefit, with notable progression-free survival of over one year for the complete response patient and six months for a patient with stable disease [2][3] Product and Technology Overview - TIDAL-01 utilizes an unbiased identification and functional screening process to isolate and expand tumor-reactive TILs, aiming for a higher proportion of functional T cells compared to traditional bulk TIL therapies [4][6] - The manufacturing process for TIDAL-01 has shown consistency and success, with an 80% success rate for generating sufficient starting material for patients [2][3] Market Context - Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths in the United States, with an estimated 153,000 new cases and 53,000 deaths in 2024 [5] - Approximately 85% of CRC patients are classified as microsatellite stable (MSS), which are generally less responsive to existing immunotherapies, highlighting the unmet need for effective treatment options in this patient population [5][6]