Core Insights - Immatics N.V. announced updated Phase 1a dose escalation data for its second-generation PRAME cell therapy, IMA203CD8, targeting difficult-to-treat solid tumors expressing PRAME, including ovarian cancer [1][3][4] Patient Population - The ongoing Phase 1a trial enrolled 78 heavily pre-treated patients with advanced solid tumors expressing PRAME, with a median of three prior systemic treatments [4] - The efficacy-evaluable population included 69 patients, comprising 42 with melanoma, 11 with ovarian carcinoma, 11 with synovial sarcoma, and 5 with other tumor types [4] Safety Profile - IMA203CD8 demonstrated manageable tolerability, with the most common treatment-emergent adverse events being cytopenias associated with lymphodepletion [5][7] - Cytokine release syndrome (CRS) was mostly Grade 1 to 2, with Grade 1 at 35%, Grade 2 at 50%, Grade 3 at 9%, and Grade 4 at 1% [5] Anti-Tumor Activity - Initial results showed deep and durable objective responses in PRAME-positive advanced solid tumors, with a one-time infusion of IMA203CD8 leading to a 36% confirmed objective response rate (cORR) and a 46% overall response rate (ORR) [10][12] - In patients with ovarian carcinoma, a promising dose-dependent signal was observed, with two confirmed partial responses and one ongoing metabolic complete response at the highest dose level [11] Clinical Development - The company aims to complete the Phase 1a dose escalation and determine the recommended Phase 2 dose (RP2D) by 2026, including data on the two highest dose levels [15] - IMA203CD8 is positioned to target advanced PRAME cancers beyond melanoma, starting with gynecologic cancers, and may not require post-infusion low-dose IL-2 in the future [14][16] Company Overview - Immatics is a leader in precision targeting of PRAME, with a broad franchise that includes multiple product candidates and therapeutic modalities targeting PRAME across various cancers [17][18]