Immatics announces presentation of data from ongoing Phase 1b trial on IMA203

Immatics (IMTX) announced the presentation of expanded data from the ongoing Phase 1b clinical trial evaluating IMA203 PRAME cell therapy in heavily pretreated patients with metastatic melanoma. The longer follow-up of patients demonstrates a consistent and favorable tolerability profile as well as durable responses with a confirmed ORR of 56%. In addition, the Company provided details from a Trial in Progress poster on SUPRAME, the ongoing Phase 3 clinical trial evaluating IMA203 in patients with unresectable or metastatic cutaneous melanoma who have received prior treatment with a checkpoint inhibitor. The most frequent treatment-emergent adverse events were anticipated cytopenias associated with lymphodepletion. Expected and manageable cytokine release syndrome was mostly Grades 1 and 2, which is consistent with the mechanism of action. The expected median PFS in this post-checkpoint inhibitor patient population6 is 2-3 months, and the IMA203 Phase 1b data presented today at ASCO indicate a continued median PFS of greater than or equal to 6 months.