Medicenna Therapeutics provides update on Phase 1/2 ABILITY study

Medicenna Therapeutics announced updated data from its Phase 1/2 ABILITY study of MDNA11, a next-generation IL-2 with superior CD122 binding without CD25 affinity thereby preferentially stimulating cancer killing effector T cells and NK cells. These data include the most recent anti-tumor activity data from the trial’s first four dose escalation cohorts and initial pharmacokinetic/pharmacodynamic data from the fifth dose escalation cohort. Initial PD data from ABILITY’s fifth dose escalation cohort were consistent with the encouraging findings from the first four cohorts. MDNA11 continued to exhibit prolonged, selective, and dose-dependent effects on anti-cancer immunity. Results showed MDNA11 stimulating the proliferation and activation of anti-cancer CD8+ T cells but not regulatory T cells, which are associated with pro-tumor immune pathways. As previously reported, tumor control was achieved in five of fourteen evaluable participants in ABILITY’s first four dose escalation cohorts. Participants in these cohorts failed up to four lines of systemic therapy prior to enrolling in the trial, including eleven who relapsed on, could not tolerate, or did not respond to at least one prior immunotherapy with a checkpoint inhibitor. Participant with 4L metastatic PDAC: Maintained confirmed PR, with both target lesions shrinking by a total of 59% at week 46 from 37% at week 23, relative to baseline. Achieved complete regression of the non-target metastatic lesion. Participant with 3L metastatic melanoma: Maintained SD at week 70 scan and has escalated to a 90 microgram/kg dose of MDNA11. Participant with 3L non-clear cell renal cell carcinoma: Week 23 scan showed progressive disease demonstrating a meaningful period of stable disease prior to progression. Medicenna expects to report initial anti-tumor activity data from ABILITY’s fifth dose escalation cohort at a medical meeting in the second quarter of 2023. Early anti-tumor activity data from ABILITY’s sixth dose escalation cohort and Phase 2 single-agent expansion portion are expected in the third quarter of 2023. Early anti-tumor activity data from ABILITY’s combination arm evaluating MDNA11 plus pembrolizumab are expected in the fourth quarter of 2023.