Medicenna Therapeutics Corp. announced new clinical data from the Phase 1/2 ABILITY (A Beta-only IL-2 ImmunoTherapY) study of MDNA11, the Company's long-acting IL-2 super-agonist. In the ABILITY study, dose escalation cohorts are evaluating MDNA11 monotherapy administered intravenously once every two weeks to patients with advanced solid tumors.

The trial's first two cohorts (n = 4) evaluated MDNA11 doses = 10 µg/kg (IL-2 content of = 2 µg/kg). The trial's third cohort (n = 4) utilized a dose of 30 µg/kg (IL-2 content of 6 µg/kg). Key findings from these initial dose escalation cohorts include: Levels of Ki67+ expression by CD8+ T and NK cells increased 17-fold and 10-fold over baseline, respectively, following treatment with MDNA11 in the trial's third dose escalation cohort.

MDNA11 treatment led to the dose-dependent and significant expansion of CD8+ T and NK cells at the 30 µg/kg when compared to MDNA11 doses of = 10 µg/kg. Levels of each cell type increased >3-fold and >6-fold over baseline, respectively, in the trial's third dose escalation cohort. MDNA11 preferentially increased anti-cancer CD8+ T cells over pro-tumor Treg cells, as the mean peak CD8+ T cell /Treg ratio increased by 2.6 fold over baseline in cohort 3. MDNA11 preferentially increased anti-cancer NK cells over Treg cells, as the mean peak NK cell /Treg ratio increased 4.4-fold over baseline in the trial's third dose-escalation cohort.

MDNA11 continues to exhibit an acceptable safety profile. No dose limiting toxicities have been reported in the ABILITY study to date.