Medicenna Completes MDNA11 Dose Escalation and Commences Monotherapy Dose Expansion in the Phase 1/2 ABILITY Study

- Durable anti-cancer activity was observed during monotherapy dose escalation without dose-limiting toxicities

- Late-stage pancreatic cancer patient achieved 80% tumor shrinkage with complete regression observed in two of three metastatic lesions in the liver in response to single-agent MDNA11

- Immune pharmacodynamic data continues to support a differentiated mechanism with preferential expansion of potent cancer-fighting immune cells

- The monotherapy Recommended Dose for Expansion was established at 90g/kg administered every 2 weeks

TORONTO and HOUSTON, Aug. 09, 2023 (GLOBE NEWSWIRE) -- Medicenna Therapeutics Corp. (“Medicenna” or “the Company”) (NASDAQ: MDNA TSX: MDNA), a clinical-stage immunotherapy company, today announced a clinical update on the monotherapy dose escalation portion of the first-in-human, Phase 1/2 ABILITY Study in patients with advanced solid tumors, as its drug candidate MDNA11, a beta-only, long-acting IL-2 super-agonist, advances to the monotherapy dose expansion phase.

“We are pleased to see that MDNA11 continues to demonstrate durable single-agent activity in patients with advanced, treatment-refractory cancer, together with a manageable safety profile, and preserving its differentiated pharmacodynamic (PD) qualities, even though the Phase 1 ABILITY Study was not specifically designed to demonstrate efficacy,” said Fahar Merchant, Ph.D., President and CEO of Medicenna. “The promising therapeutic activity observed in patients who have progressed on multiple prior anti-cancer therapies, including a patient with a particularly aggressive form of cancer – pancreatic ductal adenocarcinoma - fuels our enthusiasm for initiating the dose expansion phase of the study. The PD data supports 90g/kg dose as the Recommended Dose for Expansion (RDE), which will be evaluated in selected cancers that are most likely to benefit from MDNA11 monotherapy. We look forward to the upcoming readouts from the monotherapy dose expansion phase later this year and commencing the combination portion of the trial, where MDNA11 will be evaluated with KEYTRUDA, as part of our clinical collaboration with Merck.”

The main objectives of the dose escalation stage of the Phase 1/2 ABILITY study were to evaluate MDNA11’s safety, tolerability, pharmacokinetics and pharmacodynamics (PK/PD), and preliminary anti-tumor activity to inform RDE selection in patients with advanced cancers that were refractory to up to 4 different lines of systemic therapy. A total of six dose escalation cohorts (MDNA11 dose ranging from 3g/Kg to 120 g/Kg) constituting 20 patients were evaluated, with the majority (75%) having also received at least one line of immunotherapy.