Medicenna Therapeutics Corp. (TSX: MDNA, OTCQX: MDNAF), a clinical-stage immunotherapy company, recently provided a significant update on its Phase 1/2 ABILITY-1 study, showcasing promising results from its investigational drug MDNA11 in combination with Merck’s KEYTRUDA® (pembrolizumab). This combination therapy has demonstrated remarkable efficacy in patients with advanced cancer types that have historically shown low responsiveness to immunotherapy.
The highlight of the recent clinical data is the achievement of a complete response (CR) in a 70-year-old male patient suffering from advanced, chemo-refractory anal squamous cell carcinoma (anal SCC). This patient experienced a 100% reduction in all measurable tumors within just eight weeks of treatment with MDNA11 and KEYTRUDA®. Notably, this patient had previously undergone two lines of treatment, including chemotherapy and chemoradiation, without success. The rapid and complete tumor regression underscores MDNA11’s potential to enhance the efficacy of checkpoint inhibitors in challenging cancer types.
In addition to this milestone, the study has reported sustained responses among patients previously resistant to immune checkpoint inhibitors (ICIs). For instance, a patient with melanoma has remained tumor-free for 63 weeks, while another patient with pancreatic cancer has been off all anti-cancer therapies for 11 months after completing the study. These results illustrate the durability of responses seen with MDNA11.
The ABILITY-1 study has shown encouraging disease control rates (DCR) across both monotherapy and combination arms. In the combination arm, which includes nine evaluable patients, the DCR was an impressive 78%, consisting of one CR and one partial response (PR), alongside five stable disease (SD) outcomes. Conversely, the monotherapy arm demonstrated a DCR of 55%, featuring one CR and four PRs among ten patients.
Fahar Merchant, PhD, President and CEO of Medicenna, emphasized the transformative potential of MDNA11 as a combination therapy with KEYTRUDA®, particularly in cancers that have not responded well to existing treatments. He stated, “Achieving a complete response in a patient with anal SCC… demonstrates MDNA11’s ability to reinvigorate the immune system and tackle difficult-to-treat tumors.”
The safety profile of MDNA11 appears favorable, with over 90% of treatment-related adverse events classified as Grade 1-2 and transient. Importantly, no dose-limiting toxicities or new safety signals were observed during the dose escalation cohorts.
As Medicenna progresses with the ABILITY-1 study, additional clinical data will be shared at upcoming medical conferences in Q1 and Q2 of 2025. These presentations will likely provide further insights into both monotherapy and combination treatment outcomes.
MDNA11 is an innovative IL-2 Superkine designed to preferentially activate immune effector cells while minimizing stimulation of immunosuppressive Tregs. This unique mechanism is expected to enhance anti-tumor responses significantly. The ongoing research aims to solidify MDNA11’s role as a potent and safe immunotherapy option for patients battling advanced solid tumors.
The preliminary results from Medicenna’s ABILITY-1 study represent a significant advancement in cancer treatment, particularly for patients facing limited options due to prior treatment failures. With its promising efficacy and favorable safety profile, MDNA11 could redefine therapeutic strategies for challenging cancers like anal SCC and others resistant to current immunotherapies.
