Interim data from the Phase I dose escalation part of the mRNA cancer immunotherapy (mRNA-4359) show promise in patients with advanced solid cancers, including lung cancer, melanoma, and other solid tumors. The investigational immunotherapy treatment was administered to nineteen patients with advanced stage cancers, with results showing that it created an immune response against cancer and was well tolerated, with adverse events being fatigue, injection site pain, and fever. The Phase I trial, which is sponsored by Moderna, is the first-in-human study of the therapy and is being presented at the European Society of Medical Oncology conference in Barcelona by the UK Chief Investigator from King’s College London and Guy’s and St Thomas’ NHS Foundation Trust.
The mRNA cancer immunotherapy is part of a growing number of cancer vaccines entering clinical trials worldwide, working by presenting common markers of tumors to patients’ immune systems and training them to recognize and fight cancer cells expressing them. The Phase I trial was designed to assess the safety and tolerability of the immunotherapy, with secondary and tertiary objectives focusing on radiographic and immunological responses. Early data from the trial showed that eight out of sixteen patients whose responses were evaluated demonstrated that their tumor size did not grow, and no new tumors appeared. The immunotherapy was found to activate the immune system in many patients, generating immune cells in the blood capable of recognizing specific proteins (PD-L1 and IDO1) of interest.
The study authors caution that the results should be treated with caution due to the small sample size and the primary objective being focused on safety and determining the optimal dose of the immunotherapy. However, these promising early results support further research into mRNA-4359 as a potential treatment for advanced cancers. The trial is ongoing and continues to recruit patients with melanoma and lung cancer in combination with the immunotherapy drug pembrolizumab to gather more data on the safety and efficacy of the therapy. Dr. Debashis Sarker, the UK’s Chief Investigator of the trial and a Clinical Reader in Experimental Oncology at King’s College London, emphasizes the importance of this study as a first step in developing a new treatment for patients with advanced cancers, highlighting the therapy’s tolerability and immune-stimulating properties.
Dr. Sarker acknowledges that while the early results are promising, it is too early to determine the effectiveness of the therapy for advanced stage cancer due to the small number of patients involved in the study. He emphasizes the international collaboration across the UK, USA, Spain, and Australia in recruiting patients for the trial and continuing research efforts into mRNA-4359. Kyle Holen, M.D., Moderna’s Senior Vice President and Head of Development, Therapeutics, and Oncology, expresses encouragement towards the Phase I results of mRNA-4359, noting its potential to elicit strong antigen-specific T-cell responses while maintaining a manageable safety profile. He suggests that this novel approach could play a significant role in shifting the tumor microenvironment towards a more immune-permissive state, offering hope for patients with advanced solid tumors.