Most of the COVID-19 vaccines currently being distributed require some form of cold storage. Both Pfizer and Moderna need to be kept at temperatures well below zero while AstraZeneca can be stored in standard refrigerated conditions, around 4 degrees Celsius.
Transporting these products relies on a supply chain of freezers and temperature-controlled shipping methods called the “cold chain”.
The challenge is that in remote or resource-constrained areas of the world, there can be logistical issues that mean there are no reliable methods to keep vaccines at low temperatures.
Researchers around the world are addressing this need and racing to develop ‘warm’ vaccines for COVID-19, that can remain stable without any refrigeration.
Scientists at the Indian Institute of Science and Mynvax have developed a heat tolerant vaccine, which has undergone pre-clinical trials.
Results from pre-clinical vaccine trials in India, published in a peer-reviewed paper, have shown that Mynvax formulations triggered a strong immune response in mice and protected hamsters from the coronavirus, and remained stable at 37°C up to a month and at 100°C for up to 90 minutes.
Evaluation of Mynvax exposed to live SARS-CoV-2 virus
Dr S.S. Vasan, co-author on the peer-reviewed publication, has led a study investigating the effectiveness of antibodies in sera (blood samples) from the vaccinated mice to neutralise the virus.
He exposed the sera to live virus of all current SARS-CoV-2 variants of concern.
Results of the study have shown that all samples studied were capable of consistent and effective neutralisation of the Alpha, Beta, Gamma and Delta SARS-CoV-2 variants.
Results from this study will support selection of the most suitable candidate for planned human clinical trials in India, in late 2021.
The peer-reviewed paper, Immunogenicity and protective efficacy of a highly thermotolerant, trimeric SARS-CoV-2 receptor binding domain derivative, was published by ACS Infectious Diseases on 15 July 2021.