The article by the National Institute of Health (NIH) talks about the development process of an investigational vaccine, mRNA-1273, which is being developed to protect people against Covid-19. According to the article, the vaccine is currently undergoing Phase 1 clinical trials. This vaccine has been specifically designed to induce the production of antibodies that can neutralize the “spike protein” at the receptor site that the coronavirus uses to attach and enter human cells. In Phase 1 clinical trials in March 2020, 45 volunteers aged between 18 and 55 years were recruited. The participants were divided into three groups, each having 15 people, before they were given two intramuscular injections of the vaccine with each group receiving a dosage of 25, 100, or 250 mcg. In April, more participants were recruited in the Phase 1 trial, focusing on those aged over 55 years, and it now has 120 participants.
So far, there have not been any reports of serious adverse effects caused by the vaccine. The common issues being reported among participants include pain at the injection point, which is expected, chills, fatigue, myalgia, and headaches. These adverse effects increased after the second injection, and they were more pronounced among those receiving the highest dosage. This information is important as it will play a central role in Phases 2 and 3 clinical trials of the vaccine. Towards the end of May 2020, enrollment for Phase 2 had started, and Phase 3 clinical trial is expected to be launched in July 2020. My questions about this vaccine development include – is the short period taken to conduct Phase 1 clinical trial enough to ascertain how the vaccine works? Is the small number of participants enough to assess the vaccines’ efficacy and safety?
Reference
Experimental COVID-19 vaccine safe, generates immune response. National Institute of Health, 2020. Web.