Graphic by Ishani Singh.
This past Monday, Johnson & Johnson announced a pause in the coronavirus vaccine clinical trial due to unexplained complications experienced by one of the volunteers. However, experts agree that adverse side-effects, especially in a clinical study this size, are expected.
While the company did not specify the complications experienced by the volunteer, they emphasized the importance of intermissions when evaluating vaccine safety. As of last Tuesday, the company was still investigating whether the volunteer had received the vaccine or a placebo and, consequently, whether the complications were a result of the treatment or merely coincidental.
In its statement, the drugmaker stressed that it was undergoing a study pause, rather than a regulatory hold on the clinical trial. A study pause is a temporary halt in recruitment or dosing initiated by the study sponsor, which is a standard protocol in clinical trials. In contrast, a regulatory hold of a clinical trial is a pause mandated by regulatory health authority, such as the FDA, often due to safety concerns.
Currently, the company is further evaluating the medical information about the incident and will forward its findings to the Data Safety and Monitoring Board for guidance on how to proceed. Regardless of the results, experts maintain that such cautionary pauses are integral in uphold the integrity of a trial, especially in light of increasing political pressure for an accelerated vaccine timeline.
Johnson & Johnson is currently conducting the second coronavirus vaccine trial in Phase 3 to be placed on hold in the US, following the pause of AstraZeneca’s vaccine trial last month.