Each week, OMRF President Dr. Stephen Prescott opens “Adam’s Journal” to answer a medical question from OMRF Senior Vice President and General Counsel Adam Cohen.
Last week, the drug company AstraZeneca halted its SARS-CoV-2 vaccine trial. What happened? And what does this mean for this and other potential coronavirus vaccines?
Dr. Prescott Prescribes
AstraZeneca suspended clinical testing of its experimental vaccine after a participant experienced what’s known in clinical trials as a serious adverse event. At this time, it’s not known if that event was related to the vaccine.
From reports, it appears the person experienced symptoms consistent with a neurological syndrome called transverse myelitis, or inflammation of the spinal cord. It’s a rare phenomenon, striking about 1,400 people a year in the U.S., according to the National Institutes of Health. It can trigger back pain, muscle weakness and bladder problems.
The causes of transverse myelitis are murky, although scientists believe it’s a byproduct of the body’s inflammatory response run amok, sometimes in response to infection.
In clinical trials, it’s not uncommon for a participant to experience an adverse event. Indeed, at the Oklahoma Medical Research Foundation, where we routinely test new medications for multiple sclerosis, lupus and other diseases, patients in these trials — either at OMRF or another participating site — sometimes experience adverse events.
In those cases, an independent safety monitoring board examines the case to determine whether the event was related to an experimental medication. And that’s precisely what’s happening with the AstraZeneca vaccine trial.
There, more than 10,000 people have received the experimental SARS-CoV-2 vaccine. With so many trial participants, you can see: (1) relatively rare side effects not previously detected in earlier testing with fewer people; and (2) unrelated medical events. The safety monitoring board will now try to determine what category this event fits into.
In the meantime, the fact that AstraZeneca paused this trial shows the system working precisely as it should, with vigilant monitoring and attention to participant safety. And even if this event is ultimately linked to the vaccine, the trial may eventually proceed, especially if the situation appears to be an outlier.
In the world of clinical trials, pauses like this are part of the process. Meanwhile, other coronavirus vaccine trials, which are using vaccines and scientific approaches different than AstraZeneca’s, can continue.