So far, there are no widely-accepted treatments for COVID-19. Hydroxychloroquine, often mixed with other things like azithromycin, was initially thought to be promising, but the data so far are inconclusive. While there are some indications that it is effective (and some physicians are convinced it works very well), the controlled studies that have been done so far see no significant benefit to its use. The antiviral drug remdesivir shows some promise, as does the corticosteroid drug dexamethasone. However, there are not enough data yet to make a firm decision on either of them.
Yesterday, President Trump held a press conference to announce a new possible treatment: convalescent plasma. Based on an analysis of several different studies, it seems to be the best candidate yet (in my non-medical-doctor opinion). I say this because of the kinds of studies that have been done. First, there have been three randomized clinical trials. This means patients were assigned to either get the treatment or not get the treatment based on random chance. The group that got the treatment was compared to the group that didn’t (called the control group). In the three studies, the death rate in the treatment group was half that of the control group. There were also five matched-control studies, where the treated patients were compared to a control group specifically selected to closely match them. The results of those studies were similar to those of the randomized clinical trials. There were also four case-series studies, where patients were given the treatment and their progress was tracked. While that kind of study has practical uses for physicians, its ability to determine the effectiveness of a treatment is extremely limited. However, the case-series studies seem to support the other two kinds of studies. All of the studies were done on patients with severe or life-threatening cases of COVID-19.
Taken all together, then, the treatment looks very promising. However, I do have to say that each study was very small, so even when all the patients were analyzed, the total number was only 804. Phase three clinical trials that determine whether or not a drug should be widely used typically involve a few thousand patients. Thus, this is still a limited data set. Also, many of the studies (as well as the analysis linked above) are not peer-reviewed. As a result, there could be major flaws that have not been noticed. A recent analysis (once again not peer reviewed) of more than 35,000 patients seems to support the small studies, but since it has no control group, it cannot be used to draw any real conclusions. Nevertheless, the FDA has approved emergency use of the treatment, and it is asking those who have recovered from the disease to help in determining whether or not it is truly effective.
How can someone who has recovered from COVID-19 help determine the effectiveness of the treatment? To understand that, you need to learn a bit about the wonderful mixture that is running through your circulatory system.