Researchers are working at a record pace to find ways to treat the virus, primarily through antivirals, and to boost the immune system to prevent people from contracting it in the first place. Thousands of clinical trials of various therapies are taking place around the world, some of which are promising, says pharmacist James Ragotzkie.
Antivirals reduce the ability of the virus to replicate itself. Most antiviral therapies that researchers are testing with COVID-19 patients already have been effective and approved for use in treating other diseases. For example, remdesivir was created for use against hepatitis B and has also been tested for use against Ebola. While some studies have been inconclusive, other studies have shown remdesivir to shorten the time to recovery in some COVID-19 patients. Studies of remdesivir are continuing, says James Ragotzkie.
Another antiviral, hydroxychloroquine, initially looked promising. However, more intensive studies showed no benefit and, occasional harm, to COVID-19 patients on whom doctors used hydroxychloroquine. The FDA has withdrawn its authorization for emergency use of hydroxychloroquine, which was initially created to fight malaria, James Ragotzkie says.
Antibodies are proteins made by plasma cells in the blood that signal the immune system to begin working. Convalescent plasma therapy uses antibodies from patients who have recovered from COVID to treat a current patient. One study in China showed that patients that doctors treated with convalescent plasma recovered more quickly, but scientists must do more extensive research to be sure, says James Ragotzkie.
Monoclonal antibody therapies are produced by isolating the most potent antibodies from a recovered patient. Scientists are studying these therapies as a way to treat patients with the virus. Researchers also are conducting two late-stage clinical trials of monoclonal antibody therapies as a way to prevent people from contracting it at all, says James Ragotzkie.
Two vaccine candidates in late-stage clinical trials use the messenger RNA delivery platform to encode a stabilized SARS-CoV-2 spike immunogen. SARS-COV-2 is the virus that causes COVID-19, and the spike protein facilitates its entry into the cells, says James Ragotzkie. Two other vaccine candidates use adenoviruses, which cause the common cold. Another vaccine candidate uses the modified vesicular stomatitis virus to deliver the instructions for the SARS-CoV-2 protein into cells. Modified vesicular stomatitis is a virus affecting livestock. This delivery system has worked well for building immunity to Ebola, says James Ragotzkie.