Some Prescription Drugs May Affect COVID-19 Vaccine Efficacy 

Studies have shown that there is evidence that drugs that suppress the immune system can affect the efficacy of the COVID vaccine. In the US, almost 3% of insured citizens have to take medications that suppress the immune system for diseases such as rheumatoid arthritis, lupus, and chemotherapy for cancer patients. 

Dr. Beth Wallace, rheumatologist at Michigan Medicine, explains that immunosuppressants are used to treat conditions where the body produces an immune response inappropriately, causing the body to attack itself. Immunosuppressants are then used to lower the body’s immune response to provide treatment. Other times when an immunosuppressant may be used is after an organ transplant—this deters the body from recognizing the organ as a foreign body and attacking it. Chemotherapy is a treatment that kills cancer cells and suppresses the immune system as a side effect.  

Another drug which can cause immunosuppression are steroids. Steroids are used for short term conditions like bronchitis, allergic rashes, and sinus infections, with this in mind, the use of immunosuppressants becomes even more common and can affect the efficacy of the vaccine if someone on an immunosuppressant receives it. Dr. Wallace states that “even short courses and low doses of steroids can increase people’s risk of infections, and can reduce their response to vaccines, like the COVID vaccine.”

Immunosuppressive drugs are incredibly useful for treating conditions where the body’s immune response is unregulated, but the mechanism of these drugs reduce the immune system’s ability to recognize a threat and begin the response sequence to provide protection against infection. This suppression is seen with the body’s interaction to vaccines as well and thus causes a slower, weaker immune response in someone who is taking immunosuppressants, and some might not show any response at all. 

Expert accounts suggest that there may be ways to make sure that the immunosuppressed population can still be protected by the vaccine. For those who have flexibility regarding their medication schedules, Dr. Meghan Baker, an epidemiologist who works with immunocompromised patients, states that there can be an adjustment of timing for medication. The recommendation is to complete the vaccine series at least two weeks before beginning the medication. 

For those who do not have flexibility in treatment, it is recommended that the patient work with their provider about the risks versus the benefits of delaying therapy. Dr. Wallace also makes a point to mention that there is not much information on every drug on the market and how each one may affect vaccine response, as well as the crucial difference in pausing treatment for higher risk such as with cancer patients. Booster shots for those in the immunocompromised population have been in speculation. 

Because there is not much information yet on the effectiveness of vaccines in this population and if they are being truly protected, the CDC is recommending that even if they are able to get vaccinated, they should continue to social distance and engage in masking and proper handwashing techniques to ensure that they remain protected.