US FDA okays COVID booster dose for those with weak immune system

The US Food and Drug Administration (FDA) authorised both the Pfizer-BioNTech and Moderna's Covid-19 vaccine to administer an additional dose in people with weaker immune systems, which includes organ transplant recipients.

The third dose will be administered at least 28 days following the two-dose regimen of the same vaccine to individuals 18 years of age or older (ages 12 or older for Pfizer-BioNTech) who have undergone solid organ transplantation, or who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise, the agency said in a statement on Thursday.

People with organ transplantation and those immunocompromised in a similar manner have a reduced ability to fight infections and other diseases, and they are especially vulnerable to infections, including COVID-19.

The roll out of booster dose is based on FDA's evaluation in these individuals, according to which the administration of third vaccine doses may increase protection in this population.

"The country has entered yet another wave of the COVID-19 pandemic, and the FDA is especially cognizant that immunocompromised people are particularly at risk for severe disease. After a thorough review of the available data, the FDA determined that this small, vulnerable group may benefit from a third dose of the Pfizer-BioNTech or Moderna Vaccines," said Janet Woodcock, Acting FDA Commissioner, in the statement.

"Today's action allows doctors to boost immunity in certain immunocompromised individuals who need extra protection from COVID-19. As we've previously stated, other individuals who are fully vaccinated are adequately protected and do not need an additional dose of COVID-19 vaccine at this time. The FDA is actively engaged in a science-based, rigorous process with our federal partners to consider whether an additional dose may be needed in the future," she added.

These patients should be counseled to maintain physical precautions to help prevent COVID-19. In addition, close contacts of immunocompromised persons should get vaccinated, as appropriate for their health status, to provide increased protection to their loved ones, the FDA said.

The US Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices is scheduled to meet on Friday to discuss further clinical recommendations regarding immunocompromised individuals.

The two-shot COVID-19 vaccine developed by Pfizer-BioNTech is currently authorised for emergency use in individuals ages 12 and older and is administered three weeks apart, while the Moderna shots are authorised for emergency use in individuals ages 18 and older, administered one month apart.