Washington, Aug 29 (IANS): The US National Institutes of Health (NIH) has begun a clinical trial to assess the antibody response to booster shot of Covid-19 vaccine in people with autoimmune disease who did not respond to the first dose.
The trial also will investigate whether pausing immunosuppressive therapy for autoimmune disease improves the antibody response to an additional dose of a Covid-19 vaccine in such people.
"Many people who have an autoimmune disease that requires immunosuppressive therapy have had a poor immune response to the authorised and approved Covid-19 vaccines, placing these individuals at high risk for the disease," said Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID), in a statement.
"We are determined to find ways to elicit a protective immune response to the vaccines in this population. This new study is an important step in that direction," Fauci added.
The new NIAID trial, called Covida19 booster vaccine in autoimmune disease nonaresponders, initially will include people with one of five autoimmune diseases: multiple sclerosis, pemphigus, rheumatoid arthritis, systemic lupus erythematosus or systemic sclerosis.
The study team will enroll approximately 600 participants ages 18 years and older at 15 to 20 sites across the country.
Participants must also have had a negative or suboptimal antibody response to two doses of the Moderna's Covid vaccine, two doses of the Pfizer-BioNTech vaccine or one dose of the Johnson & Johnson vaccine, all received prior to enrollment.
Participants also must be taking one of three immunosuppressive therapies: mycophenolate mofetil (MMF) or mycophenolic acid (MPA); methotrexate (MTX); or B cell- depleting drugs.
All participants will receive an extra dose of the same Covid-19 vaccine, then those participants who are taking MMF/MPA or MTX will be assigned at random either to continue taking their immunosuppressive medication without alteration or to pause taking their medication for a short period before and after receiving the extra vaccine dose.
The study mainly aims to determine the proportion of participants who have a significantly better antibody response four weeks after receiving the extra vaccine dose than they did after their original vaccinations.
Study participants will be followed for a total of 13 months. Preliminary results are expected in November 2021, the statement said.
The US Food and Drug Administration recently amended the emergency use authorisations for the Pfizer-BioNTech and Moderna Covid-19 vaccines to allow the administration of an additional dose to solid organ transplant recipients and other people who have an equivalent level of immunocompromise.