question: We appreciate the letter by Mortezavi et. al. describing vaccine response and the frequency of disease worsening in patients receiving tofacitinib. The ACR COVID Vaccine Guidance Task Force was aware of the two studies cited and appreciate their summary of the results. We would point out that in the rheumatoid arthritis study by Winthrop et. al., patients receiving tofacitinib in Study A had a lower likelihood of a satisfactory response to pneumococcal vaccination (45.1%) compared to placebo‐treated patients (68.4%), a difference of 23.3%, 95% CI −36.6 to −9.6%. The differences were numerically even larger for patients receiving concomitant tofacitinib and methotrexate (31.6% of patients with a satisfactory response, difference of −30.2%, 95% CI −47.3 to −11.4%) compared to methotrexate monotherapy.