Rheumatoid arthritis flare up; Pain/After receiving booster shot patient was in pain; Interchange of vaccine products; Revaccination with different COVID -19 vaccine; This spontaneous case was reported by a consumer and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) in an elderly female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect products included non-company products ADALIMUMAB (HUMIRA) for Rheumatoid arthritis and TOZINAMERAN (PFIZER BIONTECH COVID-19 VACCINE) for COVID-19 vaccination.    Concurrent medical conditions included Rheumatoid arthritis.   On an unknown date, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form, ADALIMUMAB (HUMIRA) (Subcutaneous) UNK, CF and dose of TOZINAMERAN (PFIZER BIONTECH COVID-19 VACCINE) (Intramuscular) 1 dosage form. On an unknown date, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) (seriousness criterion medically significant), PAIN (Pain/After receiving booster shot patient was in pain), INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products) and COVID-19 IMMUNISATION (Revaccination with different COVID -19 vaccine). The patient was treated with BETAMETHASONE at an unspecified dose and frequency. At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) was resolving and PAIN (Pain/After receiving booster shot patient was in pain), INTERCHANGE OF VACCINE PRODUCTS (Interchange of vaccine products) and COVID-19 IMMUNISATION (Revaccination with different COVID -19 vaccine) outcome was unknown.            Formulation for HUMIRA (ADALIMUMAB) was given as solution for injection in pre-filled pen.  After receiving her booster shot patient was in pain with HUMIRA.  The reporter's causality for the event of rheumatoid arthritis with HUMIRA (ADALIMUMAB) was no reasonable possibility. The reporter's causality for the event of pain was not provided.  This case was identified as part of a retrospective clean-up activity where certain emails received in the Moderna mailbox were missed to be booked-in.  Company Comment: This spontaneous case concerns an elderly female patient with relevant medical history of Rheumatoid arthritis and administration of non-company brand COVID-19 vaccine Tozinameran (Pfizer Biontech), who experienced the unexpected, serious  (medically significant) adverse event of special interest Rheumatoid arthritis (Rheumatoid arthritis flare up) on an unknown date in the context of receiving  a dose of mRNA-1273 vaccine.  Onset latency could not be determined as the date of vaccination and the date of event onset were not disclosed. Patient was treated with Betamethasone.  No information on any other doses of COVID-19 vaccination was provided. The administration of non-company brand COVID-19 vaccine Tozinameran (Pfizer Biontech) remains a confounder,  and the relevant medical history of Rheumatoid arthritis as a disease itself is known to result in flares. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This spontaneous case concerns an elderly female patient with relevant medical history of Rheumatoid arthritis and administration of non-company brand COVID-19 vaccine Tozinameran (Pfizer Biontech), who experienced the unexpected, serious  (medically significant) adverse event of special interest Rheumatoid arthritis (Rheumatoid arthritis flare up) on an unknown date in the context of receiving  a dose of mRNA-1273 vaccine.  Onset latency could not be determined as the date of vaccination and the date of event onset were not disclosed. Patient was treated with Betamethasone.  No information on any other doses of COVID-19 vaccination was provided. The administration of non-company brand COVID-19 vaccine Tozinameran (Pfizer Biontech) remains a confounder,  and the relevant medical history of Rheumatoid arthritis as a disease itself is known to result in flares. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.