Rheumatoid arthritis flare up; Blood pressure high; Wearing off effect; This spontaneous case was reported by a consumer and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) in a male patient of an unknown age who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product ADALIMUMAB (HUMIRA) for Rheumatoid arthritis.    No medical history was provided by the reporter.  Concomitant products included METHOTREXATE for an unknown indication.   On an unknown date, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form On an unknown date, received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. and ADALIMUMAB (HUMIRA) (Subcutaneous) Citrate Free. On an unknown date, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) (seriousness criterion medically significant), HYPERTENSION (Blood pressure high) and THERAPEUTIC RESPONSE SHORTENED (Wearing off effect). The patient was treated with ASPIRIN [ACETYLSALICYLIC ACID] at an unspecified dose and frequency and RIVAROXABAN (XARELTO) at an unspecified dose and frequency. At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) and THERAPEUTIC RESPONSE SHORTENED (Wearing off effect) had not resolved and HYPERTENSION (Blood pressure high) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood pressure measurement: High.         On Aug-2022, methotrexate was started as concomitant medication. On an unknown date, the patient experienced rheumatoid arthritis flare ups about three days before next Humira injection and blood pressure was very high. It was unknown if patient was enrolled in a COVID-19 Vaccine Trial. Company comment: This spontaneous case concerns a male patient of unknown age with medical history of Rheumatoid arthritis, who experienced the unexpected, serious (Medically significant) AESI of Rheumatoid arthritis. The exact date of administration of an unknown dose of mRNA-1273 and onset of the event was not specified, hence latency could not be assessed. It has been reported that the patient experienced rheumatoid arthritis flare-ups which lasted for three days accompanied by elevated blood pressure. Details of clinical course and treatment were not provided. The event has not resolved at the time of the report. The patient's medical history of Rheumatoid arthritis could be a confounder to the event. The benefit-risk relationship of mRNA-1273 is not affected by this report. Events' seriousness assessed as per medical judgment.; Sender's Comments: This spontaneous case concerns a male patient of unknown age with medical history of Rheumatoid arthritis, who experienced the unexpected, serious (Medically significant) AESI of Rheumatoid arthritis. The exact date of administration of an unknown dose of mRNA-1273 and onset of the event was not specified, hence latency could not be assessed. It has been reported that the patient experienced rheumatoid arthritis flare-ups which lasted for three days accompanied by elevated blood pressure. Details of clinical course and treatment were not provided. The event has not resolved at the time of the report. The patient's medical history of Rheumatoid arthritis could be a confounder to the event. The benefit-risk relationship of mRNA-1273 is not affected by this report. Events' seriousness assessed as per medical judgment.