Rheumatoid arthritis flare up; Patient had received 2-dose primary series of mRNA-1273 vaccine given at an interval of 24 days; body aches; COVID shots sore arm; Fever; Headache; This spontaneous case was reported by a consumer and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) in a 48-year-old male 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 product included non-company product ADALIMUMAB (HUMIRA) for Rheumatoid arthritis.    Concurrent medical conditions included Rheumatoid arthritis ("MODERATE TO SEVERE RHEUMATOID ARTHRITIS).   On 27-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 23-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient started ADALIMUMAB (HUMIRA) (Subcutaneous). On 23-Mar-2021, the patient experienced INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (Patient had received 2-dose primary series of mRNA-1273 vaccine given at an interval of 24 days). In 2021, the patient experienced PAIN (body aches), VACCINATION SITE PAIN (COVID shots sore arm), PYREXIA (Fever) and HEADACHE (Headache). On an unknown date, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up) (seriousness criterion medically significant). At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis flare up), PAIN (body aches), VACCINATION SITE PAIN (COVID shots sore arm), PYREXIA (Fever), HEADACHE (Headache) and INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (Patient had received 2-dose primary series of mRNA-1273 vaccine given at an interval of 24 days) outcome was unknown. It was unknown if patient was enrolled in a COVID-19 Vaccine Trial. No concomitant product reported by reporter. No treatment medication reported by reporter.  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 is a spontaneous case, reported by a consumer, concerning a 48-year-old male patient with relevant medical condition of moderate to severe Rheumatoid arthritis, who experienced the unexpected serious (medically significant) adverse event of special interest Rheumatoid arthritis, reported as rheumatoid arthritis flare up, in the context of a 2-dose primary series of mRNA-1273 vaccine. Latency cannot be properly assessed since the event onset date was not provided. Patient had received 2-dose primary series of mRNA-1273 vaccine given at an interval of 24 days which did not fall within the recommended vaccine dosing schedule (Inappropriate schedule of vaccine administered). The patient also experienced vaccination site pain, fever, body aches, and headache. No further details about the clinical course, diagnostic procedures and treatments were provided. Outcome of the events were unknown. The medical condition of moderate to severe Rheumatoid arthritis remains as a confounder for the Rheumatoid arthritis flare up. The benefit-risk relationship of mRNA-1273 is not affected by this report. Sender's Comments: This is a spontaneous case, reported by a consumer, concerning a 48-year-old male patient with relevant medical condition of moderate to severe Rheumatoid arthritis, who experienced the unexpected serious (medically significant) adverse event of special interest Rheumatoid arthritis, reported as rheumatoid arthritis flare up, in the context of a 2-dose primary series of mRNA-1273 vaccine. Latency cannot be properly assessed since the event onset date was not provided. Patient had received 2-dose primary series of mRNA-1273 vaccine given at an interval of 24 days which did not fall within the recommended vaccine dosing schedule (Inappropriate schedule of vaccine administered). The patient also experienced vaccination site pain, fever, body aches, and headache. No further details about the clinical course, diagnostic procedures and treatments were provided. Outcome of the events were unknown. The medical condition of moderate to severe Rheumatoid arthritis remains as a confounder for the Rheumatoid arthritis flare up. The benefit-risk relationship of mRNA-1273 is not affected by this report.