Rheumatoid arthritis; Lack of drug effect; Nodule on extremity; Early morning stiffness; Tiredness; Headache; Pain in arm; This spontaneous case was reported by a physician and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis) in a 65-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 011L20A and 012M20A) 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.    The patient's past medical history included Nodule in January 2019, Smoker (Non Tobacco smoking) and Abstains from alcohol. Concurrent medical conditions included Sulfonamide allergy (The sulfa drug allergy was rash), Peanut allergy (The peanut allergy was rash) and Drug allergy (The ACE Inhibitors allergy was chest tightness). Concomitant products included DIPHENHYDRAMINE HYDROCHLORIDE (BENADRYL [DIPHENHYDRAMINE HYDROCHLORIDE]) for Allergy, HYDROXYCHLOROQUINE SULFATE (PLAQUENIL [HYDROXYCHLOROQUINE SULFATE]) for Stiffness and Rheumatoid arthritis.   In 2019, the patient started ADALIMUMAB (HUMIRA) (Subcutaneous) 40 mg. On 02-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 40 mg. On 30-Jan-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 40 mg. On 03-Jan-2021, the patient experienced PAIN IN EXTREMITY (Pain in arm). On 30-Jan-2021, the patient experienced FATIGUE (Tiredness) and HEADACHE (Headache). In February 2021, the patient experienced NODULE (Nodule on extremity) and MUSCULOSKELETAL STIFFNESS (Early morning stiffness). On an unknown date, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis) (seriousness criterion medically significant) and DRUG INEFFECTIVE (Lack of drug effect). On 05-Jan-2021, PAIN IN EXTREMITY (Pain in arm) had resolved. On 31-Jan-2021, HEADACHE (Headache) had resolved. On 01-Feb-2021, FATIGUE (Tiredness) had resolved. At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis) outcome was unknown, NODULE (Nodule on extremity) and MUSCULOSKELETAL STIFFNESS (Early morning stiffness) had not resolved and DRUG INEFFECTIVE (Lack of drug effect) had resolved.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered PAIN IN EXTREMITY (Pain in arm), FATIGUE (Tiredness) and HEADACHE (Headache) to be probably related and NODULE (Nodule on extremity) and MUSCULOSKELETAL STIFFNESS (Early morning stiffness) to be not related. No further causality assessments were provided for RHEUMATOID ARTHRITIS (Rheumatoid arthritis) and DRUG INEFFECTIVE (Lack of drug effect).    The patient was treated with prednisone and paracetamol. Action taken with mRNA-1273 in response to the events was not applicable. Company comment: Very limited information regarding this events has been provided at this time.  However, this patient's age, gender, and medical history (nodule) remains a confounders. Further information has been requested.; Sender's Comments: Very limited information regarding this events has been provided at this time.  However, this patient's age, gender, and medical history (nodule) remains a confounders. Further information has been requested.