This spontaneous case was reported by a consumer and describes the occurrence of DIABETES MELLITUS (Diabetic) in an elderly 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 Plaque psoriasis. There were no known allergy. Concurrent medical conditions included Plaque psoriasis. On 11-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 11-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) at an unspecified dose. In 2021, the patient experienced VACCINATION SITE PAIN (HAD COVID SHOT/SORE ARM) and PYREXIA (Feverish). On an unknown date, the patient experienced DIABETES MELLITUS (Diabetic) (seriousness criterion medically significant), TENDON DISORDER (PHYSICIAN THOUGHT MIGHT HAD A MUSCLE OR TENDON ISSUE), MUSCLE DISORDER (PHYSICIAN THOUGHT MIGHT HAD A MUSCLE OR TENDON ISSUE), CHEST PAIN (CHEST PAINS WHEN REACHED FOR SOMETHING), WEIGHT DECREASED (Weight loss) and CHEST DISCOMFORT (CONGESTION/ FEELS TIGHT IN CHEST). At the time of the report, DIABETES MELLITUS (Diabetic) and CHEST DISCOMFORT (CONGESTION/ FEELS TIGHT IN CHEST) was resolving, TENDON DISORDER (PHYSICIAN THOUGHT MIGHT HAD A MUSCLE OR TENDON ISSUE), MUSCLE DISORDER (PHYSICIAN THOUGHT MIGHT HAD A MUSCLE OR TENDON ISSUE), CHEST PAIN (CHEST PAINS WHEN REACHED FOR SOMETHING) and WEIGHT DECREASED (Weight loss) had not resolved and VACCINATION SITE PAIN (HAD COVID SHOT/SORE ARM) and PYREXIA (Feverish) outcome was unknown. DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Cardiac stress test: All ok. On an unknown date, Glycosylated haemoglobin: Borderline diabetic and dropped down to 6.1. On an unknown date, Weight: Lost about 23-30 pounds. No concomitant medication was reported. It was unknown if patient was enrolled in a COVID-19 Vaccine Trial. No treatment medication was reported. 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. An elderly male patient in treatment with Adalimumab for plaque psoriasis, completed a two-dose primary series of mRNA-1273 vaccine with an interval of 28 days between doses and experienced medically significant event of diabetes mellitus. Onset date of the event was not provided, latency cannot be assessed. In addition, patient experienced non serious events of vaccination site pain, fever, chest pains when reached for something (physician thought might had a muscle or tendon issue), weight decreased (about 23-30 pounds) and chest tightness. Diagnostic test results performed on an unknown date included: cardiac stress test: normal; A1C test: borderline diabetic and A1C: dropped down to 6.1. No further details regarding clinical course, diagnostic tests or treatment performed were disclosed. Current condition of plaque psoriasis is a risk factor for developing diabetes, also could be a contributory factor for tendon disorder, muscle disorder and chest pain. Adalimumab could be a contributory factor for chest pain. Diabetes mellitus, Weight loss, and Chest tightness were considerer not related to mRNA-1273 per the reporter's assessment. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Sender's Comments: This is a spontaneous case reported by a consumer. An elderly male patient in treatment with Adalimumab for plaque psoriasis, completed a two-dose primary series of mRNA-1273 vaccine with an interval of 28 days between doses and experienced medically significant event of diabetes mellitus. Onset date of the event was not provided, latency cannot be assessed. In addition, patient experienced non serious events of vaccination site pain, fever, chest pains when reached for something (physician thought might had a muscle or tendon issue), weight decreased (about 23-30 pounds) and chest tightness. Diagnostic test results performed on an unknown date included: cardiac stress test: normal; A1C test: borderline diabetic and A1C: dropped down to 6.1. No further details regarding clinical course, diagnostic tests or treatment performed were disclosed. Current condition of plaque psoriasis is a risk factor for developing diabetes, also could be a contributory factor for tendon disorder, muscle disorder and chest pain. Adalimumab could be a contributory factor for chest pain. Diabetes mellitus, Weight loss, and Chest tightness were considerer not related to mRNA-1273 per the reporter's assessment. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.