This spontaneous case was reported by a consumer and describes the occurrence of COVID-19 PNEUMONIA (pneumonia due to COVID) in a 69-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis. Co-suspect product included non-company product DUPILUMAB (DUPIXENT) for Atopic dermatitis. The patient's past medical history included Cataract (mild cataract), Macular degeneration, Bloodshot eye, Tension headache, Paresthesia foot, Eye pain, Unspecified disorder of knee joint, Itchy eyes, Dry eyes, Atopic dermatitis, Knee arthropathy and Total knee replacement. In 2019, the patient started DUPILUMAB (DUPIXENT) (Subcutaneous) 300 milligram. On 26-Oct-2019, DUPILUMAB (DUPIXENT) (Subcutaneous) dosage was changed to 600 milligram. On 28-Aug-2021, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 01-Sep-2021, the patient experienced COVID-19 PNEUMONIA (pneumonia due to COVID) (seriousness criteria hospitalization and medically significant). The patient was hospitalized from 11-Sep-2021 to 16-Sep-2021 due to COVID-19 PNEUMONIA. The patient was treated with OXYGEN for Oxygen saturation low, at an unspecified dose and frequency. At the time of the report, COVID-19 PNEUMONIA (pneumonia due to COVID) had not resolved. DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In August 2020, Full blood count: Low vitamin B12. On an unknown date, Oxygen saturation: Decreased. The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown. Concomitant products were not provided. Patient had taken different medication like macrogol 400, propylene glycol (Systane) for dry eye, cyanocobalamin (vitamin B12) for paraesthesia and vitamin B12 for vitamin B12 decreased and was having an inpatient hospitalized surgery for a total knee replacement for arthropathy and not reported for rest of the events. Oxygen saturation decreased was the symptom of COVID-19 pneumonia. 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 a 69-year-old, female patient who experienced an unexpected, medically significant AESI COVID-19 pneumonia 4 days after receiving a dose of mRNA-1273 vaccine. Patient was hospitalized due to COVID-19 after 2 weeks from vaccination. Oxygen support was given for her desaturation. Medical history included paraesthesia due to a low vitamin B12 level in her complete blood count test, ophthalmologic conditions, and atopic dermatitis treated with dupilumab. Vaccination history included one dose of mRNA-1273 vaccine. Her condition of low vitamin B12 could be a contributory factor to the severity of COVID-19 pneumonia. Dupilumab remains a confounder in this case. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event's seriousness assessed based on medical judgement and the available information. Sender's Comments: This spontaneous case concerns a 69-year-old, female patient who experienced an unexpected, medically significant AESI COVID-19 pneumonia 4 days after receiving a dose of mRNA-1273 vaccine. Patient was hospitalized due to COVID-19 after 2 weeks from vaccination. Oxygen support was given for her desaturation. Medical history included paraesthesia due to a low vitamin B12 level in her complete blood count test, ophthalmologic conditions, and atopic dermatitis treated with dupilumab. Vaccination history included one dose of mRNA-1273 vaccine. Her condition of low vitamin B12 could be a contributory factor to the severity of COVID-19 pneumonia. Dupilumab remains a confounder in this case. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event's seriousness assessed based on medical judgement and the available information.