This spontaneous case was reported by a patient and describes the occurrence of SEIZURE (Patient also had a Seizure in Sep 2021) in a 73-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 037c21a and 030b21a) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below. Patient had no history of myocarditis/pericarditis. Concurrent medical conditions included Allergy to nuts (tree nuts). On 18-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 15-Jun-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 15-Jun-2021, after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (1st dose April 18 2021 lot #030b21a/ 2nd dose Jun 15 2021 lot #037c21a). In September 2021, the patient experienced SEIZURE (Patient also had a Seizure in Sep 2021) (seriousness criterion medically significant). At the time of the report, SEIZURE (Patient also had a Seizure in Sep 2021) and INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION (1st dose April 18 2021 lot #030b21a/ 2nd dose Jun 15 2021 lot #037c21a) outcome was unknown. For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments. Concomitant medication reported as patient was taking medication for blood pressure and cholesterol. It was reported as no other vaccines given within 1 month prior to Moderna COVID-19 vaccine. Patient had not experienced a similar event in the past. Patient had not experienced symptoms like this before receiving the Moderna COVID-19 vaccine. Company comment: This Spontaneous case concerns a 73-years-old male patient with no relevant medical history reported, who experienced the unexpected serious (medically significant) AESI event of Seizure which occurred in the context of second dose of mRNA-1273 vaccination. Latency cannot be assessed since event onset date was not disclosed. It was reported that Concomitant medication were medication for blood pressure and cholesterol. No additional information is available regarding diagnostic work-up to support the current diagnosis and treatment received. The event outcome was unknown. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event seriousness assessed as per medical judgement. This case was linked to MOD-2022-615770 (Patient Link). Sender's Comments: This Spontaneous case concerns a 73-years-old male patient with no relevant medical history reported,  who experienced the unexpected serious (medically significant) AESI event of Seizure which occurred in the context of second dose of mRNA-1273 vaccination. Latency cannot be assessed since event onset date was not disclosed. It was reported that Concomitant medication were medication for blood pressure and cholesterol. No additional information is available regarding diagnostic work-up to support the current diagnosis and treatment received. The event outcome was unknown. The benefit-risk relationship of mRNA-1273 is not affected by this report. Event seriousness assessed as per medical judgement.