This spontaneous case was reported by a consumer and describes the occurrence of MYASTHENIA GRAVIS (Generalized myasthenia gravis exacerbated) in a 74-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 001C21A, 036821A and 014M20A) for COVID-19 vaccination. Concurrent medical conditions included Ocular myasthenia (about finishing her treatment for ocular myasthenia.). On 18-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 13-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 17-Aug-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. In 2021, the patient experienced MYASTHENIA GRAVIS (Generalized myasthenia gravis exacerbated) (seriousness criteria hospitalization and medically significant). At the time of the report, MYASTHENIA GRAVIS (Generalized myasthenia gravis exacerbated) had not resolved. Medical Hx: Hx relating to mentioned AE and both Acute and Chronic illnesses at the time of vaccination. Allergies were not provided. The patient did not have COVID + test or diagnosis. No concomitant medication were given. Height- 5'4''.  It was reported that within three weeks of getting the 1st dose of the Moderna COVID 19 vaccine patient got generalized myasthenia gravis and It was then exacerbated after the 2nd and 3rd shot of the vaccine. Patient's doctors said they did not have an idea if the symptoms were related to the vaccine. The online reading suggested it might be due to the mRNA. Patient had been hospitalized for it. Patient got monthly infusion of IVIG at a cost of $12000 per month. Patient was assuming this was how it's going to be for the rest of the life. The patient received urgent care. Treatment medication included monthly infusion of IVIG. Company Comment: This spontaneous case concerns a 74-year-old, female patient with concurrent Ocular myasthenia, who experienced the unexpected, serious (Hospitalized, medically significant) AESI Myasthenia gravis (reported as Generalized myasthenia gravis exacerbated). The event occurred on an unspecified date after the third dose of mRNA-1273. The patient reported occurrence of generalized myasthenia gravis after the first dose with further exacerbation after the second and third doses. The event status was not provided in between doses to assume a positive rechallenge. Clinical course during hospitalization was not provided in the case although it was mentioned that the patient is being treated with monthly IVIg infusion. The patient's concurrent condition, given the usually progressive nature of the disease, remains a confounder. The benefit-risk relationship of mRNA-1273 is not affected by this report. This case was linked to MOD-2022-529242 (Patient Link).; Sender's Comments: This spontaneous case concerns a 74-year-old, female patient with concurrent Ocular myasthenia, who experienced the unexpected, serious (Hospitalized, medically significant) AESI Myasthenia gravis (reported as Generalized myasthenia gravis exacerbated). The event occurred on an unspecified date after the third dose of mRNA-1273. The patient reported occurrence of generalized myasthenia gravis after the first dose with further exacerbation after the second and third doses. The event status was not provided in between doses to assume a positive rechallenge. Clinical course during hospitalization was not provided in the case although it was mentioned that the patient is being treated with monthly IVIg infusion. The patient's concurrent condition, given the usually progressive nature of the disease, remains a confounder. The benefit-risk relationship of mRNA-1273 is not affected by this report.