Immunocompromised/HCP unsure how long patient has been immunocompromised; This spontaneous case was reported by a pharmacist and describes the occurrence of IMMUNODEFICIENCY (Immunocompromised/HCP unsure how long patient has been immunocompromised) in an 80-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 058F21A, 026A21A and 039K20A) for COVID-19 vaccination.     Concurrent medical conditions included Sulfonamide allergy, Drug allergy (morphine), Drug allergy (Cephalexin), Drug allergy (Cefuroxime), Arthritis and Allergy. Concomitant products included METHOTREXATE and INFLIXIMAB (REMICADE) for an unknown indication.   On 06-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) .5 milliliter. On 06-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to .5 milliliter. On 08-Nov-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to .25 milliliter. On an unknown date, the patient experienced IMMUNODEFICIENCY (Immunocompromised/HCP unsure how long patient has been immunocompromised) (seriousness criterion medically significant). At the time of the report, IMMUNODEFICIENCY (Immunocompromised/HCP unsure how long patient has been immunocompromised) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   No treatment details were reported.  Patient went to the arthritis and allergy clinic. Company comment-This spontaneous case of an elderly female patient aged 80 years with relevant medical history of arthritis and multiple allergy reported, who experienced the unexpected serious (medically significant) event of Immunodeficiency (Immunocompromised) at an unknown interval after third dose of mRNA-1273 vaccine administration. The concomitant medications Methotrexate and Remicade used for unknown indication could be possible confounders to the event. It was reported that patient received 2 doses of the moderna and a booster dose that was half dose. patient was started on Remicade infusions and patient's primary care provider advised patient to get a 4th dose that is full dose. The exact start date of immunocompromised condition of the patient was not known. No clinical or treatment details were given. The outcome of the event was not known at the time of report. The benefit-risk relationship of mRNA-1273 (Moderna covid-19 vaccine) is not affected by this report; Sender's Comments: This spontaneous case of an elderly female patient aged 80 years with relevant medical history of arthritis and multiple allergy reported, who experienced the unexpected serious (medically significant) event of Immunodeficiency (Immunocompromised) at an unknown interval after third dose of mRNA-1273 vaccine administration. The concomitant medications Methotrexate and Remicade used for unknown indication could be possible confounders to the event. It was reported that patient received 2 doses of the moderna and a booster dose that was half dose. patient was started on Remicade infusions and patient's primary care provider advised patient to get a 4th dose that is full dose. The exact start date of immunocompromised condition of the patient was not known. No clinical or treatment details were given. The outcome of the event was not known at the time of report. The benefit-risk relationship of mRNA-1273 (Moderna covid-19 vaccine) is not affected by this report.