Moderna vaccine expired on 20-May-2022 and was stored in refrigerator on 07-Jun-2022; No adverse Event; Patient received booster dose of expired Moderna COVID-19 vaccine; This spontaneous case was reported by an other health care professional and describes the occurrence of EXPIRED PRODUCT ADMINISTERED (Patient received booster dose of expired Moderna COVID-19 vaccine), PRODUCT STORAGE ERROR (Moderna vaccine expired on 20-May-2022 and was stored in refrigerator on 07-Jun-2022) and NO ADVERSE EVENT (No adverse Event) in an 86-year-old patient of an unknown gender who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 033K21-2A) for COVID-19 vaccination.     No Medical History information was reported.   On 29-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 26-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 07-Dec-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 08-Jun-2022, received fourth dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 08-Jun-2022,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced EXPIRED PRODUCT ADMINISTERED (Patient received booster dose of expired Moderna COVID-19 vaccine). On an unknown date, the patient experienced PRODUCT STORAGE ERROR (Moderna vaccine expired on 20-May-2022 and was stored in refrigerator on 07-Jun-2022) and NO ADVERSE EVENT (No adverse Event). At the time of the report, EXPIRED PRODUCT ADMINISTERED (Patient received booster dose of expired Moderna COVID-19 vaccine), PRODUCT STORAGE ERROR (Moderna vaccine expired on 20-May-2022 and was stored in refrigerator on 07-Jun-2022) and NO ADVERSE EVENT (No adverse Event) outcome was unknown. Not Provided      For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered NO ADVERSE EVENT (No adverse Event) to be not related. No further causality assessments were provided for EXPIRED PRODUCT ADMINISTERED (Patient received booster dose of expired Moderna COVID-19 vaccine) and PRODUCT STORAGE ERROR (Moderna vaccine expired on 20-May-2022 and was stored in refrigerator on 07-Jun-2022).    No concomitant medications were reported.  It was unknown if the patient had ever tested positive for COVID-19, or had any allergy and had any acute illness at the time of vaccination and up to 1 month before and received any vaccine one month prior to moderna covid-19 vaccine. It was unknown if the patient had taken any prescriptions, over the counter medication, dietary supplement or herbal remedies at the time of vaccination and other vaccines given within 1 month prior to Moderna COVID-19 vaccine. It was unknown if the adverse event caused patient to seek medical care (office visit, Urgent care, ER, hospitalized), or the patient experienced a similar event in the past and the symptoms improved or worsened.  It was reported that, the medical assistant thought that the expiration date was 20-Jun-2022 when looked this up before however there was nothing in writing or printed to confirm the expiration date of 20-Jun-2022. Vial was initially stored in refrigerator on 07-Jun-2022. The vial did not undergo temperature excursion. The patient did not experience any adverse events. No treatment medication was reported.   Most recent FOLLOW-UP information incorporated above includes: On 01-Sep-2022: Significant Live follow-up received contains updated suspect details and narrative. On 02-Sep-2022: Live follow-up received contains no new information.