CONFIRMED CLINICAL VACCINATION FAILURE; CONFIRMED COVID-19 INFECTION; This spontaneous report received from a patient concerned a 66 year old, female. Initial information was processed along with the additional information received on 27-JUL-2022 The patient's height, and weight were not reported. The patient's concurrent conditions included: rheumatoid arthritis, allergy, and immunocompromised. The patient received covid-19 vaccine ad26.cov2.s (dose number in series:1) (suspension for injection, route of admin not reported, batch number: 1808609 expiry: UNKNOWN) dose was not reported, 1 total administered to left arm on 27-MAR-2021 for covid-19 prophylaxis.  Concomitant medications included bupropion hydrochloride for drug used for unknown indication, celecoxib for drug used for unknown indication, diclofenac sodium for drug used for unknown indication, gabapentin for drug used for unknown indication, lisinopril for drug used for unknown indication, omeprazole for drug used for unknown indication, sulfasalazine for drug used for unknown indication, and levothyroxine sodium. On an unspecified date in MAR-2021 after receiving the first dose, the patient experienced horrible taste, Diarrhea, rebound effect, fever (dose number in series: 1). On 13-APR-2021, the patient tested mildly positive (confirmed clinical vaccination failure) and patient experienced symptoms like cough, congestion (confirmed covid-19 infection) (dose number in series: 1). The patient received second dose of Non-company suspect vaccine tozinameran (Pfizer) (dose number in series: 2) (form of admin, route of admin were not reported, batch number: 33030BD expiry: Unknown) dose was not reported, administered on 08-DEC-2021 to left arm for covid-19 prophylaxis. The patient reported he stopped his medications for about a week. The patient was isolated on 15-APR-2022 and he received OTC medications.  The patient received third dose of Non-company suspect vaccine tozinameran (Pfizer) (dose number in series: 2) (form of admin, route of admin were not reported, batch number: PE3594 expiry: Unknown) dose was not reported, administered on 29-DEC-2021 to left arm for covid-19 prophylaxis. The patient received fourth dose of Non-company suspect vaccine tozinameran (Pfizer) (dose number in series: 2) (form of admin, route of admin were not reported, batch number: FJ1614 expiry: Unknown) dose was not reported, administered on 26-JAN-2022 to left arm for covid-19 prophylaxis. It was unknown whether patient had any adverse events following covid-19 vaccine tozinameran (Pfizer) (dose number in series: 2). On 30-JUN-2022, the patient was treated with non-company suspect drug Paxlovid (route of administration, batch number and expiry were not reported) dose and frequency were not reported for covid-19 treatment and last administered on 04-JUL-2022. As patient was immunocompromised, doctor suggested second course of non company suspect drug Paxlovid. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient was recovering from confirmed covid-19 infection, and the outcome of confirmed clinical vaccination failure was not reported. This report was serious (Other Medically Important Condition). This report was associated with a product quality complaint: 90000243898.; Sender's Comments: V0-20220752217-covid-19 vaccine ad26.cov2.s-Confirmed clinical vaccination failure. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s). Therefore, this event(s) is considered unassessable.