CONFIRMED CLINICAL VACCINATION FAILURE; CONFIRMED COVID-19 INFECTION; REVACCINATION WITH DIFFERENT COVID-19 VACCINE; This spontaneous report received from a patient via other manufacturer (pfizer) concerned a 63 year old male for unspecified race and ethnic origin. Initial information was processed along with additional information received on 03-MAY-2023. The patient's height, and weight were not reported. The patient's past medical history included: mild TIA (transient ischaemic attack), and concurrent conditions included: coronary arterial spasms, avelox allergy, penicillin allergy and hypertension. The patient received first dose of covid-19 vaccine ad26. cov2. s (dose number in series 1) (suspension for injection, route of admin not reported, batch number: 041A21A expiry: UNKNOWN) dose was not reported, 1 total, administered on 31-MAR-2021 into right arm for covid-19 prophylaxis.  It was unknown whether patient had any adverse events following vaccination with covid-19 vaccine ad26.cov2.s (dose number in series 1). The patient received second dose of covid-19 vaccine ad26.cov2.s (dose number in series 2) (suspension for injection, route of admin not reported, batch number: 1822811 expiry: UNKNOWN) dose was not reported, 1 total, administered on 04-NOV-2021 into left arm for covid-19 prophylaxis. Age at time of vaccination 62 years old. No concomitant medications were reported.  The patient received third dose of non-company suspect vaccine included: elasomeran (dose number in series 3) (batch number: A57143C expiry: UNKNOWN, form of admin and route of admin were not reported) dose was not reported, administered on 08-SEP-2022 into left arm for covid-19 prophylaxis with revaccination with different covid-19 vaccine (dose number in series 3). On an unspecified date in 2023, patient had tested positive for covid which was confirmed covid-19 infection (dose number in series 3) which led to confirmed clinical vaccination failure (dose number in series 2). The patient received non-company suspect drugs included: nirmatrelvir/ritonavir (form of admin, route of admin, and batch number were not reported) dose and frequency were not reported from 11-APR-2023 to 15-APR-2023 for covid-19 treatment.  On 17-APR-2023, patient tested negative. On 21-APR-2023 patient again tested positive with mild symptoms and primary physician placed him on second round of Paxlovid. The patient received non-company suspect drug included: nirmatrelvir/ritonavir (form of admin, route of admin, and batch number were not reported) dose and frequency were not reported from 21-APR-2023 for covid-19 treatment. The action taken with covid-19 vaccine ad26.cov2.s and elasomeran was not applicable, and nirmatrelvir/ritonavir was not reported. The patient was recovering from confirmed covid-19 infection, and the outcome of confirmed clinical vaccination failure and revaccination with different covid-19 vaccine was not reported. This report was serious (Other Medically Important Condition). This report was associated with a product quality complaint: 90000281233; Sender's Comments: V0: 20230504626- confirmed clinical vaccination failure. The event has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event. Specifically: SPECIAL SITUATIONS. Therefore, this event is considered inconsistent with vaccine administration.