CONFIRMED CLINICAL VACCINATION FAILURE; CONFIRMED COVID-19 INFECTION; This spontaneous report received from a patient via other manufacturer (Pfizer) concerned a 52 year old male. Initial information was processed along with additional information received on 28-JUL-2022. The patient's height, and weight were not reported. The patient's concurrent conditions included: high cholesterol/triglycerides, and drug allergy. The patient was previously treated with two doses of Pfizer covid-19 vaccine (tozinameran) (dose number in series 1). The patient received first dose (form of admin and route of admin were not reported and batch number: EN6207 expiry: UNKNOWN) dose was not reported, administered on 16-MAR-2021 for covid-19 prophylaxis. The patient received second dose (form of admin, route of admin was not reported and batch number: ER8729 expiry: UNKNOWN) dose was not reported, administered on 13-APR-2021 for covid-19 prophylaxis.   It was unknown whether patient had any adverse events following vaccination with two doses of Pfizer covid-19 vaccine (tozinameran) (dose number in series 1). The patient received covid-19 vaccine ad26.cov2.s (dose number in series 2) (suspension for injection, route of admin not reported, batch number: 213D21A expiry: UNKNOWN) dose was not reported, 1 total, administered on 15-DEC-2021 for covid-19 prophylaxis. Age at time of vaccination 51 years old.  Concomitant medications included acetylsalicylic acid, brompheniramine, cetirizine hydrochloride, ergocalciferol, ezetimibe, fluticasone propionate, ibuprofen, rosuvastatin, and zinc were used for unknown indication. On an unspecified date in 2022, the patient experienced covid-19 infection (confirmed clinical vaccination failure, and confirmed covid-19 infection) (dose number in series 2). The patient received non company suspect Paxlovid (form of admin, route of admin, and batch number were not reported) dose was not reported, administered from 12-JUL-2022 to 16-JUL-2022 for covid-19 treatment.  The patient reported that symptoms were started again four days after last dose of Paxlovid treatment. Symptoms were mild and included runny nose, sore throat and diarrhoea (dose number in series 2). On 18-JUL-2022, Laboratory data included: COVID-19 rapid antigen test result was fain compared to the control. On 20-JUL-2022, Laboratory data included: COVID-19 rapid antigen test result was as strong as the control (dose number in series 2). The action taken with covid-19 vaccine ad26.cov2.s was not applicable and with paxlovid was drug discontinued. The patient had not recovered 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 product quality complaint.; Sender's Comments: V0: 20220754628- 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 are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS. Therefore, this event(s) is considered not related.