This is a literature report for the following literature source(s): Other Case identifier(s): 20220402436 (Janssen). An adult female patient received BNT162b2 (BNT162B2), as dose 3 (booster), single (Batch/Lot number: unknown) for Covid-19 immunisation; Janssen CoviD-19 vaccine (JANSSEN COVID-19 VACCINE), as dose number unknown, single (Batch/Lot number: unknown) for immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Covid-19 vaccine (1st dose), for COVID-19 immunization; Covid-19 vaccine (2nd dose), for COVID-19 immunization. The following information was reported: MYOCARDITIS (medically significant), outcome "unknown", described as "Mild Myocarditis". The event "mild myocarditis" required emergency room visit. The patient underwent the following laboratory tests and procedures: Echocardiogram: 60-65, notes: 60 to 65; Electrocardiogram: 37 elevation positive, notes: 37 elevation positive; Troponin: 0.04 mcg/L, notes: Normal troponin range: <=.03 mcg/L. This report concerned an adult female (Age between 23-24 years). It was unknown whether patient had any adverse events following vaccination with first dose of Covid-19 vaccine ad26, cov2.s (dose number in series 1). The Patient: additionally received non-company suspect vaccine: Pfizer BioNTech Covid-19 Vaccine (Tozinameran, dose number in series 2) (form of admin, route of admin, and hatch number were rot reported) dose, start- therapy dare were not reported for prophylactic vaccination. Interval between prime series to booster was 196 days. On an unspecified date, the patient experienced chest pain after four days of booster. The patient presented with mild myocarditis after heterologous series of JNJ vaccine followed by a booster dose of Pfizer vaccine (dose number in series 2). The authors discussed that Myopericarditis occurs after Booster doses and may be underreported by current surveillance methods. Completeness or high sensitivity of these ease estimates are essential when modeling risk and benefit for wide-scale vaccine implementation and sequential COVID-19 vaccinations for the general population. Company Remarks (Sender's comments) VO: 202204C2436-Covid-19 vaccine ad26. cov2.s-mild myocarditis. 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: CONMEDS-OTHER SUSPECT DRUGS. (Non-company suspect Pfizer vaccine: BioNTech Covid-19 Vaccine). Therefore, this event (s) is considered not related. Causality: Mild Myocarditis (Myocarditis, Myocarditis), Causality as per Mfr. (Drug/Vaccine): Possible, Causality as per reporter (Drug/Vaccine): Possible. No follow-up attempts are possible; information about lot/batch number cannot be obtained. No further information is expected. Sender's Comments: Based on the available information in the case, the causal association between the event myocarditis and the suspect drug cannot be excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.