tested positive for Covid; Sore arm; This is a spontaneous report from a contactable consumer (the patient) received from medical information team. A 74-years-old female patient received first dose of bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Formulation: Solution for injection reported as suspension, Batch/Lot Number: EN6203; Expiration Date: 30Jun2021), via intramuscularly in left arm, on 24Feb2021 16:05 (at the age of 74-years-old) as a single dose for covid-19 immunisation. There were no relevant medical history and concomitant medications. The patient did not receive any prior vaccinations within 4 weeks. On 24Feb2021, the patient experienced sore arm. The patient tested positive for COVID on 06Mar2021. The patient was scheduled to receive her second dose on 16Mar2021 and she was Inquiring what the timeline to wait for the second COVID vaccine dose after getting COVID positive. She further reported that she did look at it this way, maybe the first COVID-19 vaccine helped the COVID-19 virus not be as bad as it could have been. The patient did not hospitalized for adverse events. On 06Mar2021, the patient underwent lab tests and procedures which included COVID saliva test: positive. The outcome of event sore arm was recovered on 25Feb2021 where as the outcome of event tested positive for COVID was unknown.  Summary of Investigation: The initial scope of the investigation was limited to the reported finished goods lot. The final scope was expanded to include the reported finished goods lot EN6203, fill lot EN5336, and the formulated drug product lot EN5324. Manufacturing and packaging batch records were reviewed for the reported complaint lot. (Site Name Withheld) QO did not receive photographs or a complaint sample for examination. The complaint was not confirmed. There were no planned or unplanned deviations recorded during the manufacture of the complaint lot and associated manufacturing lots that may have caused a complaint of this nature. A review of the manufacturing records confirmed processing steps were performed within pre-established parameters. All raw materials and amounts used in the manufacture of the batch were of the correct weight and identity. The drug product is stored at controlled refrigeration throughout the manufacturing process and a log is maintained documenting the elapsed time out of refrigeration. A review of the logs confirmed that all times were within allowable limits. The product also requires storage in ultra-low temperature freezers following the packaging of the product. A review of the freezer temperature log for the reported batch confirmed that all freezer temperatures were within allowable limits. The results of all analytical tests performed at the time of lot release confirmed that the batch continues to meet potency specifications. Conclusion: The complaint for lack of effect of the PFIZER-BIONTECH COVID-19 VACCINE lot EN6203 was investigated. The investigation included a review of manufacturing and packaging batch records, deviation investigations, and an analysis of complaint history for the reported lot. and product type. The final scope included the reported finished goods lot EN6203, fill lot EN5336, and the formulated drug product lot EN5324. A complaint sample was not returned. No related quality issues were identified during the investigation. There is no impact to product quality. No root cause or corrective/preventative actions were identified as the complaint was not confirmed. All release testing performed prior to the release of the reported batch was within specifications.