Treatment of COVID-19; Treatment of COVID-19; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from product quality group. The reporter is the patient.  A 75-year-old female patient (not pregnant) received BNT162b2 (BNT162B2), on 25Feb2021 at 17:00 as dose 1, single (Lot number: EN6204), in left arm, on 08Mar2021 as dose 2, single (Lot number: EN6204), in left arm, on 26Oct2021 as dose 3 (booster), single (Lot number: 30155BA), in left arm and on 18Apr2022 at 12:00 as dose 4 (booster), single (Lot number: FM9992) at the age of 75 years, in left arm for covid-19 immunisation. The patient's relevant medical history included: "radiation cystitis" (unspecified if ongoing); "short gut syndrome" (unspecified if ongoing); "bronchyecstasis" (unspecified if ongoing); "chronic anemia" (unspecified if ongoing); "hypothyroid" (unspecified if ongoing); "lymphedema" (unspecified if ongoing); "Known allergies: several antibiotics" (unspecified if ongoing). There were no concomitant medications. Past drug history included: Benadryl, reaction(s): "Known allergies: benadryl"; Thimerasol, reaction(s): "Known allergies: thimerasol". after about 4 days cough and cold symptoms started returning. Fatigue never left after finishing Paxlovid. The following information was reported: VACCINATION FAILURE (medically significant), COVID-19 (medically significant), outcome "unknown" and all described as "Treatment of COVID-19". The patient underwent the following laboratory tests and procedures: SARS-CoV-2 test: Positive, notes: Treatment of COVID-19. Therapeutic measures were taken as a result of vaccination failure, covid-19, which included Paxlovid.  Conclusion: The complaint for lack of effect of the PFIZER-BIONTECH COVID-19 VACCINE lot EN6204 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. The final scope included the reported finished goods lot EN6204, fill lot EN5335, and the formulated drug product lot EN5325. A complaint sample was not returned, and photographs were not received. 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.  The complaint for a lack of effect in a vial of PFIZER-BIONTECH COVID-19 VACCINE was investigated. The investigation included reviewing incoming quality and manufacturing batch records, deviation investigations, an analysis of the complaint history for the reported lot and product type and final release assay testing. This product is received as preformulated bulk, and is manufactured, labeled, and packaged by Pfizer. The final scope was determined to be lot 30155BA. No quality issues were identified during the investigation. There is no impact on product quality. An NTM was not issued for the complaint. No regulatory notification or SQRTs/AQRTs were held because of this complaint. The complaint condition of lack of effect was not confirmed, therefore the root cause cannot be attributed to the manufacture or vendor processes as incoming quality component testing and all analytical tests performed at the time of lot release confirmed that the batch met potency specifications.  No corrective or preventative actions are required as the complaint condition was not determined to be manufacture or vendor related and there are quality systems in place to detect defects prior to any lot being released to the market.  No follow-up attempts are possible. No further information is expected.