kidney transplant recipients who developed COVID-19 more than 14 days after receipt of 2 doses of SARSCoV- 2 mRNA vaccine, administered at the recommended dosing interval; kidney transplant recipients who developed COVID-19 more than 14 days after receipt of 2 doses of SARSCoV- 2 mRNA vaccine, administered at the recommended dosing interval; This author reported similar events in four patients. This is second of four reports.  A 71-year-old male subject received two doses of bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE) dose 1 and dose 2 via an unspecified route of administration on an unspecified date (Batch/Lot number was not reported) as single dose for COVID-19 immunization. Medical history included renal transplant and calcineurin inhibitor-based immunosuppression. Time from transplant to 1st vaccine was 248 months. Thymoglobulin was not received 6 months prior to 1st vaccine dose. The subject's concomitant medications included prednisone and tacrolimus for maintenance immunosuppression. No MMF/ Aza was stopped or reduced. The subject developed COVID-19 more than 14 days after receipt of 2 doses of vaccine, administered at the recommended dosing interval. Symptoms started after 58 days from 2nd dose, including weakness, cough. SARSCOV-2 test was performed after 62 days from 2nd dose and was positive. Casirivimab and imdevimab were not given. The subject was hospitalized for 4 days, was not admitted to ICU, not requiring mechanical ventilation, no O2 supplement on discharge. Disposition was at home. Duration of follow-up was 79 days. The subject was still alive at time of last follow-up. The outcome of events was unknown.  Recently, a study showed that only 54% of organ transplant recipients developed a positive antibody response after 2 doses of SARS-CoV-2 mRNA vaccine and, among kidney transplant recipients, only 48% had an antibody response 4. At our center the seropositivity rate in organ transplant recipients was 37.2% 5.This suggests that a significant proportion of transplant recipients remain at risk for COVID-19 despite completing the vaccination series. Our center encourages COVID-19 vaccination for all transplant recipients. We estimate an active follow-up of approximately 1,680 fully vaccinated kidney transplant recipients. We had 8 kidney transplant recipients who developed COVID-19 more than 14 days after receipt of 2 doses of SARSCoV- 2 mRNA vaccine, administered at the recommended dosing interval (table). All patients were symptomatic, most commonly with fatigue and cough. The median age was 65 years old (range 36-73), 50% had received a previous transplant, the median time from the most recent transplant to the first dose of mRNA vaccine was 31 months (range 3 - 248), and 3 out of 8 patients had received thymoglobulin for induction in the 6 months preceding vaccination. All patients were on calcineurin inhibitor (CNI)-based immunosuppression and 7 of the 8 were on mycophenolate mofetil. CNI level goals were not changed during illness, anti-metabolite doses were reduced or held based on symptoms and severity, at the discretion of the nephrologist. Symptom onset and SARS-CoV-2 testing occurred at a median of 56 days (range 18-77) and 59 days (range 20-77) after the second dose of the vaccine, respectively. Three patients received casirivimab/imdevimab as outpatient and did not require hospital admission. Three patients were hospitalized and had a length of stay of 3 to 5 days, without requiring ICU admission or mechanical ventilation. All were discharged to home without oxygen. None of the patients had anti-SARS-CoV-2 spike protein antibody checked after vaccination or disease and viruses were not sequenced. Data on the COVID-19 vaccine effectiveness is emerging, however, vaccine effectiveness in the immunocompromised population is lacking. It is encouraging that our breakthrough cases of COVID-19 after vaccination were mild and associated with good outcomes. However, we should continue to encourage our patients to be vaccinated and also encourage vaccination of household members and close contacts. Recent guidance allowing fully vaccinated individuals to resume prepandemic activities probably should not apply to transplant recipients.  No follow-up attempts are possible, information about batch number cannot be obtained.; Sender's Comments: Based on the information currently available, a lack of efficacy with bnt162b2 towards the breakthrough COVID-19 infection following vaccination in this patient cannot be completely excluded.,Linked Report(s) :PFIZER INC-202101115297 Same article/ drug/event and different patient: