Acute kidney injury(AKI) secondary to tacrolimus; interchange of vaccine product; Home COVID-19 Virus test was positive; This spontaneous case was reported by a pharmacist and describes the occurrence of ACUTE KIDNEY INJURY (Acute kidney injury(AKI) secondary to tacrolimus) in a male patient of an unknown age who received mRNA-1273 (Moderna COVID-19 Vaccine) for Prophylactic vaccination. The occurrence of additional non-serious events is detailed below.    Co-suspect product included non-company product TACROLIMUS for an unknown indication.    The patient's past medical history included Kidney transplant on 02-Sep-2020. Previously administered products included for Immunisation: JANSSEN COVID-19 VACCINE (Dose no-1 and Route of Administration and lot no- unknow) on 10-Mar-2021. Past adverse reactions to the above products included No adverse event with JANSSEN COVID-19 VACCINE. Concurrent medical conditions included Gout, Hyperlipidemia and Hypertension. Concomitant products included CARVEDILOL, ALLOPURINOL, COLECALCIFEROL, FENOFIBRATE, FISH OIL, MYCOPHENOLATE MOFETIL, ACETAMINOPHEN, PREDNISONE, SEMAGLUTIDE, SIMVASTATIN from an unknown date to 17-May-2022 and TAMSULOSIN HYDROCHLORIDE (TAMULOSIN) from an unknown date to 17-May-2022 for an unknown indication.   On 28-Oct-2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 18-Mar-2022, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient started TACROLIMUS (Oral) at an unspecified dose. On 17-May-2022, the patient experienced SARS-COV-2 TEST POSITIVE (Home COVID-19 Virus test was positive). On 21-May-2022, the patient experienced ACUTE KIDNEY INJURY (Acute kidney injury(AKI) secondary to tacrolimus) (seriousness criteria hospitalization and medically significant). On an unknown date, the patient experienced INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine product). The patient was hospitalized from 21-May-2022 to 23-May-2022 due to ACUTE KIDNEY INJURY. The patient was treated with NIRMATRELVIR, RITONAVIR (PAXLOVID) from 17-May-2022 to 21-May-2022 for COVID-19 treatment, at a dose of UNK, bid and PHENYTOIN on 21-May-2022 for Acute kidney injury, at a dose of 300 milligram, 2 doses. In May 2022, SARS-COV-2 TEST POSITIVE (Home COVID-19 Virus test was positive) had resolved. At the time of the report, ACUTE KIDNEY INJURY (Acute kidney injury(AKI) secondary to tacrolimus) and INTERCHANGE OF VACCINE PRODUCTS (interchange of vaccine product) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 10-May-2022, Blood creatinine (1.5-1.8): 2.25 (High) 2.25 g/dl. On 17-May-2022, SARS-CoV-2 test: positive (Positive) Positive. On 21-May-2022, Blood creatinine (1.5-1.8): 2.59 (High) 2.59 g/dl. On 21-May-2022, Blood test: 75.6 (High) Tacrolimus level in blood- 75.6 ng/ml. On 23-May-2022, Blood creatinine (1.5-1.8): 2.48 (High) 2.48 g/dl.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Concomitant medication included multivitamins. On 10 May 2022, patient went to emergency room as he experienced nausea and weakness. Tacrolimus level was not drawn and was instructed to hold when discharged from ER. Suspected clinical vaccination failure was also attributable to dose 1 (Janssen) as reported. During ER visit, interaction with Paxlovid and tacrolimus was identified. On 21 May 2022, he was treated with fluids. On 23 May 2022, patient was told to hold on tacrolimus, simvastatin and tamsulosin.The causality as per reporter Janssen was provided as possible.  Company Comment: This is a spontaneous case concerning a unspecified old male with past medical history of renal transplant on (02-Sep-2020), Concurrent medical conditions included Gout, and Hypertension, who experienced the unexpected serious (hospitalization, medically significant) event of acute kidney injury, which occurred 3 days after third dose of mRNA-1273 vaccine. The patient previously received a different Covid-19 vaccine COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (Janseen) (interchange of vaccine products) 1 year prior to  mRNA-1273 It is reported that patient felt nausea and weak, serum creatinine was 2.25g/dl, Tacrolimus level was not drawn, patient got discharged with instruct to hold Tacrolimus. After 7 days home covid virus test is positive. Patient prescribed with Paxlovid twice a day for 5 days from 17- may-2022 to 21-may-2022. In emergency room interaction between paxlovid and Tacrolimus is identified, patient advised to hold simavastin and Tacrolimus. Tacrolimus level 75.6ng/ml, creatinine 2.59 g/dl, patient got admitted for acute kidney injury secondary to Tacrolimus toxicity patient started on iv fluids, phenytoin 300 mg 2 doses was given, patient was hospitalized for 2 days and got discharged with serum creatinine of 2.48, patient advised to hold Tacrolimus, simvastatin, tamsulosin. Concomitant medication Paxlovid, Tacrolimus is confounding for the event acute kidney injury, past medical history of renal transplant on (02-Sep-2020) and Concurrent medical conditions included Gout, and Hypertension is confounding for the event. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a spontaneous case concerning a unspecified old male with past medical history of renal transplant on (02-Sep-2020), Concurrent medical conditions included Gout, and Hypertension, who experienced the unexpected serious (hospitalization, medically significant) event of acute kidney injury, which occurred 3 days after third dose of mRNA-1273 vaccine. The patient previously received a different Covid-19 vaccine COVID-19 VACCINE NRVV AD26 (JNJ 78436735) (Janseen) (interchange of vaccine products) 1 year prior to  mRNA-1273 It is reported that patient felt nausea and weak, serum creatinine was 2.25g/dl, Tacrolimus level was not drawn, patient got discharged with instruct to hold Tacrolimus. After 7 days home covid virus test is positive. Patient prescribed with Paxlovid twice a day for 5 days from 17- may-2022 to 21-may-2022. In emergency room interaction between paxlovid and Tacrolimus is identified, patient advised to hold simavastin and Tacrolimus. Tacrolimus level 75.6ng/ml, creatinine 2.59 g/dl, patient got admitted for acute kidney injury secondary to Tacrolimus toxicity patient started on iv fluids, phenytoin 300 mg 2 doses was given, patient was hospitalized for 2 days and got discharged with serum creatinine of 2.48, patient advised to hold Tacrolimus, simvastatin, tamsulosin. Concomitant medication Paxlovid, Tacrolimus is confounding for the event acute kidney injury, past medical history of renal transplant on (02-Sep-2020) and Concurrent medical conditions included Gout, and Hypertension is confounding for the event. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.