Stevens-Johnson syndrome; This literature-non-study case was reported in a literature article and describes the occurrence of STEVENS-JOHNSON SYNDROME (Stevens-Johnson syndrome) in a 46-year-old patient of an unknown gender who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.       No Medical History information was reported.    On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced STEVENS-JOHNSON SYNDROME (Stevens-Johnson syndrome) (seriousness criterion medically significant). At the time of the report, STEVENS-JOHNSON SYNDROME (Stevens-Johnson syndrome) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Histology: showed full-thickness epidermal necrosis.     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Concomitant and treatment medications were not reported.  This study was conducted from December 24, 2020 to May 19, 2021 and 803 cases were reported. 78 providers indicated that a skin biopsy was performed. Records listed as pending (n = 15) or incomplete (n = 5) were not included, leaving 58 complete biopsy reports for review.  8 patients biopsied after the first dose were not planning to receive the second dose, given the severity of the cutaneous reaction. These included 2 cases of leukocytoclastic vasculitis, 2 cases of papulosquamous eruptions, 1 case of urticaria, 1 case of dermal hypersensitivity reaction, 1 case of bullous pemphigoid, and 1 case of Stevens-Johnson syndrome.  Patient experienced Stevens-Johnson syndrome which distributed on all skin surfaces, oral and genital mucosa. Morphology was reported as atypical targetoid papules with duskiness, bullae and epidermal necrosis in the center. Hemorrhagic crusting on the vermillion lips, lesions involved palms and soles.  The mechanism of V-REPP after COVID-19 vaccination is unknown, but the delayed occurrence of these reactions suggests 2 potential mechanisms: (1) delayed hypersensitivity response to vaccination (2) T-cell-mediated skin reaction due to molecular mimicry with a viral epitope.  Author stated immune-mediated dermatologic disorders, such as bullous pemphigoid and leukocytoclastic vasculitis potentially driven by off-target immune activation following COVID-19 vaccination. These shifts in the immune response after vaccination may also be associated with reactivation of other viruses.  This case referred to the patient who experienced Stevens-Johnson syndrome after moderna vaccination.  Company comment: This literature non-study case concerns a 46 year old patient of unknown gender, with no reported medical history, who experienced the unexpected serious (medically significant) AESI of Stevens-Johnson syndrome, unknown days after receiving the first dose of mRNA-1273 vaccine. Patient experienced Stevens-Johnson syndrome on all skin surfaces, oral and genital mucosa. Morphology was reported as atypical targetoid papules with duskiness, bullae and epidermal necrosis in the center. Hemorrhagic crusting on the vermillion lips, lesions involved palms and soles. Histopathology showed full-thickness epidermal necrosis. Authors stated that the mechanism of V-REPP (vaccine-related eruption of papules and plaques) after COVID-19 vaccination was unknown, but the delayed occurrence of these reactions suggests 2 potential mechanisms: (1) delayed hypersensitivity response to vaccination (2) T-cell-mediated skin reaction due to molecular mimicry with a viral epitope. No information on treatment of the event and outcome was available in the report. The benefit-risk relationship of mRNA-1273 is not affected by this report.   This case was linked to US-MODERNATX, INC.-MOD-2022-691096, US-MODERNATX, INC.-MOD-2022-691095, US-MODERNATX, INC.-MOD-2022-691094, US-MODERNATX, INC.-MOD-2022-691091, US-MODERNATX, INC.-MOD-2022-691090, US-MODERNATX, INC.-MOD-2022-691089, US-MODERNATX, INC.-MOD-2022-691088, US-MODERNATX, INC.-MOD-2022-691086, US-MODERNATX, INC.-MOD-2022-691085 (E2B Linked Report).   Most recent FOLLOW-UP information incorporated above includes: On 23-Dec-2022: Live follow up received by safety on 23-Dec-2022 has email received and contains significant information: Reporter information, literature information, laboratory tests, product details, event information and narrative were updated.; Reporter's Comments: This literature non-study case concerns a 46 year old patient of unknown gender, with no reported medical history, who experienced the unexpected serious (medically significant) AESI of Stevens-Johnson syndrome, unknown days after receiving the first dose of mRNA-1273 vaccine. Patient experienced Stevens-Johnson syndrome on all skin surfaces, oral and genital mucosa. Morphology was reported as atypical targetoid papules with duskiness, bullae and epidermal necrosis in the center. Hemorrhagic crusting on the vermillion lips, lesions involved palms and soles. Histopathology showed full-thickness epidermal necrosis. Authors stated that the mechanism of V-REPP (vaccine-related eruption of papules and plaques) after COVID-19 vaccination was unknown, but the delayed occurrence of these reactions suggests 2 potential mechanisms: (1) delayed hypersensitivity response to vaccination (2) T-cell-mediated skin reaction due to molecular mimicry with a viral epitope. No information on treatment of the event and outcome was available in the report. The benefit-risk relationship of mRNA-1273 is not affected by this report.; Sender's Comments:  US-MODERNATX, INC.-MOD-2022-691094:1 Adult Patient US-MODERNATX, INC.-MOD-2022-691091:1 Adult Patient US-MODERNATX, INC.-MOD-2022-691085:42-years-old US-MODERNATX, INC.-MOD-2022-691089:27-years-old US-MODERNATX, INC.-MOD-2022-691088:67-years-old US-MODERNATX, INC.-MOD-2022-691095:1 Elderly Patient US-MODERNATX, INC.-MOD-2022-691086:38-years-old US-MODERNATX, INC.-MOD-2022-691096:Cluster case US-MODERNATX, INC.-MOD-2022-691090:1 Adult Patient