fulminant liver failure/acute lever failure; Hepatomegaly; received three 20-mcg doses of Engerix-B® at zero, eight, and eleven months; HBsAg and HBcAb newly reactive; This serious case was reported in a literature article and described the occurrence of hepatitis b in a 33-year-old male patient who received HBV (Engerix B adult) for prophylaxis.  Co-suspect products included HBV (Engerix B adult) for prophylaxis, dolutegravir for hiv infection and darunavir + ritonavir for hiv infection.   Concurrent medical conditions included virologic failure (on TAF-FTC-RPV), viral hepatitis c, viral mutation identified (M184V, K65R, K103N, and E138Q mutations) and viral resistance. Concomitant products included tenofovir alafenamide fumarate, emtricitabine, rilpivirine and HEPATITIS B VACCINE (ENGERIX B ADULT).   On an unknown date, the patient received the 3rd dose of Engerix B adult 20 ug, the 2nd dose of Engerix B adult 20 ug, dolutegravir and darunavir + ritonavir. On an unknown date, an unknown time after receiving Engerix B adult, not applicable after receiving Engerix B adult and an unknown time after starting dolutegravir, the patient experienced hepatitis b (Verbatim: HBsAg and HBcAb newly reactive) (serious criteria GSK medically significant), fulminant hepatic failure (Verbatim: fulminant liver failure/acute lever failure) (serious criteria hospitalization, GSK medically significant and clinically significant/intervention required), hepatomegaly (Verbatim: Hepatomegaly) and drug dose administration interval too long (Verbatim: received three 20-mcg doses of Engerix-B® at zero, eight, and eleven months). Dolutegravir was discontinued (Dechallenge was positive). The action taken with darunavir + ritonavir was unknown. The outcome of the hepatitis b, fulminant hepatic failure and hepatomegaly were resolved and the outcome of the drug dose administration interval too long was unknown.   It was unknown if the reporter considered the hepatitis b, fulminant hepatic failure and hepatomegaly to be related to Engerix B adult and Engerix B Pre-Filled Syringe Device. The reporter considered the hepatitis b, fulminant hepatic failure and hepatomegaly to be related to dolutegravir.     It was unknown if the company considered the hepatitis b, fulminant hepatic failure and hepatomegaly to be related to Engerix B adult and Engerix B Pre-Filled Syringe Device. The company considered the hepatitis b, fulminant hepatic failure and hepatomegaly to be related to dolutegravir.   This report is made by GSK without prejudice and does not imply any admission or liability for the incident or its consequences.   Additional Information: GSK Receipt Date: 29-Jun-2023 This case corresponds to case-2 reported in this literature article.  The patient presented with Human immunodeficiency virus (HIV), initially suppressed on tenofovir alafenamide (TAF)- EMTRICITABIN (FTC)- RILPIVIRINE (RPV) but subsequently with virologic failure. CD4 was 300 cells/mL and HIV viral load (VL) was 30,000 copies/mL despite treatment adherence. Hepatitis B surface antigen (HBsAg), Hepatitis B core antibody (HBcAb), and Hepatitis B surface antibody (HBsAb) were nonreactive. The patient received three 20-mcg doses of Engerix-B at zero, eight, and eleven months. HBsAb three months later was 41 mIU/mL. Hepatitis C virus (HCV) infection was diagnosed with Hepatitis C virus (HCV) viral load (VL) of 386,000 IU/mL. HIV genotype revealed M184V, K65R, K103N, and E138Q mutations, prompting switch to Dolutegravir (DTG) and ritonavir-boosted darunavir (DRV/r). The patient presented four months later in acute liver failure (alanine transaminase (ALT) 2,640 U/L, bilirubin 17 mg/dL, international normalized ratio (INR) 3.1, from normal baselines). HBsAg and HBcAb immunoglobulin M (IgM) were newly reactive; Hepatitis B virus (HBV) DNA was 380 million IU/mL. HIV and HCV VL were undetectable. The patient reported multiple potential HBV exposures. The patient was treated with TAF and evaluated for transplant given fulminant liver failure but recovered and was discharged two weeks later. On six-month follow-up, HBV DNA was suppressed, and anti-retroviral therapy (ART) was simplified to TAF-FTC-bictegravir (BIC) and doravirine (DOR) with continued follow-up. This case highlighted the importance of post vaccine surveillance in persons with low antibody titers, which might not be sustained or sufficient to prevent infection, and consideration of maintaining HBV-active ART in those at risk of infection.; Sender's Comments:  US-GSK-US2023GSK091095:Same article