received a 3 series unknown Hep B vaccination in 1996 / not converting / titer testing: 20-NOV-2019; Drug dose administration interval too short/1st 29Jul2020,2nd 26Aug2020, and 3rd 23Dec2020.; received a 3 series unknown Hep B vaccination in 1996 / not converting / titer testing: 20-NOV-2019; received a 3 series unknown Hep B vaccination in 1996 / not converting / titer testing: 20-NOV-2019; This case was reported by a nurse via call center representative and described the occurrence of therapy non-responder in a 24-year-old female patient who received HBV (Engerix B) (batch number L5C49, expiry date 17th May 2022) for prophylaxis.   Co-suspect products included hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, HBV (Engerix B) (batch number L5C49, expiry date 17th May 2022) for prophylaxis, hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, HBV (Engerix B) (batch number H2T35, expiry date 29th May 2022) for prophylaxis, hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, HBV (Engerix B) (batch number H2T35, expiry date 29th May 2022) for prophylaxis, hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, HBV (Engerix B) for prophylaxis, hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, HBV (Engerix B) for prophylaxis, hepatitis B vaccine pre-filled syringe device (Engerix B Pre-Filled Syringe Device) injection syringe for prophylaxis, Hepatitis B vaccine for prophylaxis, Hepatitis B vaccine for prophylaxis and Hepatitis B vaccine for prophylaxis.   On 23rd December 2020, the patient received the 3rd dose of Engerix B and Engerix B Pre-Filled Syringe Device. On 26th August 2020, the patient received the 2nd dose of Engerix B and Engerix B Pre-Filled Syringe Device. On 29th July 2020, the patient received the 1st dose of Engerix B and Engerix B Pre-Filled Syringe Device. On 26th May 2020, the patient received the 3rd dose of Engerix B and Engerix B Pre-Filled Syringe Device. In December 2019, the patient received the 2nd dose of Engerix B and Engerix B Pre-Filled Syringe Device. In November 2019, the patient received the 1st dose of Engerix B and Engerix B Pre-Filled Syringe Device. On an unknown date, the patient received the 1st dose of Hepatitis B vaccine, the 2nd dose of Hepatitis B vaccine and the 3rd dose of Hepatitis B vaccine. On 20th November 2019, not applicable after receiving Engerix B, Engerix B Pre-Filled Syringe Device, Engerix B, Engerix B Pre-Filled Syringe Device, Engerix B, Engerix B Pre-Filled Syringe Device, Engerix B, Engerix B Pre-Filled Syringe Device, Engerix B, Engerix B Pre-Filled Syringe Device, Engerix B and Engerix B Pre-Filled Syringe Device and more than 2 years after receiving Hepatitis B vaccine, Hepatitis B vaccine and Hepatitis B vaccine, the patient experienced therapy non-responder. On 20th July 2020, the patient experienced therapy non-responder. In December 2020, the patient experienced drug dose administration interval too short. On 26th February 2021, the patient experienced therapy non-responder. On an unknown date, the outcome of the therapy non-responder, therapy non-responder, therapy non-responder and drug dose administration interval too short were unknown.   This report is made by GSK without prejudice and does not imply any admission or liability for the incident or its consequences.  Additional details were reported as follows: The age at vaccination was not reported but could be less than 1 year for Hep B vaccination. In 1996, the patient received a 3 series unknown Hep B vaccination. On 20th November 2019, the titer was tested, and the patient was found to be not converting. Since the patient was not converting, she then received 3 doses of Engerix B.  On 20th July 2020, the titer was again tested, and the patient was found to be not seroconverting. The patient then received 2 doses of Engerix B and last dose earlier then recommended scheduled, which led to shortening of vaccination schedule. On 26th February 2021, the titer was again tested, and the patient was found to be not seroconverting. The reporter consented to follow-up.