Comparison of efficacy of hepatitis B vaccination during induction versus maintenance phase of chemotherapy in acute lymphoblastic leukemia: A nonrandomized clinical trial

Background: Acute lymphoblastic leukemia (ALL) patients are susceptible to hepatitis B infection due to profound immunosuppression and repeated transfusions. However, the comparative effectiveness of hepatitis B vaccination in different phases of chemotherapy has not been studied. Aim: In this comparative interventional study (CTRI/2017/08/009402), vaccination in the induction phase (IP) was compared to that in the maintenance phase (MP). Materials and Methods: The participating ALL patients in both groups (29 per group) were vaccinated with double the dose of hepatitis B vaccine at 0, 1, and 2 months. The proportion of patients with seroprotective anti-hepatitis B surface titers (>10 IU/ml) was compared between the two groups after each dose. Results: The seroprotection rates between both the phases were similar following the first (relative risk [RR] = 4, confidence interval [CI]: 0.47–33.65) and third (RR = 1.4, CI: 0.73-2.84) doses of vaccination, whereas following the second dose of vaccination, the seroprotection rate in IP was significantly higher than that of MP (RR = 1.9, CI: 1.07–3.35). Conclusion: This study concluded that a 0, 1, and 2 schedule of hepatitis B vaccination has similar efficacy in both the IP and the MP of chemotherapy in ALL patients. As the IP has a higher trend of seroprotection rates compared to MP, vaccination in IP followed by revaccination postchemotherapy may be preferred in countries with a high prevalence of hepatitis B infection.