Risk of hepatitis B and tuberculosis reactivation in patients with neuromyelitis optica spectrum disorder undergoing B cell depletion therapy

Introduction B cell-depleting agents are highly effective in preventing relapses in neuromyelitis optica spectrum disorder (NMOSD). Currently, no standardized guidelines exist for preventing hepatitis B reactivation (HBVr) or tuberculosis reactivation (TBr) during the use of B cell-depleting agents in patients with NMOSD who are at risk of HBVr or TBr. Furthermore, data on HBVr and TBr in such patients remain limited. Objective This study aimed to evaluate the risk of HBVr and TBr in patients with NMOSD undergoing B cell depletion therapy and to explore the corresponding prophylactic strategy against HBVr and TBr. Methods Patients with NMOSD treated with inebilizumab or rituximab at the Third Affiliated Hospital of Sun Yat-sen University between January 1, 2016, and August 31, 2024, were screened for potential risks of HBVr and TBr. The incidence of HBVr and TBr during treatment with B cell-depleting agents was analyzed. Results Among 102 patients with NMOSD receiving B cell-depleting agents (36 patients treated with inebilizumab and 66 with rituximab), 42 were at risk of HBVr (2 HBsAg-positive and 40 HBsAg-negative and anti-HBc-positive), and 11 were at risk of TBr (2 prior TB infection and 9 latent tuberculosis infection [LTBI]). For the HBVr-risk cohort, the median follow-up duration was 11.5 months (6-21 months). Both of these two patients with HBsAg-positive received prophylactic anti-HBV treatment. One of these two patients experienced HBVr, and responsed well to continuing anti-HBV medications and polyene phosphatidylcholine capsules. Among the 40 HBsAg-negative and anti-HBc-positive patients, 11 received prophylactic anti-HBV treatment, and none of these 40 patients experienced HBVr. For the TBr-risk cohort, the median follow-up duration was 11 months (7-17 months). Two patients with prior cured TB infections did not receive prophylactic anti-TB treatment, and no TBr was observed. Similarly, nine patients with LTBI did not receive prophylactic anti-TB treatment, and no active TB was identified during follow-up. Conclusion Patients with NMOSD who were HBsAg-negative and anti-HBc-positive or had LTBI had no observed instances of HBVr/TBr while receiving B cell depletion therapy during the follow-up period, with or without prophylactic anti-HBV or anti-TB treatment.