Zuberitamab for EBV Infection Post-Allo-HSCT

EBV DNAemia is defined as the presence of EBV-DNA load in peripheral blood exceeding the normal threshold, serving as a key diagnostic indicator for EBV-associated post-transplant lymphoproliferative disorder (EBV-PTLD). According to the European Conference on Infections in Leukemia (ECIL-6) guidelines, regular monitoring of peripheral blood EBV-DNA levels via quantitative real-time PCR (qPCR) is recommended starting from the first month after allogeneic hematopoietic stem cell transplantation (allo-HSCT), with a weekly frequency sustained for at least 4 months post-transplant. For HSCT patients who develop EBV DNAemia, preemptive therapy should be initiated promptly. EBV-PTLD is a serious complication that may progress rapidly; if not diagnosed and treated in a timely manner, mortality rates can reach 60-80%. Current guidelines recommend CD20 monoclonal antibody (rituximab) as the first-line preemptive treatment. The response rate to rituximab is approximately 84%. The typical regimen consists of 375 mg/m² per dose, administered weekly, with 1-4 doses generally sufficient to achieve treatment goals. However, a subset of patients exhibits poor response to first-line therapy and requires second-line interventions, such as EBV-specific cytotoxic T lymphocytes (EBV-CTLs), donor lymphocyte infusion, or combination chemotherapy.

Zuberitamab is a novel anti-CD20 monoclonal antibody and the first Class 1 innovative biologics targeting CD20 developed in China. Preclinical studies have demonstrated that zuberitamab exhibits stronger antibody-dependent cellular cytotoxicity (ADCC) activity compared to rituximab. In a pivotal Phase III registrational clinical study, zuberitamab combined with CHOP (Hi-CHOP) was evaluated head-to-head against R-CHOP in patients with diffuse large B-cell lymphoma (DLBCL). The results showed an improvement in the complete response (CR) rate by more than 8% (85.7% vs. 77.3%, P = 0.038). These findings indicate that zuberitamab holds significant advantages over rituximab in terms of both biological activity and clinical efficacy. Based on this evidence, we have initiated a Phase II clinical trial to evaluate the efficacy and safety of zuberitamab as first-line preemptive therapy for EBV infection. This is a prospective Phase II clinical trial enrolling patients with EBV infection following transplantation. Zuberitamab will be administered as first-line preemptive therapy.