A Systematic Review of the Clinical Efficacy of Treatments in Relapsed or Refractory Diffuse Large B Cell Lymphoma

Introduction Novel treatment options are needed to improve outcomes in transplant-ineligible relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). This systematic literature review evaluated clinical evidence on treatments for patients with R/R DLBCL ineligible for, or relapsed following, stem cell transplantation. Methods We assessed the feasibility of conducting an indirect treatment comparison (ITC) or network meta-analysis (NMA) to evaluate the relative efficacy and safety of polatuzumab vedotin in combination with bendamustine + rituximab versus other relevant treatments. Results Thirty-seven studies were identified, of which 20 were eligible [seven randomized, controlled trials (RCTs); 13 observational/single-arm trials]. Due to a lack of RCTs, an ITC/NMA summary of the relative efficacy and safety of the treatment options was not possible. Only two of the seven RCTs had positive outcomes. Conclusions These findings highlight the paucity of published RCTs to establish the comparative efficacy of treatments for transplant-ineligible R/R DLBCL and lack of standard of care in this setting.