RecruitingPhase 3Drug trialThe Efficacy and Safety of Pola-ZR2 Versus ZR2 in the Treatment of Old Patients With de Novo Diffuse Large B-cell LymphomaA multicenter, prospective, randomized, open-label, controlled trial to evaluate the efficacy and safety of Pola-ZR2 (polatuzumab vedotin, zanubrutinib, rituximab and lenalidomide) versus ZR2 (zanubrutinib, rituximab and lenalidomide) in the treatment of old patients with de novo diffuse large B-cell lymphoma