Homoharringtonine, BCL-2 Inhibitor, Rituximab, and Prednisone in Relapsed/Refractory Diffuse Large B-Cell Lymphoma

Summary

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma in China and worldwide. Although standard immunochemotherapy with Rituximab, Cyclophosphamide, Doxorubicin Hydrochloride, Vincristine (Oncovin), and Prednisone (R-CHOP) achieves durable remissions in many patients, approximately 30-40% experience relapse or refractory disease with poor outcomes. Novel strategies are needed for patients who are not candidates for transplantation or who relapse after multiple lines of therapy. Homoharringtonine (HHT) is a natural cephalotaxine alkaloid extracted from Cephalotaxus species, clinically approved in China for acute and chronic myeloid leukemias. It inhibits ribosomal protein synthesis, modulates oncogenic and epigenetic signaling pathways, and induces apoptosis through mitochondrial and stress-activated pathways. Importantly, HHT downregulates the anti-apoptotic protein Myeloid Cell Leukemia 1 (MCL-1), a critical resistance factor to B-cell lymphoma 2 (BCL-2) inhibitors. This provides a strong mechanistic rationale for combining HHT with a BCL-2 inhibitor, together with rituximab and prednisone, in relapsed/refractory DLBCL. This prospective, multicenter, single-arm, Phase Ib/II study will evaluate the safety, tolerability, and efficacy of HHT, a BCL-2 inhibitor, rituximab, and prednisone in adult patients with relapsed/refractory DLBCL. Phase Ib will enroll 15-22 patients to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), and the recommended phase II dose (RP2D) of HHT. Phase II will enroll 40 patients treated at RP2D to evaluate the overall response rate (ORR) after 3 and 6 cycles per Lugano 2014 criteria. Secondary endpoints include complete remission (CR), partial remission (PR), progression-free survival (PFS), and overall survival (OS). Exploratory analyses will incorporate molecular biomarkers such as genomic profiling, circulating tumor DNA (ctDNA), and spatial transcriptomics.

Timeline

Start

2025-09-08

Primary completion

2027-08-01

Completion

2028-08-01

Drugs

Indications