The Evolving Therapeutic Landscape of Richter Transformation

Richter transformation (RT), the progression of chronic lymphocytic leukemia (CLL) to aggressive lymphomas, poses a significant therapeutic challenge with historically poor outcomes. Chemoimmunotherapy (CIT) regimens have demonstrated limited efficacy with short durations of response. This review aims to evaluate the evolving treatment landscape for RT, with a focus on recent advances in targeted therapies, immunotherapies, and cellular therapies that are redefining the current and future standards of care.

The treatment paradigm for RT is rapidly shifting away from cytotoxic chemotherapy. The combination of the B-cell lymphoma 2 inhibitor venetoclax with CIT has emerged as a new first-line benchmark with promising response rates and overall survival. Covalent Bruton tyrosine kinase (BTK) inhibitors had modest activity as monotherapy but showed improved responses when given with an immune checkpoint inhibitor. Pirtobrutinib has demonstrated responses even in heavily pretreated patients. Furthermore, advancement in immunotherapy has expanded treatment options for this patient population with bispecific T-cell engagers achieving high response rates and chimeric antigen receptor T-cell therapy providing deep, durable responses and favorable median overall survival in the relapsed/refractory (R/R) setting. The therapeutic landscape for RT has broadened with the introduction of targeted agents and immunotherapy. Venetoclax-based regimens represent a new standard for chemotherapy-eligible patients, allowing for a more effective bridge to potentially curative consolidation with transplantation. For R/R disease, novel BTK inhibitors, bispecific antibodies, and cellular therapies are demonstrating substantial efficacy. Ongoing trials investigating combinations of these agents are poised to further transform RT management.