By Melissa Badamo - Last Updated: April 4, 2024
Consolidative hematopoietic stem cell transplantation (HSCT) after blast reduction therapy improved long-term survival benefit in patients with accelerated and blast phase myeloproliferative neoplasms (MPN), according to a study published in Blood Advances.
Marta Davidson, MD, of the Princess Margaret Cancer Centre, and colleagues performed a retrospective analysis of patients with accelerated and blast phase MPN (n=138) treated with acute myeloid leukemia–type intensive (n=81) and nonintensive (n=57) blast-reduction strategies.
Intensive blast-reduction therapy included daunorubicin plus cytarabine arabinoside and FLAG-IDA or mitoxantrone, etoposide, and high-dose cytarabine (NOVE-HiDAC). Nonintensive blast reduction therapy included hypomethylating agents (HMA) with either azacitidine, decitabine, or azacitidine plus venetoclax.
The researchers evaluated and compared responses to blast reduction using both criteria developed at Princess Margaret Cancer Centre and the European LeukemiaNet (ELN) 2022 AML response criteria.
The primary endpoint was overall best response after blast-reduction therapy. Overall best response comprised of complete response (CR), complete remission with incomplete hematologic recovery (CRi), and reversion to chronic phase MPN (cMPN). Other endpoints included overall survival (OS) and the proportion of patients undergoing HSCT.
The overall best response was 77% in the intensive groups, and 39% in the nonintensive groups.
In the intensive therapy groups, similar overall best response rates were observed in patients receiving induction with daunorubicin plus cytarabine arabinoside compared with FLAG-IDA or NOVE-HiDAC (74% vs 78%, respectively; P=0.78). However, patients receiving daunorubicin plus cytarabine required second inductions more often (29% vs 4%, respectively; P=0.002).
In the nonintensive therapy groups, responses were observed in 33% of patients treated with HMA alone, with 92% of those responses resulting in reversion to cMPN. Half (50%) of patients treated with azacitidine plus venetoclax responded to treatment.
TP53 and RAS pathway mutations were associated with inferior treatment response in the intensive therapy groups, while poorer Eastern Cooperative Oncology Group (ECOG) performance status was associated with inferior treatment response in both intensive and nonintensive therapy groups.
Using the PM criteria, improved OS was observed in patients achieving cMPN. However, no difference in survival was observed by the ELN 2022 response criteria.
The researchers also compared the proportion of patients undergoing HSCT after first-line intensive or nonintensive blast reduction treatment and found no survival differences between the two blast reduction strategies.
“[Accelerated and blast phase MPN] represents an ongoing area of unmet need for the development of effective disease-modifying therapies,” Dr. Davidson and colleagues wrote. “The current study confirms our previous findings that consolidation with [HSCT] after blast reduction is required to achieve long-term survival benefit…moreover, we show that both intensive and nonintensive blast-reduction strategies can be used as a bridge to [HSCT] in carefully selected patients.”
Reference
Davidson MB, Kennedy JA, Capo-Chichi JM, et al. Outcomes of intensive and nonintensive blast-reduction strategies in accelerated and blast-phase MPN. Blood Adv. 2024. doi:10.1182/bloodadvances.2023011735
Original Source: Study Compares Blast Reduction Strategies in Accelerated, Blast Phase MPN | Blood Cancers Today