New agents in MPN

Srdan Verstovsek, Moshe Talpaz, Martha Wadleigh, Jeanne Palmer, et al.

A RANDOMIZED, DOUBLE BLIND PHASE 2 STUDY OF 3 DIFFERENT DOSES OF PRM-151 IN PATIENTS WITH MYELOFIBROSIS WHO WERE PREVIOUSLY TREATED WITH OR INELIGIBLE FOR RUXOLITINIB

Conclusion: The study enrolled a large proportion of MF pts with advanced disease (Int-2 or high risk, BMF grade 3, anemic/transfusion dependent, and PLT <50 x 109/L). Decrease in BMF and collagen grade were observed across all dose levels. Increases in Hgb and PLT count or reduction in transfusion requirements were also reported across all dose levels. Improvements in MPN-SAF TSS and spleen volume were observed in a proportion of pts.  PRM-151 treatment for up to 9 cycles was well tolerated. These data warrant confirmation in a larger controlled study.

 

Prithviraj Bose, Naveen Pemmaraju, Naval Daver, Elias Jabbour, et al. 

SOTATERCEPT (ACE-011) IN SUBJECTS WITH MPN-ASSOCIATED MYELOFIBROSIS AND ANEMIA

Conclusion: Sotatercept improves anemia of MF, both when given alone and in subjects receiving rux.

 

Deepti Radia, Michael W. Deininger, Jason Gotlib, Prithviraj Bose, et al.

AVAPRITINIB, A POTENT AND SELECTIVE INHIBITOR OF KIT D816V, INDUCES COMPLETE AND DURABLE RESPONSES IN PATIENTS (PTS) WITH ADVANCED SYSTEMIC MASTOCYTOSIS (ADVSM)

Conclusion: Avapritinib has shown high activity with durable responses in this Phase 1 study, and median OS was not reached in AdvSM, including in those with MCL, prior midostaurin treatment, and S/A/R high molecular risk genotype. These findings support continued evaluation of avapritinib across the spectrum of AdvSM.

 

Ronald Hoffman, John Mascarenhas, Marina Kremyanskaya, Prithviraj Bose, et al. 

CPI-0610, A BROMODOMAIN AND EXTRATERMINAL DOMAIN (BET) INHIBITOR, REDUCES PRO-INFLAMMATORY CYTOKINES, BONE MARROW FIBROSIS AND THE NUMBER OF TRANSFUSIONS IN MYELOFIBROSIS PATIENTS

Conclusion: CPI-0610 alone or in combination with Rux demonstrates encouraging clinical activity (spleen responses, conversion to TI and improvement in BM fibrosis) with good tolerability. Assessment of CK levels suggest that CPI-0610 therapy durably reduces pro-inflammatory CK. Notably, levels of individual CK were reduced to levels observed in normal healthy donors and were maintained during treatment. Genomic profiling data shows that majority of pts had HMR MUT at baseline. Updated data will be presented.

 

Kristen Pettit, Natasha Curtin, Maciej Tartaczuch, Jake Shortt, et al.

A PHASE 2A STUDY OF THE LSD1 INHIBITOR IMG-7289 FOR THE TREATMENT OF MYELOFIBROSIS

Conclusion: This is the first report of the clinical use of an LSD1 inhibitor for MPNs.  IMG-7289 was well-tolerated in a heterogeneous population of patients with MF and limited therapeutic options.  IMG-7289 was effective in reducing spleen volumes and substantially improved symptom scores in a majority of patients.  On the basis of these results, this study has expanded into a Phase 2b trial to include EU and UK sites now open for enrollment.