Send to

Choose Destination
Blood. 2019 Aug 8;134(6):525-533. doi: 10.1182/blood.2018893545. Epub 2019 Jun 5.

Oral idasanutlin in patients with polycythemia vera.

Author information

Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY.
Division of Biostatistics, Mayo Clinic, Scottsdale, AZ.
Mays Cancer Center, University of Texas at San Antonio, San Antonio, TX.
Department of Pathology and Tumor Cytogenomics, Icahn School of Medicine at Mount Sinai, New York, NY.
Center for Hematologic Malignancies, Memorial Sloan Kettering, New York, NY; and.
Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY.


A limited number of drugs are available to treat patients with polycythemia vera (PV) and essential thrombocythemia (ET). We attempted to identify alternative agents that may target abnormalities within malignant hematopoietic stem (HSCs) and progenitor cells (HPCs). Previously, MDM2 protein levels were shown to be upregulated in PV/ET CD34+ cells, and exposure to a nutlin, an MDM2 antagonist, induced activation of the TP53 pathway and selective depletion of PV HPCs/HSCs. This anticlonal activity was mediated by upregulation of p53 and potentiated by the addition of interferon-α2a (IFN-α2a). Therefore, we performed an investigator-initiated phase 1 trial of the oral MDM2 antagonist idasanutlin (RG7388; Roche) in patients with high-risk PV/ET for whom at least 1 prior therapy had failed. Patients not attaining at least a partial response by European LeukemiaNet criteria after 6 cycles were then allowed to receive combination therapy with low-dose pegylated IFN-α2a. Thirteen patients with JAK2 V617F+ PV/ET were enrolled, and 12 (PV, n = 11; ET, n = 1) were treated with idasanutlin at 100 and 150 mg daily, respectively, for 5 consecutive days of a 28-day cycle. Idasanutlin was well tolerated; no dose-limiting toxicity was observed, but low-grade gastrointestinal toxicity was common. Overall response rate after 6 cycles was 58% (7 of 12) with idasanutlin monotherapy and 50% (2 of 4) with combination therapy. Median duration of response was 16.8 months (range, 3.5-26.7). Hematologic, symptomatic, pathologic, and molecular responses were observed. These data indicate that idasanutlin is a promising novel agent for PV; it is currently being evaluated in a global phase 2 trial. This trial was registered at as #NCT02407080.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center