Developmental Therapeutics in Myeloproliferative Neoplasms

Area of Science:

• Hematology
• Oncology
• Pharmacology

Background:

• The Janus kinase (JAK) 1/2 inhibitor ruxolitinib has shown significant success in treating myelofibrosis (MF).
• Ruxolitinib has improved survival, spleen volume, and symptoms in MF patients, establishing it as a cornerstone therapy.
• Despite ruxolitinib's efficacy, significant unmet needs persist in MF treatment, driving the investigation of novel therapeutic agents.

Purpose of the Study:

• To review the current landscape of drug development for Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs).
• To highlight novel therapeutic agents and targets being investigated beyond ruxolitinib.
• To discuss ongoing clinical trials for MF, polycythemia vera (PV), and essential thrombocythemia (ET).

Main Methods:

• Review of current literature and clinical trial data for novel MPN therapies.
• Focus on agents targeting pathways beyond JAK inhibition.
• Discussion of emerging treatments for MF, PV, and ET.

Main Results:

• Numerous novel drug classes are under investigation, including HDAC inhibitors, DNA methyltransferase inhibitors, PI3K inhibitors, HSP90 inhibitors, CDK4/6 inhibitors, and Hedgehog signaling inhibitors.
• Other JAK inhibitors with improved selectivity and reduced myelosuppression are in development.
• First-in-class agents like sotatercept, imetelstat, and PRM-151 are in clinical trials for MF.
• Novel interferon, HDM2 inhibitors, and HDAC inhibitors (e.g., givinostat) show promise for PV.
• Ruxolitinib is approved for second-line PV therapy and is being developed for ET.

Conclusions:

• The development of novel agents for MPNs is rapidly advancing, building upon the success of ruxolitinib.
• Targeted therapies and first-in-class agents offer new hope for patients with unmet needs in MF, PV, and ET.
• Continued research and clinical trials are crucial for optimizing MPN treatment strategies.