Ropeginterferon-α2b discontinuation after long-term exposure: four cases from a single institution

Area of Science:

• Hematology
• Oncology
• Pharmacology

Background:

• Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by excessive blood cell production.
• JAK2 mutations, particularly JAK2V617F, are the primary drivers of PV.
• Ropeginterferon-α-2b (RopegIFN) is an effective therapy for PV, reducing JAK2V617F allele burden and achieving complete hematologic response (CHR).

Purpose of the Study:

• To evaluate the outcomes of patients with polycythemia vera (PV) who discontinued Ropeginterferon-α-2b (RopegIFN) after achieving complete hematologic response (CHR).
• To assess the durability of remission and the potential for sustained molecular response after treatment cessation.

Main Methods:

• Case series of four patients with PV who achieved CHR on RopegIFN and subsequently discontinued therapy.
• Monitoring of hematologic parameters and JAK2V617F allele burden post-discontinuation.

Main Results:

• One patient achieved sustained long-term remission with a JAK2V617F allele burden below 10%, meeting criteria for "operational cure."
• Three patients experienced relapse with rising blood counts and loss of CHR after discontinuing RopegIFN.
• A robust molecular response appeared crucial for predicting sustainable remission.

Conclusions:

• Discontinuation of RopegIFN after achieving CHR in PV carries a significant risk of relapse for most patients.
• Continuous therapy with RopegIFN remains the standard of care due to the absence of reliable predictive models for safe treatment cessation.
• Further research is needed to determine if patients achieving an "operational cure" can remain treatment-free.