Defining ruxolitinib failure and transition to next-line therapy for patients with myelofibrosis: a modified Delphi panel consensus study.

To define ruxolitinib failure and develop parameters to guide transition to next-line therapy for patients with myelofibrosis. A modified Delphi panel with 14 hematologists-oncologists. Survey concepts included defining primary refractory status, loss of response, disease progression, intolerance and transition to next-line therapy. Ruxolitinib failure may be defined as no improvement in symptoms or spleen size, progressive disease or ruxolitinib intolerance, following a maximally tolerated dose for ≥3 months. Loss of spleen response 1 month after initial response may prompt discontinuation. Lack of evidence to inform transition to next-line therapy was noted; tapering ruxolitinib should be considered according to ruxolitinib dose and patient characteristics. Expert consensus was provided on defining ruxolitinib failure and transition to next-line therapy as summarized in this position paper, which may support considerations in the development of future clinical practice guidelines.