A Randomized, Double-blind, Placebo-controlled Study of the JAK Inhibitor INCB018424 Tablets Administered Orally to Subjects With Primary Myelofibrosis, Post-Polycythemia Vera Myelofibrosis or Post-Essential Thrombocythemia Myelofibrosis

Trial Information

A Randomized, Double-blind, Placebo-controlled Study of the JAK Inhibitor INCB018424 Tablets Administered Orally to Subjects With Primary Myelofibrosis, Post-Polycythemia Vera Myelofibrosis or Post-Essential Thrombocythemia Myelofibrosis

Patients with spleen growth of greater than 25% based on an increase in spleen volume from
Baseline were eligible for early unblinding, and for patients on placebo, crossover to
ruxolitinib prior to the primary study endpoint being reached. If this spleen growth
occurred before Week 24, it must have been accompanied by specific worsening of symptoms,
based on worsening early satiety accompanied by weight loss or worsening pain requiring
daily narcotic use. After Week 24, asymptomatic spleen growth alone was sufficient for early
unblinding and potential crossover. Patients found to have been randomized to ruxolitinib
after early unblinding prior to Week 24 were discontinued.

When half of the patients remaining in the study completed the Week 36 visit and all
patients enrolled completed Week 24 or discontinued, the database was frozen and the primary
analysis was conducted. Once this was complete, all patients were unblinded and patients who
had been randomized to placebo were given the opportunity to crossover to ruxolitinib
treatment, provided hematology laboratory parameters were adequate; Patients receiving
benefit could continue treatment until the later of marketing approval or when the last
randomized patient remaining in the study had completed Week 144 (36 months).