Incyte Corporation (Nasdaq: INCY) today announced results from two ongoing clinical trials of Jakafi
(ruxolitinib), an oral JAK1 and JAK2 inhibitor that is FDA-approved for the treatment of patients with intermediate or high-risk myelofibrosis (MF), that were presented at the 18
Congress of the European Hematology Association (EHA) in Stockholm, Sweden. In a three-year follow-up analysis of the Phase III COMFORT-II study, treatment with Jakafi, which is marketed as Jakavi
by Novartis outside the United States, was associated with improved overall survival and sustained reductions in spleen size compared to best available therapy. In a separate exploratory analysis of bone marrow fibrosis data from an ongoing Phase I/II single-arm, open-label clinical trial, by 48 months of treatment, Jakafi stabilized or reversed fibrosis of the bone marrow in 56 percent and 22 percent, respectively, of patients with MF, a magnitude of an effect not seen historically with best available therapy.
“Results of these studies represent the continuing evolution in our understanding of the clinical benefits of Jakafi for patients with intermediate or high-risk myelofibrosis and further support my confidence that long-term treatment with Jakafi may modify this progressive and life-threatening blood cancer,” stated Srdan Verstovsek, M.D., Ph.D., Professor, Department of Leukemia, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center in Houston.
“Data from the Phase I/II study provide the first evidence that long-term treatment with Jakafi may stabilize or improve bone marrow fibrosis, a key marker of worsening disease in patients with myelofibrosis. These findings, in addition to what was presented at ASCO, provide a result not seen before with best available therapy, including hydroxyurea. Future studies should improve our understanding of the significance of these findings,” stated presenting author Hans Michael Kvasnicka, M.D., of the University of Frankfurt in Germany.
Long-Term Outcomes from a Phase III Study Comparing Ruxolitinib with Best Available Therapy for the Treatment of Myelofibrosis: A 3-Year Update of COMFORT-II
In a three-year follow-up analysis of the COMFORT-II study, an overall survival advantage was observed in patients treated with Jakafi compared to patients receiving best available therapy. A 52 percent reduction in risk of death was observed in the Jakafi arm compared with best available therapy (HR=0.48; 95% CI, 0.28-0.85; p=0.009)
, and the estimated probability of overall survival was significantly greater with Jakafi compared to best available therapy (81 percent compared to 61 percent, respectively) at 144 weeks. Additionally, 51.4 percent of patients treated with Jakafi achieved a ≥35 percent reduction from baseline in spleen size over the course of the study. Spleen response was maintained, with the median duration of this response not yet reached in the study.
Anemia and thrombocytopenia were the most common adverse events over the three-year follow-up; however, the rates of these events decreased over time. Among patients randomized to Jakafi and included in the extension phase, the general frequency of the most common non-hematologic adverse events (peripheral edema, diarrhea and asthenia) did not change over time.