Highlights of Key Data Presented
- Verstovsek, S, et al. Long-term outcome of ruxolitinib treatment in patients with myelofibrosis: Durable reductions in spleen volume, improvements in quality of life, and overall survival advantage in COMFORT-I.
- Cervantes, F, et al. Long-term safety, efficacy, and survival findings from COMFORT-II, a Phase III study comparing ruxolitinib with best available therapy for the treatment of myelofibrosis.
In two Phase III randomized clinical studies, COMFORT-I and COMFORT-II, Jakafi was associated with a survival advantage over placebo and best available therapy, respectively. In COMFORT-I, reductions in spleen volume continued to be observed over two years of treatment. Spleen volume was reduced by 32 percent at week 24 with Jakafi treatment, and this reduction was sustained through week 96. Improvements in quality of life measures also continued to be observed over two years of treatment. Additionally, rates of grade 3 or 4 anemia and thrombocytopenia decreased with long-term therapy, and there was no apparent change in the frequency or severity of non-hematologic adverse events.
Survival analyses were conducted at a two-year follow-up in COMFORT-I and COMFORT-II, comparing patients randomized to Jakafi with those randomized to placebo and best available therapy, respectively. In COMFORT-I, Jakafi continued to be associated with a survival advantage over placebo. There were 27 deaths in the group treated with Jakafi, and 41 in the placebo group, representing a HR=0.58 (95% CI, 0.36-0.95; P = 0.028). Overall survival favored treatment with Jakafi regardless of JAK2V617F mutation status. Similarly, an updated analysis of COMFORT-II suggested longer survival for patients randomized to Jakafi when compared to those randomized to best available therapy. In this study, where twice as many patients were randomized to Jakafi (146) as to placebo (73), there were 14 percent (n=20) deaths in the group treated with Jakafi and 22 percent (n=16) in the best available therapy group, representing a HR=0.51 (95% CI, 0.26-0.99; P = 0.041). These survival benefits were observed even though all patients in the placebo and best available therapy groups continuing in the COMFORT studies were switched to Jakafi treatment soon after the primary analyses, suggesting that earlier initiation of treatment with Jakafi may have contributed to longer survival.