An analysis of 5-year data from two large clinical trials provide further support that treatment with Jakafi® (ruxolitinib) improves long-term survival, compared to other treatment options for patients with myelofibrosis. Importantly, the data also suggested that treatment with ruxolitinib earlier in the course of a patient’s disease appears to provide a survival advantage over starting treatment with ruxolitnib at a later point in the disease. These results were recently presented at the 2016 annual meeting of the American Society of Hematolog (ASH).
Myelofibrosis (MF) is a type of blood cancer known as a myeloproliferative neoplasm that is chronic and progressive in nature. It involves the abnormal development and function of bone marrow cells that produce blood cells, and leads to the formation of scar tissue in the bone marrow. When the bone marrow becomes scarred, it is not able to produce adequate amounts of blood cells.
Myelofibrosis can cause anemia, enlargement of the spleen and liver, fatigue, and other problems. In some patients with MF, the condition progresses to acute myeloid leukemia, which is an aggressive type of leukemia. Myelofibrosis is rare and affects ~18,000 people in the U. S. Although it can occur at any age, it most commonly occurs in individuals over 65.
When MF develops on its own (and not as the result of another bone marrow disease), it’s called primary myelofibrosis. Myelofibrosis can also result from a worsening of other bone marrow diseases, such as polycythemia vera and essential thrombocythemia.
The JAK1/JAK2 cellular pathway has demonstrated activity involved in the progression of MF. Subsequently, researchers have developed agents, such as ruxolitinib, that block the activity of the JAK1/JAK2 pathway, reducing or halting the negative effects caused by its activity.
Researchers recently analyzed data from two large clinical trials, referred to as the COMFORT-I and COMFORT-II trials that included 301 patients with MF. Patients in the trials were treated with either best available treatment (BAT) according to their healthcare provider, placebo (inactive substitute), or ruxolitinib. Patients who experienced cancer progression while on BAT or placebo were allowed to begin treatment with ruxolitinib.
Patients were followed for approximately 5 years following initiation of therapy.
- Median overall survival time was 5.3 years for patients treated with ruxolitinib, compared with 3.8 years for patients treated with BAT or receiving placebo.
- The survival advantage achieved with ruxolitinib was greater among patients who were initially treated with ruxolitinib, compared with those who initially received BAT or placebo, and began treatment with ruxolitinib after progression of their disease. Median overall survival time was 5.3 years among patients initially treated with ruxolitinib, compared with only 2.3 years for patients initially receiving BAT or placebo.
- Subgroup analysis revealed that patients with certain characteristics have improved responses to ruxolitinib.
The researchers concluded that overall survival at 5 years is improved with treatment including ruxolitinib compared to BAT or placebo, which appears most pronounced among patients treated with ruxolitinib as initial therapy, compared to later in their disease course.
Reference: Incyte News. Pooled Analysis of Five-Year Data from Two Phase 3 Studies Further Supports Overall Survival Advantage Observed in Patients with Myelofibrosis Treated With Jakafi® (ruxolitinib). Available at: http://www.incyte.com/media/recent-news.aspx.