PRIMARY OBJECTIVES:~I. To collect long term safety and tolerability data in patients with myelofibrosis previously treated with ruxolitinib on protocol 2007-0169.~OUTLINE:~Patients continue to receive ruxolitinib orally (PO) once daily (QD) or twice daily (BID). Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. Patients undergo follow-up assessment for safety over 10 minutes every 3 cycles.
This phase II trial studies the long-term side effects of ruxolitinib in treating patients with myelofibrosis. Collecting data about the long-term safety and tolerability of ruxolitinib may better help future patients with myelofibrosis.