Long-term Safety and Efficacy of Momelotinib in Subjects With Primary Myelofibrosis, Post-polycythemia Vera Myelofibrosis, Post-essential Thrombocythemia Myelofibrosis, Polycythemia Vera or Essential Thrombocythemia

Open-label Study to Assess the Long-term Safety and Efficacy of Momelotinib in Subjects With Primary Myelofibrosis, Post-polycythemia Vera Myelofibrosis, Post Essential Thrombocythemia Myelofibrosis, Polycythemia Vera or Essential Thrombocythemia

This open-label study is to determine the long-term safety and tolerability of momelotinib in previously enrolled study participants with primary myelofibrosis (PMF), post-polycythemia vera myelofibrosis (post-PV MF), post-essential thrombocythemia myelofibrosis (post-ET MF), polycythemia vera (PV), or essential thrombocythemia (ET), who have tolerated and achieved stable disease or better with momelotinib treatment while enrolled in a previous clinical trial.

Key Inclusion Criteria:

• Currently enrolled in study CCL09101E, or YM387-II-02, or successfully completed 24 weeks of study GS-US-352-1672
• Able to comprehend and willing to sign informed consent form

Key Exclusion Criteria:

• Known hypersensitivity to momelotinib, its metabolites, or formulation excipients

Note: Other protocol defined Inclusion/Exclusion criteria may apply.