Study of TL-895 Combined With Ruxolitinib in JAKi Treatment-Naïve MF Subjects and Subjects With MF Who Have a Suboptimal Response to Ruxolitinib

Inclusion Criteria

• Inclusion Criteria: Subjects with suboptimal response to ruxolitinib: - Treatment with at a stable dose of ruxolitinib prior to study entry - Subjects ≥ 18 years of age and able to provide informed consent. - Confirmed diagnosis of PMF, post-PV MF, or post-ET MF, as assessed by treating physician according to the World Health Organization (WHO) criteria - High-risk, intermediate-2 risk, or intermediate-1 risk, defined by Dynamic International Prognostic System (DIPSS) - Palpable spleen measuring ≥ 5 cm below the left lower coastal margin (LLCM) or spleen volume of ≥ 450 cm3 by MRI or CT scan assessment - Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 - Adequate hematological, hepatic, & renal function. Exclusion Criteria: Treatment-naive subjects: - Prior treatment with any JAKi Subjects with suboptimal response to ruxolitinib: - Documented disease progression while on ruxolitinib treatment All subjects: - Prior splenectomy or splenic irradiation within 24 weeks prior to first dose of study treatment - Prior treatment with a BTK or BMX inhibitor