An Extension Study of Bomedemstat (IMG-7289/MK-3543) in Participants With Myeloproliferative Neoplasms (IMG-7289-CTP-202/MK-3543-005)

A Multi-Center, Open Label, Extension Study Evaluating the Safety and Efficacy of Bomedemstat for the Treatment of Patients With Myeloproliferative Neoplasms (MPNs) Enrolled in a Prior Bomedemstat Clinical Study

This is a multi-center, open-label extension study to assess the long-term safety and efficacy of bomedemstat administered orally once daily in participants with a Myeloproliferative Neoplasm (MPN) who participated in a prior bomedemstat study such as, but not limited to, IMG-7289-CTP-102/MK-3543-002 (NCT03136185) and IMG-7289-CTP-201/MK-3543-003 (NCT04254978) (referred to hereafter as 'feeder studies').

Inclusion Criteria:

Inclusion Criteria include, but are not limited to:

• Has completed at least one Treatment Period (TP) in a prior bomedemstat Myeloproliferative Neoplasms (MPN) protocol (such as, but not limited to, IMG-7289-CTP-102/MK-3543-002 (NCT03136185) and IMG-7289-CTP-201/MK-3543-003) (NCT04254978).
• In the estimation of the Investigator, the risk-benefit favors continued dosing with bomedemstat.

Exclusion Criteria:

Exclusion Criteria include, but are not limited to:

• Ongoing participation in another investigational study (except observational studies).
• A history of non-compliance in a prior bomedemstat study (excluding dose suspensions that were medically warranted).
• Current use of a prohibited medication (e.g., romiplostim).
• Medical, psychiatric, cognitive, or other conditions that, in the Investigator's opinion, compromise the patient's safety, ability to give informed consent, or comply with the trial protocol.
• Is pregnant or breastfeeding or plan to become pregnant or breastfeed during the study.
• Women of childbearing potential (WOCBP) and fertile men unwilling to agree to use an approved method of contraception from time of enrollment until 14 days after last bomedemstat dose.