Phase 3 Trial of Bomedemstat in Essential Thrombocythemia Begins Enrollment
The phase 3 Shorespan-007 trial will compare bomedemstat with hydroxyurea in patients with treatment-naive essential thrombocythemia.
Essential thrombocytosis blood smear - ©MdBabul - stock.adobe.comEssential thrombocytosis blood smear - ©MdBabul - stock.adobe.com
A pivotal phase 3 trial (NCT06456346) has initiated to evaluate bomedemstat (MK-3543; IMG-7289), an investigational agent for the treatment of patients with essential thrombocythemia (ET) who have previously not received cytoreductive therapy.1
“The standard of care in essential thrombocythemia has remained unchanged for decades, and patients are in need of new options that have the potential to not only improve disease control, but also improve their quality of life,” said Gregory Lubiniecki, MD, vice president, global clinical development, Merck Research Laboratories, in a press release. “We are rapidly advancing our clinical development programs with the goal of helping to address these unmet needs and bring more options to patients living with myeloproliferative neoplasms.”
The Shorespan-007 trial will compare the orally available LSD1 inhibitor bomedemstat with standard-of-care hydroxyurea in patients with treatment-naive ET, the most common myeloproliferative neoplasm. LSD1 is an enzyme that is potentially important for regulating the proliferation of hematopoietic stem cells, as well as the maturation of progenitor cells.
The study’s primary end point is durable clinicohematologic response rate, and secondary end points include duration of hematologic remission, event-free survival, incidence of adverse events, and disease progression rate. Additionally, investigators will be patient-reported outcomes, including fatigue and symptoms.
The FDA previously granted orphan drug and fast track designations to bomedemstat in ET and myelofibrosis, as well as orphan drug designation in acute myeloid leukemia.
Bomedemstat is also being evaluated in the phase 3 Shorespan-006 trial(NCT06079879). This study is comparing the agent in patients with ET who had an inadequate response to or are intolerant of hydroxyurea. Additional Shorespan studies are investigating bomedemstat in other myeloproliferative neoplasms including myelofibrosis and polycythemia vera.
About Shorespan-007
The phase 3, randomized, double-blind Shorespan-007 study plans to enroll 300 patients globally. Those in the experimental arm will receive bomedemstat and hydroxyurea placebo or hydroxyurea and bomedemstat placebo for up to 52 weeks. Patients who complete 52 weeks of treatment will be eligible to continue in the extended treatment phase.2
To be eligible for enrollment, patients must have a diagnosis of ET based on World Health Organization criteria for myeloproliferative neoplasms with an indication for cytoreductive therapy, a bone marrow fibrosis score of grades 0 or 1, and not received prior cytoreductive treatment. Patients with HIV, hepatitis B, or hepatitis C infections are eligible for participation if the infections are well controlled. Patients with history of gastrointestinal impairment that may affect drug absorption, history of additional malignancies, or an active infection requiring systemic therapy are not eligible for study enrollment.
