Essential Thrombocythemia Trial Launched Evaluating Bomedemstat

A second phase 3 clinical trial has been launched for the investigational oral drug bomedemstat as a potential new treatment for patients with essential thrombocythemia.

The Shorespan-007 clinical trial, according to a news release from bomedemstat manufacturer Merck, will investigate the use of the drug among patients with essential thrombocythemia who have not previously received cytoreductive therapy.

The global trial, which is currently recruiting, will compare bomedemstat to the current standard of care chemotherapy, hydroxyurea. The trial, with 300 participants, is expected to be concluded in May 2029, according to its listing on clinicaltrials.gov.

Essential thrombocythemia, part of a group of blood cancers known as myeloproliferative neoplasms (MPNs), is a rare disease in which the bone marrow produces too many platelets, according to The Leukemia & Lymphoma Society. This disease, The Leukemia & Lymphoma Society explained, can cause blood clots to form in a patient’s blood vessels, in turn resulting in serious health issues such as stroke, heart attack or pulmonary embolism.

LEARN MORE: Educated Patient MPN Summit Essential Thrombocythemia Panel

“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 Dr. Gregory Lubiniecki, vice president of global clinical development for Merck Research Laboratories, in the company’s news 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 study will be assessing patients’ responses to treatment as well as fatigue, patient-reported outcomes, duration of remission, event-free survival (the time a patient lives without complications from their disease) and disease progression rate, according to the news release.

Bomedemstat, according to the National Cancer Institute, is intended to inhibit cell growth among tumor cells that overexpress LSD1, an enzyme that plays a key role in regulating gene expression, tumor cell growth and survival.

During a CURE® Educated Patient Summit in 2022, Dr. Douglas A. Tremblay, assistant professor of medicine at the Icahn School of Medicine at Mount Sinai in New York City, noted that bomedemstat keeps hemoglobin counts stable in patients with essential thrombocythemia, “which is unique among other cytoreductive therapies which reduce all counts.”

“It also may improve the burden of [essential thrombocythemia]-related symptoms, especially fatigue, that patients with [essential thrombocythemia] can experience,” he added. “And importantly, it does look at the amount of mutation burden that someone has, which we think may be a surrogate for progression, although it hasn’t fully been established.”

In addition to Shorespan-007, bomedemstat is also being investigated in the phase 3 global Shorespan-006 clinical trial evaluating the drug versus best available therapy among patients with essential thrombocythemia who have inadequate response to or intolerant of hydroxyurea, Merck stated in the news release. That trial, which is currently recruiting, will have 300 patients and is estimated to be completed in August 2028, according to its listing on clinicaltrials.gov.

The Food and Drug Administration has granted bomedemstat Orphan Drug and Fast Track designations for the treatment of essential thrombocythemia and myelofibrosis, as well as an Orphan Drug Designation for acute myeloid leukemia.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.