Trial Expansion Stage Begun for Seclidemstat for Ewing Sarcoma

In a recent press release, biopharmaceutical company Salarius Pharmaceuticals, Inc. (“Salarius”) shared that it had initiated an expansion stage of a Phase 1/2 clinical trial. Within the trial and the expansion, Salarius is evaluating seclidemstat for patients with relapsed and refractory Ewing sarcoma and other related sarcomas. Thus far, seclidemstat received Rare Pediatric Disease, Fast Track, and Orphan Drug designations. If it is shown to be efficacious, it would offer a safe and beneficial treatment option for patients.


In prior research, researchers determined that lysine-specific histone demethylase 1 enzyme (LSD1) plays a role in cancer development. When LSD1 is over-expressed, it allows for the increased proliferation of cancer cells. High LSD1 levels have been associated with small-cell lung cancer (SCLC) and acute myeloid leukemia (AML), for example. Seclidemstat is an orally administered therapy designed to inhibit LSD1.

In the expansion trial, researchers will enroll two separate treatment arms. First, 20 patients with Ewing sarcoma will enroll. Within this treatment arm, patients will receive seclidemstat in conjunction with topotecan and cyclophosphamide. In the second group, 30 patients with related sarcomas will enroll. During this phase, this group will receive the recommended dose of seclidemstat as a singular treatment. Data will be available by the beginning of 2022.

Researchers believe that the first treatment arm could show the safety, efficacy, and tolerability of seclidemstat when used with other treatments. This would allow for more targeted treatment of Ewing sarcoma.

Ewing Sarcoma

Ewing sarcoma, sometimes known as Ewing’s sarcoma, is part of the Ewing family of tumors, which also encompasses peripheral primitive neuroectodermal tumors and extraosseous Ewing tumors. These cancers develop in the bone and surrounding tissue, often in the chest, legs, and pelvis. While Ewing sarcoma can affect those of any age, it often impacts those between ages 10-20. Being male and being Caucasian heighten the risk of developing Ewing sarcoma. An estimated 200-225 children and teens develop Ewing sarcoma in the U.S. each year.

While doctors do not have a definitive cause for Ewing sarcoma, some believe it has a genetic component. Sporadic chromosomal mutations, such as changes to the EWSR1 gene on chromosome 22, may play a role. Symptoms of Ewing sarcoma include, but are not limited to:

  • Fever
  • Appetite loss
  • Unintended weight loss
  • Fatigue
  • Redness, swelling, and pain around the tumor site
  • Numbness and tingling
  • Incontinence (if located around the spinal region)
  • Bone pain that worsens during exercise
Jessica Lynn

Jessica Lynn

Jessica Lynn has an educational background in writing and marketing. She firmly believes in the power of writing in amplifying voices, and looks forward to doing so for the rare disease community.

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