CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Syros Pharmaceuticals today announced the results of new preclinical studies in which SY-351, one of its first-in-class selective cyclin-dependent kinase 7 (CDK7) inhibitors, was observed to have significant anti-tumor activity, including inducing and maintaining complete tumor regression, in in vivo models of acute leukemias. These data are being presented at the American Society of Hematology (ASH) Annual Meeting.

“Our CDK7 inhibitor program highlights the power of our gene control platform to selectively target transcription and potentially treat diseases that so far have been underserved by other genomic-based approaches,” said Nancy Simonian, M.D., Chief Executive of Syros. “People with acute leukemias often face a grim prognosis, and there has been little improvement in treatment options for these patients. Using our platform, we have created potent and selective CDK7 inhibitors that have been shown to alter the levels of cancer-contributing genes with the potential to deliver a profound and durable clinical benefit for these patients.”

In the preclinical studies presented at ASH, Syros’ potent and selective CDK7 inhibitor was observed to preferentially kill cancer cells over normal cells and induce tumor regression in patient-derived xenograft models of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). In the in vitro and in vivo studies, SY-351 was observed to induce:

  • Complete tumor regression in 100 percent of mice treated with a 5 mg/kg dose in patient-derived xenograft models of AML and ALL, which was sustained for 30 days following the end of treatment.
  • Rapid induction of cell death in AML and ALL cell lines, killing 75 percent of cancer cells within 48 hours, while inducing little to no cell death in normal cells.
  • Potent and selective inhibition of CDK7, with limited off-target inhibition when profiled across a panel of 468 kinases.
  • Minimal effect on blood cells, including white blood cells, platelets, lymphocytes, neutrophils and reticulocytes, suggesting a more favorable profile than less selective compounds that inhibit multiple members of the CDK family.
  • Significant repression of Myb, a transcription factor known to play a key role in AML.

Certain cancers, including AML, ALL, small cell lung cancer, triple negative breast cancer and MYCN-amplified neuroblastoma, are dependent on high and constant expression of transcription factors for their growth and survival, and have been shown to be particularly sensitive to selective inhibition of CDK7. Syros is developing potent and highly selective CDK7 inhibitors with enhanced drug-like properties over SY-351.

About Syros Pharmaceuticals
Syros Pharmaceuticals is a biopharmaceutical company applying a pioneering approach to discover and develop medicines that control the expression of genes with the aim of treating cancer and other serious diseases. Syros has built a proprietary gene control platform that provides the Company with a unique lens to identify crucial genes that become dysregulated in diseased cells. Syros is leveraging its platform to develop a pipeline of gene control product candidates that it believes will provide a profound and durable benefit for patients. The Company’s scientific founders are world-class leaders in gene control research and translation. Launched by Flagship Ventures and ARCH Venture Partners, Syros Pharmaceuticals is located in Cambridge, Mass.

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Source: Syros Pharmaceuticals