CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Syros Pharmaceuticals (NASDAQ: SYRS), a leader in the development of medicines that control the expression of genes, today announced that the first patient has been dosed in the Phase 1 clinical trial of SY-5609, its highly selective and potent oral cyclin-dependent kinase 7 (CDK7) inhibitor. The trial is enrolling patients with advanced breast, colorectal, lung or ovarian cancer, or with solid tumors of any histology that harbor Rb pathway alterations.

“SY-5609 represents a promising new approach for treating a number of cancers that have eluded treatment with other targeted approaches,” said Kyriakos P. Papadopoulos, M.D., Co-Director of Clinical Research at South Texas Accelerated Research Therapeutics (START), and a clinical investigator in the trial. “We are always looking for opportunities to accelerate the development of new treatments to improve patients’ lives and give them real hope against cancer. SY-5609 has demonstrated compelling preclinical activity in a range of cancer models, and we are excited to further investigate it in this Phase 1 study.”

SY-5609 has shown substantial anti-tumor activity, including complete regressions, in multiple preclinical models of solid tumors, including breast, colorectal, lung and ovarian cancers, at doses below the maximum tolerated dose (MTD). In preclinical studies of breast, lung and ovarian cancers, deeper and more sustained responses were associated with the presence of Rb pathway alterations. SY-5609 has also shown anti-tumor activity in combination with fulvestrant in treatment-resistant models of estrogen receptor-positive breast cancer, including those resistant to both fulvestrant and a CDK4/6 inhibitor.

“SY-5609 is a potentially transformative targeted approach for a range of difficult-to-treat cancers,” said David A. Roth, M.D., Chief Medical Officer of Syros. “CDK7 inhibition attacks two fundamental processes in cancer: increased expression of cancer-driving genes, and uncontrolled cell cycle progression. Based on this dual mechanism and the exquisite selectivity and preclinical potency of SY-5609, we believe it could provide a profound benefit for patients in dire need of new therapies. We have designed our Phase 1 trial to move efficiently through dose escalation and to increase the chances of seeing early signals of clinical activity by focusing on patient populations we believe are most likely to respond.”

The Phase 1 trial is a multi-center, open-label, dose-escalation trial that is expected to enroll approximately 60 patients with advanced breast, colorectal, lung or ovarian cancer, or with solid tumors of any histology that harbor Rb pathway alterations. The primary objectives of the dose escalation are to assess the safety and tolerability of escalating doses of SY-5609, with the goal of establishing an MTD. Additional objectives include assessments of anti-tumor activity, pharmacokinetics (PK), pharmacodynamics (PD) and potential predictive biomarkers, including Rb pathway alterations. In a future expansion portion of the Phase 1 trial, multiple cohorts are planned to further evaluate the safety and anti-tumor activity of SY-5609 as both a single agent and in combination with other therapies.

Syros expects to report initial safety, tolerability and PK/PD data in the fourth quarter of 2020 and additional dose-escalation data, including clinical activity, in mid-2021.

About Syros Pharmaceuticals
Syros is redefining the power of small molecules to control the expression of genes. Based on its unique ability to elucidate regulatory regions of the genome, Syros aims to develop medicines that provide a profound benefit for patients with diseases that have eluded other genomics-based approaches. Syros is advancing a robust pipeline, including SY-1425, a first-in-class oral selective RARα agonist in a Phase 2 trial in a genomically defined subset of acute myeloid leukemia patients, and SY-5609, a highly selective and potent oral CDK7 inhibitor in a Phase 1 trial in patients with select solid tumors. Syros also has multiple preclinical and discovery programs in oncology and monogenic diseases. For more information, visit and follow us on Twitter (@SyrosPharma) and LinkedIn.

Cautionary Note Regarding Forward-Looking Statements
This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995, including without limitation statements regarding the timing for reporting data from the Phase 1 clinical trial of SY-5609, the ability to see signals of clinical activity in such trial, the future expansion of such trial, and the ability of SY-5609 to have a benefit for patients. The words ‘‘anticipate,’’ ‘‘believe,’’ ‘‘continue,’’ ‘‘could,’’ ‘‘estimate,’’ ‘‘expect,’’ “hope,” ‘‘intend,’’ ‘‘may,’’ ‘‘plan,’’ ‘‘potential,’’ ‘‘predict,’’ ‘‘project,’’ ‘‘target,’’ ‘‘should,’’ ‘‘would,’’ and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various important factors, including Syros’ ability to: advance the development of SY-5609 under the timelines it projects in current and future clinical trials; demonstrate in any current and future clinical trials the requisite safety, efficacy and combinability of SY-5609; replicate scientific and non-clinical data in clinical trials; successfully establish a patient selection strategy and develop a companion diagnostic test to identify patients most likely to benefit from SY-5609; obtain and maintain patent protection for its drug candidates and the freedom to operate under third party intellectual property; obtain and maintain necessary regulatory approvals; identify, enter into and maintain collaboration agreements with third parties; manage competition; manage expenses; raise the substantial additional capital needed to achieve its business objectives; attract and retain qualified personnel; and successfully execute on its business strategies; risks described under the caption “Risk Factors” in Syros’ Annual Report on Form 10-K for the year ended December 31, 2018 and Quarterly Report on Form 10-Q for the quarter ended September 30, 2019, each of which is on file with the Securities and Exchange Commission; and risks described in other filings that Syros makes with the Securities and Exchange Commission in the future. Any forward-looking statements contained in this press release speak only as of the date hereof, and Syros expressly disclaims any obligation to update any forward-looking statements, whether because of new information, future events or otherwise.

Media Contact:
Naomi Aoki
Syros Pharmaceuticals, Inc.

Investor Contact:
Hannah Deresiewicz
Stern Investor Relations, Inc.

Source: Syros Pharmaceuticals