Cyteir Therapeutics Secures $40.2M Series B Financing to Advance RAD51 Inhibitor CYT-0851 for Cancer Therapy

On October 22, 2019, VCBeat (WeChat ID: vcbeat) learned from foreign media reports that biopharmaceutical company Cyteir Therapeutics (“Cyteir”) announced the completion of a $40.2 million Series B financing round. The round was led by Novo Holdings, with participation from Venrock, DROIA Oncology Ventures, Osage University Partners (OUP), Lightstone Ventures, and Celgene.

Cyteir plans to use the proceeds from this financing round to conduct clinical studies on its DNA repair protein inhibitor, CYT-0851, and to identify new targets for inhibiting DNA damage repair. Additionally, Dr. Karen Hong, a consulting expert at Novo Holdings, will join Cyteir’s Board of Directors.

To date, Cyteir has completed four rounds of financing, raising a total of $76.7 million. Among these, the company closed its $29 million Series B round in March 2018 and its $5.5 million Series A round in November 2015.

Cyteir, founded in 2012 and headquartered in Massachusetts, USA, is a biotechnology and pharmaceutical company. The company is a pioneer in the field of DNA damage repair, focusing on the development of next-generation synthetic lethality therapies for various solid tumors. Currently, Cyteir has secured support from leading healthcare investors, including Novo Holdings, Celgene, and Lightstone Ventures.

Cyteir’s R&D team focuses primarily on cytidine deaminase (CD), a DNA-damaging enzyme identified in the salvage pathway of nucleotide metabolism in Escherichia coli, which is found exclusively in bacteria and fungi. This enzyme is harmless to healthy tissues but is overexpressed in various cancer cells, where it inhibits the activity of the DNA repair protein RAD51, thereby causing extensive DNA damage in cancer cells.

Cyteir Therapeutics is developing CYT-0851, a selective small-molecule oral inhibitor targeting CDK enzymes, to impair the ability of cancer cells to self-repair via homologous recombination and thereby promote cancer cell death. In preclinical models, CYT-0851 inhibits RAD51 protein activity by inducing CDK enzyme inhibition, thus blocking cancer cell proliferation. The drug demonstrates efficacy comparable to that of PARP inhibitors, a class of anticancer agents, and holds potential to overcome resistance to PARP inhibitors, making it suitable for treating cancers sensitive to high levels of CDK enzymes.

Preclinical data indicate that CYT-0851 can serve as a monotherapy for B-cell lymphoma and various solid tumors, including pancreatic cancer. Currently, Cyteir has enrolled 200 patients with malignant tumors in a planned Phase 1/2 clinical trial of CYT-0851. The study will be conducted at the Sarah Cannon Research Institute (SCRI), a leading clinical trial site in the United States.

Dr. Markus Renschler, President and Chief Executive Officer of Cyteir, stated, “The strong support from investors reflects the potential of our candidate products. This financing will be used to support the recently initiated Phase 1/2 clinical study of CYT-0851. We will continue to explore new targets for inhibiting DNA damage repair, providing new treatment options for cancer patients.”

“Dr. Johanna Bendell, Chief Research and Development Officer at SCRI and Principal Investigator of the CYT-0851 clinical study, stated, ‘We are delighted to participate in this study and help Cyteir Therapeutics develop a novel cancer-targeted therapy. The preclinical evaluation results for CYT-0851 are encouraging, and we look forward to observing the efficacy of CYT-0851 in patients in this trial.’”

Novo Holdings, established in 1999 and headquartered in Copenhagen, Denmark, is the venture capital and private equity arm of the Novo Group. With operations in Copenhagen, San Francisco, and Boston, it is a leading global investor in life sciences and healthcare, dedicated to creating long-term value for its portfolio companies.

Venrock, established in 1969 and headquartered in California, United States, is the venture capital arm of the Rockefeller Family. The firm primarily focuses on the biotechnology, healthcare, medical device, and pharmaceutical industries.

DROIA, established in 2011 and headquartered in Luxembourg, Europe, is a venture capital firm dedicated to advancing the field of oncology therapeutics.

OUP, established in 2009 and headquartered in Pennsylvania, USA, is a venture capital firm. The firm primarily invests in startups commercializing academic research achievements, with a focus on the biotechnology, medical device, and pharmaceutical industries.

Lightstone Ventures, founded in 2012 and headquartered in California, USA, is a leading venture capital firm primarily investing in biotechnology, medical devices, and pharmaceuticals.

Celgene, founded in 1986 and headquartered in New Jersey, USA, is a globally leading publicly traded biopharmaceutical company. The company is dedicated to developing and commercializing innovative therapies for cancer and immune-inflammatory diseases, aiming to treat complex, difficult-to-cure conditions such as multiple myeloma (MM) and myelodysplastic syndromes (MDS).

(Compiled by Xu Xiaoxue)