CART Cell Cancer Immunotherapy
Credit: Juan Gaertner/Science Photo Library/Getty Images

Clasp Therapeutics, which advances precision immuno-oncology using next-generation T cell engagers (TCEs), launched this week with $150 million in financing. The company’s “next-gen” TCEs, they say, can target common oncogenic mutations with greater specificity. The round was led by Catalio Capital Management, Third Rock Ventures, and Novo Holdings.

Clasp’s scientific founders include renowned cancer geneticist and HHMI investigator Bert Vogelstein, MD, and immuno-oncology pioneer Drew Pardoll, MD, PhD, both of Johns Hopkins University. “These researchers’ structure-driven understanding of human leukocyte antigen (HLA)-antibody interactions enables the engineering of advanced TCEs that can precisely target common oncogenic mutations with exquisite specificity,” according to the press release.

Other funders in this round included Vivo Capital, Cure Ventures, Blackbird BioVentures, Pictet Alternative Advisors, American Cancer Society’s Bright Edge and Alexandria Venture Investments. 

Clasp’s modular TCEs are tailored to each patient’s immune system and directed to common oncogenic driver mutations. The company says this platform allows them to create off-the-shelf, antibody-like treatments that can specifically target a wide variety of hard-to-treat tumor types.

“At Clasp we strive to help people with cancer lead longer and healthier lives by engaging each patient’s own immune cells to eradicate their cancer with absolute specificity,” said CEO Robert Ross, MD, “Clasp brings together leading researchers, clinicians and drug developers to develop groundbreaking cancer immunotherapies that are precise and potent, but without the toxicities commonly associated with on-target, off-tumor binding.”

“We have the ability to redirect T cells to kill cancer cells while sparing healthy cells throughout the body,” said Andrea Van Elsas, PhD, partner at Third Rock Ventures and CSO at Clasp. “Clasp’s proprietary technology enables immune targeting of intracellular oncogenic driver mutations to achieve durable tumor killing, even with low levels of surface presentation. Furthermore, the modularity of Clasp’s TCE platform gives it potential to address unmet needs across a broad range of hard-to-treat tumor types.”

Clasp’s TCEs are bispecific antibody-like molecules designed to simultaneously bind both a T cell and a tumor-specific mutant peptide, presented in the context of the patient’s HLA immune signature. A key aspect of this approach is Clasp’s ability to select patients for treatment by focusing on common tumor-specific driver mutations, including many that are unresponsive to standard immunotherapies. By binding both the T cell and the tumor cell with absolute specificity, the company says. This approach ensures immune activation against the tumor itself while sparing normal tissue, which lacks the tumor-specific mutated peptide.

“Clasp’s novel technology has tremendous potential to help the many cancer patients who are unable to benefit from existing treatments,” said Jacob Vogelstein, PhD, and George Petrocheilos, managing partners of Catalio Capital Management. 

Clasp says it is, “… pioneering precision in immuno-oncology through next-generation T cell engagers (TCEs) that target tumor-specific oncogenic driver mutations common across hard-to-treat cancers.” The company identifies mutation-associated neoantigens and develops TCEs that can selectively bind HLA (human leukocyte antigen)-presented peptides derived from these oncogenic drivers. 

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