KSQ Therapeutics

KSQ Therapeutics, Inc. is a clinical-stage biotechnology company developing treatments for solid tumors. Its core discovery engine, branded CRISPRomics, industrializes genome-wide CRISPR/Cas9 functional genomic screens across a range of cancer models and immune cell types in order to identify therapeutic targets. The company states it also uses an in vivo CRISPR2 screening approach to identify combinations of gene targets. Screening outputs are translated into two therapeutic modalities: autologous engineered tumor-infiltrating lymphocyte (eTIL) cell therapies and partnered small-molecule candidates.

The eTIL approach knocks out CRISPRomics-identified targets SOCS1 and Regnase-1 in patient-derived tumor-infiltrating lymphocytes, which the company says boosts T cell infiltration and tumor-killing in animal models. Lead program KSQ-001EX is a single-edit (SOCS1-inactivated) eTIL therapy manufactured with the company's ExPRESS process and is in an open-label Phase 1/2 safety lead-in study (NCT06237881) in melanoma, head and neck squamous cell carcinoma and non-small cell lung cancer, with a cohort dosed without IL-2. KSQ-004EX is a dual-edit (SOCS1 and Regnase-1) eTIL therapy in a Phase 1/2 study (NCT06598371) spanning melanoma, HNSCC, NSCLC, colorectal, pancreatic and cervical cancers. KSQ-4279 (RO7623066/RG6614) is a first-in-class small-molecule inhibitor of USP1, a regulator of the DNA damage response, studied in a Phase 1 trial in advanced solid tumors (NCT05240898) and licensed worldwide to Roche in July 2023; KSQ says it is exploring additional indications for the asset.

The company frames the market opportunity around the statement that solid tumors account for 90% of cancer cases and that more than 600,000 people die of cancer annually in the U.S., and notes that the first TIL therapy has been approved in the U.S. for melanoma but falls short for many patients.

Founding story

KSQ was founded in 2015 by David Sabatini of the Whitehead Institute and MIT, William Hahn of the Broad Institute and Dana-Farber Cancer Institute, Jonathan Weissman of the UCSF School of Medicine, and Tim Wang of MIT, with Flagship Pioneering and Polaris Partners as founding investors. The premise was to use gene editing to interrogate the entire genome and pinpoint which of the roughly 20,000 human genes make the best drug targets in cancer and immune dysfunction.

Business model

KSQ develops proprietary therapeutic candidates in-house while monetizing platform-derived assets through out-licensing and pharmaceutical collaborations. Its chief business officer is described as having led three major transactions with Ono, Takeda and Roche that extended the company's runway and gave partners access to KSQ discoveries.

Non-commercial; the company reports no marketed products. Disclosed sources of capital are venture financing and license/collaboration agreements with pharmaceutical partners, including the worldwide license and collaboration agreement with Roche for KSQ-4279 entered in July 2023.

Traction

FDA cleared INDs for KSQ-001EX (announced November 2023) and KSQ-004EX (September 2024); the first patient was dosed in the KSQ-004EX Phase 1/2 study in April 2025. First-in-human Phase 1 results for KSQ-001EX were presented as an oral presentation at AACR in April 2026. KSQ-4279 completed a Phase 1 trial in advanced solid tumors and is partnered with Roche. The company reported more than 70 employees in September 2018; a third-party directory listed approximately 60 employees as of July 2026.

Latest developments

In April 2025 KSQ announced the first patient dosed in the Phase 1/2 study of KSQ-004EX. In 2025 and 2026 the company presented data at SITC and AACR, including first-in-human Phase 1 results for KSQ-001EX and preclinical eCAR-T work applying dual SOCS1/Regnase-1 editing to CAR-T cells, and published in Frontiers in Immunology in 2026. It states it is exploring additional indications for KSQ-4279.