Nurix Therapeutics Announces First Patient Enrolled in Registrational Phase 3 DAYBreak CLL-306 Trial of Bexobrutideg in Relapsed/Refractory Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma

Phase 3 trial designed to demonstrate superiority of bexobrutideg versus pirtobrutinib in patients with relapsed/refractory CLL/SLL previously treated with a covalent BTK inhibitor

BRISBANE, Calif., Aug. 04, 2026 (GLOBE NEWSWIRE) -- Nurix Therapeutics, Inc. (Nasdaq: NRIX) today announced that the first patient has been enrolled in the global Phase 3 DAYBreak CLL-306 study (NCT07516093) evaluating bexobrutideg, a potential best-in-class targeted protein degrader of Bruton’s tyrosine kinase (BTK), in patients with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who have previously received a covalent BTK inhibitor. The global study is being conducted under the collaboration between Nurix and Roche and marks the first Phase 3 trial for bexobrutideg. The registrational study is designed to demonstrate the superiority of bexobrutideg versus the non-covalent BTK inhibitor pirtobrutinib, the current standard of care in this treatment setting for patients whose disease has progressed following prior covalent BTK inhibitor therapy.

"This is an important milestone for the global bexobrutideg development program with the potential to redefine the treatment landscape for patients with CLL through a head-to-head comparison of BTK degradation versus non-covalent inhibition," said Arthur T. Sands, M.D., Ph.D., president and chief executive officer of Nurix. "We believe targeted protein degradation offers a fundamentally differentiated approach to addressing disease targets as compared to traditional small molecule inhibition, and this trial is designed to test whether that differentiation translates into superior outcomes for patients. Together with Roche, we are committed to advancing an ambitious global development program intended to fully realize the potential of BTK degradation across oncology, immunology and neurology."

The randomized Phase 3 trial is expected to enroll approximately 620 patients with relapsed/refractory CLL/SLL who have previously progressed on a covalent BTK inhibitor. Patients will be randomized 1:1 to receive either bexobrutideg 600 mg orally once per day or pirtobrutinib. The dual primary endpoints are objective response rate (ORR) and progression free survival (PFS), as assessed by an independent review committee. The study is designed to evaluate the potential superiority of bexobrutideg relative to pirtobrutinib and support global regulatory submissions.

"Bexobrutideg has demonstrated robust clinical activity in the setting of relapsed/refractory CLL with a favorable safety and tolerability profile," said Paula O'Connor, M.D., chief medical officer of Nurix. "The initiation of DAYBreak CLL-306 reflects our commitment to bringing innovative treatment options to patients with CLL who continue to face significant unmet medical needs."

About Bexobrutideg (NX-5948)
Bexobrutideg (NX-5948) is an investigational, orally bioavailable, brain-penetrant, highly selective small-molecule degrader of Bruton’s tyrosine kinase (BTK) being developed by Nurix and Roche as a potential best-in-class therapy across oncology, immunology and neurology.

​​​Bexobrutideg is currently being evaluated in a broad clinical development program in patients with chronic lymphocytic leukemia (CLL) including the DAYBreak CLL-201 clinical trial (NCT07221500), a pivotal single-arm Phase 2 study in patients with relapsed/refractory CLL, the DAYBreak CLL-306 clinical trial (NCT07516093), a randomized Phase 3 trial comparing bexobrutideg to pirtobrutinib in patients with relapsed/refractory CLL, and the NX-5948-301 Phase 1a/1b clinical trial (NCT05131022) in patients with relapsed/refractory B-cell malignancies. Nurix’s plans also include the NX-5948-203 Phase 1/2 clinical trial (NCT07520006), assessing the combination of bexobrutideg with venetoclax with or without an anti-CD20 antibody in patients with relapsed/refractory CLL and treatment naïve CLL. A new tablet formulation of bexobrutideg is being evaluated in a first-in-human single-ascending-dose and multiple-ascending-dose study in healthy volunteers (NCT06717269) to support future development in immunology and neurology indications. Additional information about these clinical trials can be found at clinicaltrials.gov.

About Nurix Therapeutics
Nurix Therapeutics is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of targeted protein degradation medicines, a new frontier in drug discovery aimed at improving treatment options for patients with cancer and autoimmune diseases. Nurix’s clinical stage oncology pipeline includes bexobrutideg, a degrader of Bruton’s tyrosine kinase (BTK), being co-developed in collaboration with Roche, and NX-1607, an inhibitor of Casitas B-lineage lymphoma proto-oncogene B (CBL-B), an E3 ligase that regulates activation of multiple immune cell types including T cells and NK cells. Nurix's autoimmune disease pipeline includes bexobrutideg, being developed in collaboration with Roche; a clinical-stage IRAK4 degrader, being developed in collaboration with Gilead; and a preclinical-stage STAT6 degrader, being developed in collaboration with Sanofi. Nurix is also advancing multiple potentially first-in-class or best-in-class degraders and degrader antibody conjugates (DACs) in its wholly owned preclinical pipeline as well as those under collaboration agreements with Gilead Sciences, Inc., Sanofi S.A. and Pfizer Inc., within which Nurix retains certain options for co-development, co-commercialization and profit sharing in the United States. Powered by an AI-integrated discovery engine capable of tackling virtually any protein class, and coupled with unparalleled ligase expertise, Nurix’s dedicated team has built a formidable advantage in translating the science of targeted protein degradation into clinical advancements. Nurix aims to establish degrader-based treatments at the forefront of patient care. Nurix is headquartered in Brisbane, California. For additional information visit http://www.nurixtx.com.

Forward-Looking Statements 
This press release contains statements that relate to future events and expectations and as such constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. When or if used in this press release, the words “anticipate,” “believe,” “could,” “estimate,” “expect,” “intend,” “may,” “outlook,” “plan,” “predict,” “should,” “will,” and similar expressions and their variants, as they relate to Nurix, may identify forward-looking statements. All statements that reflect Nurix’s expectations, assumptions or projections about the future, other than statements of historical fact, are forward-looking statements, including, without limitation, statements regarding Nurix’s plans and expectations for the development of bexobrutideg and the potential of targeted protein degradation therapies to address disease. Forward-looking statements reflect Nurix’s current beliefs, expectations, and assumptions. Although Nurix believes the expectations and assumptions reflected in such forward-looking statements are reasonable, Nurix can give no assurance that they will prove to be correct. Forward-looking statements are not guarantees of future performance and are subject to risks, uncertainties and changes in circumstances that are difficult to predict, which could cause Nurix’s actual activities and results to differ materially from those expressed in any forward-looking statement. Such risks and uncertainties include, but are not limited to: (i) whether Nurix and Roche will be able to successfully conduct and complete clinical development of bexobrutideg pursuant to the Nurix-Roche collaboration; (ii) the unexpected emergence of adverse events or other undesirable side effects during clinical development; (iii) whether Nurix will have adequate resources to fund its obligations under the Nurix-Roche collaboration; (iv) whether the parties will be able to successfully co-commercialize bexobrutideg in the United States; and (v) other risks and uncertainties described under the heading “Risk Factors” in Nurix’s Quarterly Report on Form 10-Q for the fiscal period ended May 31, 2026, and other SEC filings. Accordingly, readers are cautioned not to place undue reliance on these forward-looking statements. The statements in this press release speak only as of the date of this press release, even if subsequently made available by Nurix on its website or otherwise. Nurix disclaims any intention or obligation to update publicly any forward-looking statements, whether in response to new information, future events, or otherwise, except as required by applicable law. 

Contacts: 
Media & Investors 
Kris Fortner 
Nurix Therapeutics, Inc. 
kfortner@nurixtx.com