Nurix Therapeutics Presents New Data from the Phase 1 Trial of Bexobrutideg (NX-5948) in Waldenström Macroglobulinemia at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition

Rhea-AI Summary

Nurix Therapeutics (Nasdaq: NRIX) presented Phase 1 data for BTK degrader bexobrutideg (NX-5948) in relapsed/refractory Waldenström macroglobulinemia at ASH on December 8, 2025.

In 31 treated patients (median age 71), 28 were evaluable and achieved an objective response rate (ORR) of 75.0% (VGPR 10.7%, PR 50.0%, MR 14.3%). Median follow-up was 8.1 months; median duration of response and median progression-free survival were not reached. Responses occurred regardless of MYD88/CXCR4 status, and 14 patients remained on treatment >6 months.

Safety was manageable: common AEs included neutropenia 29.0% and diarrhea 25.8%; no dose-limiting toxicities or grade 5 AEs were observed.

Positive

• ORR 75.0% in 28 evaluable patients
• VGPR 10.7% (3 patients)
• Median follow-up 8.1 months; DOR and PFS not reached
• Responses observed regardless of MYD88/CXCR4 mutation status
• 14 patients remained on treatment >6 months

Negative

• Neutropenia reported in 29.0% of patients
• Petechiae reported in 29.0% of patients
• Diarrhea reported in 25.8% of patients
• Two treatment-emergent adverse events led to discontinuation
• Small cohort size: 31 treated patients limits broader generalizability

Key Figures

Objective response rate 75.0% Phase 1 WM cohort (28 evaluable patients)

Subgroup ORR 82.6% Patients with ≥2 disease assessments (n=23)

Disease control rate 100.0% Subgroup with ≥2 disease assessments (n=23)

WM patients 31 patients (n=31) Waldenström macroglobulinemia Phase 1a/1b trial population

Median follow-up 8.1 months Data cut as of September 19, 2025

Median age 71.0 years WM patients (range 49–88 years)

Median prior lines 3 prior therapies WM patients (range 1–7)

CNS involvement 3 patients (9.7%) WM patients with CNS disease at baseline

Market Reality Check

$19.07 Last Close

Volume Volume 1,228,459 is below 20-day average 1,560,618 (relative volume 0.79x). normal

Technical Shares at $18.09 are trading above the 200-day MA of $11.54 and about 21.18% below the 52-week high.

Peers on Argus 1 Up

NRIX was up modestly while only one scanned peer, PRME, showed upside momentum (+6.15%) and others in the broader peer list were mixed, indicating today’s setup looks more stock-specific than sector-driven.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Dec 01	Clinical webcast plan	Positive	-4.4%	Announced webcast to review new Phase 1 bexobrutideg data at ASH.
Nov 25	Conference participation	Neutral	-0.9%	Noted participation and webcast for Piper Sandler healthcare conference.
Nov 10	Board appointment	Positive	-0.5%	Added experienced oncology leader Roger Dansey to board of directors.
Nov 07	Clinical data update	Positive	-1.7%	Presented Phase 1 NX-1607 data showing immune activation and remodeling.
Nov 03	ASH presentations plan	Positive	-2.5%	Announced upcoming ASH presentations, including updated NX-5948 data.

Pattern Detected

Recent history shows a pattern of negative price reactions following generally positive or strategic news, especially around clinical and data-presentation updates.

Recent Company History

Over the last six months, Nurix has repeatedly highlighted clinical and strategic progress. Updates on BTK degrader bexobrutideg and other programs, ASH presentation announcements on Dec 8, and a new board appointment on Nov 10, 2025 were followed by mostly negative single‑day moves. Earlier, positive bexobrutideg data for CLL and WM on Jun 12, 2025 also saw a share-price decline. Today’s detailed WM Phase 1 data further extend this clinical narrative around bexobrutideg and BTK degradation.

Market Pulse Summary

The stock surged +18.7% in the session following this news. A strong positive reaction aligns with the encouraging WM Phase 1 data, including an ORR of 75.0% and subgroup ORR of 82.6% with a 100.0% disease control rate. Historically, NRIX often traded down on positive clinical headlines, so a large upside move would contrast with prior divergence. Investors could watch how durability metrics evolve beyond the current 8.1‑month median follow‑up and whether subsequent updates maintain the current efficacy and tolerability profile.

Key Terms

waldenström macroglobulinemia medical

"Objective response rate (ORR) of 75.0% including three very good partial responses (VGPR) in heavily pre-treated Waldenström macroglobulinemia patients"

A rare type of blood cancer in which a specific white blood cell makes too much of a single antibody protein, causing blood to become thick and organs to be affected; symptoms can include fatigue, bleeding, nerve problems and vision changes. Investors care because new tests, drugs or approvals for this condition can create meaningful markets or revenue shifts for healthcare companies, similar to how a new product launch can change a company’s prospects.

objective response rate medical

"Objective response rate (ORR) of 75.0% including three very good partial responses"

The objective response rate (ORR) is the percentage of patients in a clinical trial whose tumors measurably shrink or disappear according to preset rules. Investors use it as a quick, objective signal of a drug’s ability to produce a clear treatment effect—like counting how many plants visibly respond after applying a new fertilizer—and higher ORR can improve odds of regulatory approval, commercial success, and company valuation.

progression-free survival medical

"median duration of response (DOR) and median progression-free survival (PFS) have not been reached"

Progression-free survival is the length of time during and after a treatment that a patient's disease does not get worse, measured from the start of treatment until the disease shows measurable signs of progression or the patient dies. Investors care because longer progression-free survival in clinical trials often signals that a drug is effective, improving chances of regulatory approval, market adoption, and revenue potential—think of it as a stopwatch showing how long a therapy can keep the illness at bay.

bruton’s tyrosine kinase medical

"its Bruton’s tyrosine kinase (BTK) degrader bexobrutideg (NX-5948)"

A cellular enzyme that acts like a light switch controlling growth and activity of certain immune cells called B cells; when it’s overactive it can drive blood cancers and immune disorders. Investors care because drugs that block this enzyme can become prescription treatments or face clinical trial and regulatory risk, making pipeline progress, approval decisions, and safety results key value drivers for healthcare companies.

btk degrader medical

"Phase 1 clinical trial of its Bruton’s tyrosine kinase (BTK) degrader bexobrutideg"

A BTK degrader is a type of drug designed to attach to Bruton’s tyrosine kinase (BTK) — a protein that helps certain immune and cancer cells survive — and mark it for removal by the cell’s disposal system. For investors, BTK degraders matter because they can potentially work when older BTK-blocking drugs fail, may reduce long-term side effects, and could expand or shift market opportunities in cancer and autoimmune treatments.

bcl2 inhibitor medical

"four patients had received prior treatment with a BCL2 inhibitor (12.9%)"

A BCL2 inhibitor is a type of drug that blocks the BCL2 protein, which normally helps cells avoid programmed death; by disabling that safety switch, the drug encourages diseased cells (often cancer cells) to die. Investors pay attention because these drugs can change treatment outcomes, affect regulatory approval prospects, and drive sales or partnerships—think of them as targeted tools that can open new markets or boost the value of a drug portfolio if they prove safe and effective.

central nervous system medical

"Three patients (9.7%) had central nervous system (CNS) involvement at baseline"

The central nervous system (CNS) is the body's main control center, made up of the brain and spinal cord, that processes information and directs movement, sensation and basic functions like breathing. For investors, CNS-related products and research matter because they face long development times, strict safety testing and regulatory hurdles; success or failure can dramatically affect a company’s costs, timelines and potential market value.

very good partial responses medical

"including very good partial responses (VGPR) in three patients (10.7%)"

A very good partial response describes a significant but not complete improvement in a patient’s condition after treatment, where measurable signs of disease shrink or symptoms lessen substantially though some disease remains. For investors, this signals that a drug or therapy is working well enough to change clinical outcomes and could speed development or regulatory decisions, similar to a product that doesn’t solve every problem but clearly outperforms competitors in early tests.

AI-generated analysis. Not financial advice.

Objective response rate (ORR) of 75.0% including three very good partial responses (VGPR) in heavily pre-treated Waldenström macroglobulinemia patients

With a median follow up of 8.1 months, median duration of response (DOR) and median progression-free survival (PFS) have not been reached

Encouraging efficacy and favorable tolerability support continued development of bexobrutideg in Waldenström macroglobulinemia

Nurix will host a webcast to discuss the data presented at the ASH Annual Meeting and provide a corporate update today at 8:15 p.m. ET

BRISBANE, Calif., Dec. 08, 2025 (GLOBE NEWSWIRE) -- Nurix Therapeutics, Inc. (Nasdaq: NRIX), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of targeted protein degradation medicines in oncology and autoimmune disease, today presented new clinical data from patients with relapsed or refractory Waldenström macroglobulinemia (WM) treated in the Phase 1 clinical trial of its Bruton’s tyrosine kinase (BTK) degrader bexobrutideg (NX-5948). These data will be presented by Scott Huntington M.D., MPH, Associate Professor of Internal Medicine (Hematology), Yale School of Medicine, and a clinical investigator on the trial, on December 8, 2025, at 6 p.m. ET at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition being held in Orlando, FL.

“The data presented at ASH in this older and heavily pre-treated WM population that includes patients with MYD88 and CXCR4 mutations continue to demonstrate encouraging activity of bexobrutideg with durable and deepening responses with longer time on treatment,” said Paula G. O’Connor, M.D., chief medical officer of Nurix. “Bexobrutideg was well tolerated, consistent with the overall study population and previous disclosures.”

“Collectively, these clinical data and recent data highlighting the unique properties of our potent and highly selective BTK degrader contribute to a growing body of evidence that support bexobrutideg’s potential to be the best-in-class and an important new therapeutic option for patients,” said Arthur T. Sands, M.D., Ph.D., president and chief executive officer of Nurix. “We believe bexobrutideg is an innovative therapy with the potential to transform care in CLL, WM, and additional NHL indications, while supporting long-term value creation as its development expands into inflammatory and autoimmune settings.”

The data presented at the 2025 ASH Annual Meeting include patients with WM (n=31) treated with bexobrutideg at doses ranging from 200 mg to 600 mg once daily by oral administration from both the Phase 1a dose escalation and Phase 1b cohort expansions. Among the 31 WM patients, the median age was 71.0 years (range 49–88 years), and the median number of prior lines of therapy was 3 (range 1-7). All 31 patients previously had been treated with a BTK inhibitor (100%), 28 had received prior chemotherapy/chemo-immunotherapy (90.3%), four had received prior non-covalent BTK inhibitor (12.9%), and four patients had received prior treatment with a BCL2 inhibitor (12.9%). Twenty-four patients (77.4%) had mutations in MYD88, and six patients (19.4%) had mutations in CXCR4. Three patients (9.7%) had central nervous system (CNS) involvement at baseline.

Bexobrutideg was well tolerated in patients with WM, consistent with the overall study population and previous disclosures. Adverse events (AEs) were predominantly low grade with the most common being neutropenia (29.0%), petechiae (29.0%), diarrhea (25.8%), anemia (22.6%), purpura/contusion (22.6%), and thrombocytopenia (19.4%). There were no dose limiting toxicities observed and no grade 5 AEs. Two treatment emergent AEs led to drug discontinuation. No new onset atrial fibrillation was observed.​

As of the September 19, 2025 data cut, 28 patients were evaluable for response. Bexobrutideg demonstrated an objective response rate (ORR) of 75.0%, including very good partial responses (VGPR) in three patients (10.7%), partial responses (PR) in 14 patients (50.0%), and minor responses (MR) in four patients (14.3%). Six patients (21.4%) had a best response of stable disease (SD). In a subgroup analysis of patients with 2 or more disease assessments (n=23), ORR was 82.6% and disease control rate (DCR) was 100.0%.

Responses were observed in patients regardless of their baseline mutations in MYD88 and CXCR4. Out of three patients with CNS involvement (2 with systemic disease), two have responded and none progressed. Overall, responses were durable. With a median follow up of 8.1 months, median duration of response and median progression-free survival were not reached. As of the September 19, 2025 data cut, fourteen patients had continued on treatment for more than six months, and six patients had remained on treatment for more than one year.

Nurix Webcast Details
Date and time: Monday, December 8, 2025, 8:15 p.m. ET
Access Details: The live webcast and subsequent archived replay will be available in the Events section of the Investor page of the Nurix website at ir.nurixtx.com.

About Bexobrutideg (NX-5948)
Bexobrutideg is an investigational, orally bioavailable, brain penetrant, highly selective small molecule degrader of BTK currently being evaluated in the DAYBreak CLL-201 clinical trial (NCT07221500), a pivotal single-arm Phase 2 study of bexobrutideg in patients with relapsed or refractory chronic lymphocytic leukemia. Nurix also continues enrollment in the NX-5948-301 Phase 1a/1b clinical trial (NCT05131022) of bexobrutideg in patients with relapsed or refractory B cell malignancies.

About Nurix Therapeutics, Inc.
Nurix Therapeutics is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of targeted protein degradation medicines, the next frontier in innovative drug design aimed at improving treatment options for patients with cancer and inflammatory diseases. Nurix’s wholly owned, clinical stage pipeline includes degraders of Bruton’s tyrosine kinase (BTK), a B-cell signaling protein, and inhibitors 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 also is advancing multiple potentially first-in-class or best-in-class degraders and degrader antibody conjugates (DACs) in its preclinical pipeline. Nurix’s partnered drug discovery pipeline consists of preclinical stage degraders of IRAK4 and STAT6, as well as multiple additional programs 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 for multiple drug candidates. Powered by a fully AI-integrated discovery engine capable of tackling 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, writing medicine’s next chapter with a new script to outmatch disease. Nurix is headquartered in San Francisco, California. For additional information visit http://www.nurixtx.com.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995 and other federal securities laws. 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: the tolerability, safety profile, therapeutic potential and other advantages of bexobrutideg; and the potential role of bexobrutideg in the treatment of patients with chronic lymphocytic leukemia (CLL), Waldenström macroglobulinemia, and non-Hodgkin lymphoma (NHL) indications. 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) the risks inherent in the drug development process, including the unexpected emergence of adverse events or other undesirable side effects during clinical development; (ii) uncertainties related to the timing and results of clinical trials; (iii) whether Nurix will be able to fund its research and development activities and achieve its research and development goals; (iv) the impact of economic and market conditions and global and regional events on Nurix’s business, clinical trials, financial condition, liquidity and results of operations; (v) whether Nurix will be able to protect intellectual property and (vi) other risks and uncertainties described under the heading “Risk Factors” in Nurix’s Quarterly Report on Form 10-Q for the fiscal period ended August 31, 2025, 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:
Investors
Kris Fortner
Nurix Therapeutics, Inc.
Kfortner@nurixtx.com

Elizabeth Wolffe, Ph.D.
Wheelhouse Life Science Advisors
lwolffe@wheelhouselsa.com

Media
Aljanae Reynolds
Wheelhouse Life Science Advisors
areynolds@wheelhouselsa.com

FAQ

What were the key efficacy results for Nurix's NRIX bexobrutideg at ASH Dec 8, 2025?

In 28 evaluable WM patients, bexobrutideg delivered an ORR of 75.0% with VGPR in 10.7%; median DOR and PFS were not reached at 8.1 months median follow-up.

How many Waldenström patients were treated with NRIX bexobrutideg and what was their profile?

Thirty-one patients were treated (median age 71), median prior lines of therapy 3, and 100% had prior BTK inhibitor exposure.

What safety signals were reported for bexobrutideg in the NRIX Phase 1 WM cohort?

Adverse events were mainly low grade; common AEs included neutropenia 29.0%, petechiae 29.0%, and diarrhea 25.8%; no dose-limiting toxicities or grade 5 AEs observed.

Did NRIX report responses in patients with MYD88 or CXCR4 mutations in the ASH dataset?

Yes; responses were observed regardless of baseline MYD88 or CXCR4 mutation status.

How durable were responses to bexobrutideg in the NRIX Phase 1 WM patients?

With median follow-up of 8.1 months, median duration of response and median PFS were not reached; 14 patients remained on treatment >6 months.

Where can investors watch Nurix's webcast on the ASH data for NRIX bexobrutideg?

The live webcast and archived replay are available in the Events section of Nurix investor website at ir.nurixtx.com.