Study of NX-5948 Versus Pirtobrutinib in R/R CLL/SLL

August 27, 2026 updated by: Nurix Therapeutics, Inc.

A Phase 3, Randomized, Open-label, Multicenter Study of NX-5948 Versus Pirtobrutinib in Relapsed/Refractory (R/R) Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL)

The study will evaluate the efficacy and safety of NX-5948 (bexobrutideg) versus pirtobrutinib in participants with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) who are relapsed or refractory to prior covalent Bruton tyrosine kinase inhibitor (cBTKi) treatment.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

620

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United States
    • Georgia
      • Macon, Georgia, United States, 31210
        • Recruiting
        • Central Georgia Cancer Care
    • Indiana
      • Fort Wayne, Indiana, United States, 46804
        • Recruiting
        • Fort Wayne Medical Oncology and Hematology
      • Indianapolis, Indiana, United States, 46260
        • Recruiting
        • Hematology Oncology of Indiana
    • Tennessee
      • Nashville, Tennessee, United States, 37203
        • Recruiting
        • SCRI Oncology Partners
    • Texas
      • Midland, Texas, United States, 79124
        • Recruiting
        • Texas Oncology - West Texas
    • Virginia
      • Fairfax, Virginia, United States, 22201
        • Recruiting
        • Virginia Cancer Specialists

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Key Inclusion Criteria:

  • Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
  • Adequate organ and bone marrow function
  • Confirmed diagnosis of CLL/SLL that meets iwCLL 2018 criteria for diagnosis and systemic treatment
  • Received at least 1 prior line of therapy for CLL/SLL that included a cBTKi and must have documented disease progression during treatment with, or after discontinuation of, the cBTKi
  • Participants with SLL must have measurable disease by computed tomography (CT) per iwCLL

Key Exclusion Criteria:

  • Known or suspected prolymphocytic leukemia or Richter's transformation at any time preceding enrollment
  • Investigational agent or anticancer therapy within 5 half-lives or 14 days (whichever is shorter) prior to planned start of study treatment
  • Ongoing systemic corticosteroids ≥10 mg/day prednisone or equivalent
  • Previously treated with a BTK degrader or a noncovalent BTKi
  • Myocardial infarction, unstable angina, unstable symptomatic ischemic heart disease, placement of a coronary arterial stent, or any other significant cardiac condition within 6 months of planned start of study treatment
  • Thromboembolic events, stroke, or intracranial hemorrhage within 6 months of planned start of study treatment

Note: Other Inclusion/Exclusion criteria may apply as defined in the protocol.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Arm A: NX-5948
Drug: NX-5948
Administered orally once daily
Other Names:
  • Bexobrutideg
Experimental: Arm B: Pirtobrutinib
Drug: Pirtobrutinib
Administered orally once daily per prescribing information
Other Names:
  • JAYPIRCA

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Progression-free survival (PFS) as assessed by Independent Review Committee (IRC)
Time Frame: Up to approximately 3.5 years
Time from randomization to disease progression per 2018 International Workshop on CLL (iwCLL) or death due to any cause, whichever is earlier
Up to approximately 3.5 years
Objective response rate (ORR) without partial response with lymphocytosis (PR-L) as assessed by IRC
Time Frame: Up to approximately 2.5 years
Percentage of participants with best overall response of complete response (CR)/CR with incomplete marrow recovery (CRi), partial response (PR), or nodular PR, as assessed per 2018 iwCLL guidelines
Up to approximately 2.5 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pharmacokinetic profile of NX-5948
Time Frame: Up to Cycle 13 Day 1 (each cycle is 28 days)
NX-5948 concentrations in blood samples
Up to Cycle 13 Day 1 (each cycle is 28 days)
Overall survival
Time Frame: Up to approximately 7 years
Time from randomization to death from any cause
Up to approximately 7 years
PFS as assessed by the investigator
Time Frame: Up to approximately 3.5 years
Time from randomization to disease progression or death due to any cause, whichever is earlier
Up to approximately 3.5 years
Objective response rate (ORR) with and without partial response with lymphocytosis (PR-L) as assessed by IRC and investigator
Time Frame: Up to approximately 3.5 years
Percentage of participants with best overall response of complete response (CR)/CR with incomplete marrow recovery (CRi), partial response (PR) or nodular PR, or PR-L (for ORR with PR-L), as assessed per 2018 International Workshop on CLL (iwCLL) guidelines
Up to approximately 3.5 years
Duration of response with and without PR-L as assessed by IRC and investigator
Time Frame: Up to approximately 3.5 years
Time from the date of the first response to documented disease progression or death due to any cause, whichever is earlier
Up to approximately 3.5 years
Time to next anti-CLL/SLL treatment as assessed by IRC and by investigator
Time Frame: Up to approximately 3.5 years
Time from randomization to the date of next anti-CLL/SLL treatment
Up to approximately 3.5 years
Change from baseline in global health status/quality of life on the European Organization for Research and Treatment of Cancer Quality of Life Cancer Questionnaire C30 with CLL module (EORTC QLQ-C30-CLL17)
Time Frame: Baseline and up to approximately 3.5 years
Percentage of participants with a clinically meaningful change from baseline using the EORTC QLQ-C30-CLL17 questionnaire to assess global health and overall quality of life
Baseline and up to approximately 3.5 years
Change from baseline in EuroQol-5 Dimensions, 5-level Questionnaire (EQ-5D-5L)
Time Frame: Baseline and up to approximately 3.5 years
Percentage of participants with a clinically meaningful change from baseline using the EQ-5D-5L questionnaire to assess health outcomes
Baseline and up to approximately 3.5 years
Number of participants with treatment-emergent adverse events
Time Frame: Up to approximately 3.5 years
Up to approximately 3.5 years
Number of participants with clinically significant changes from baseline in laboratory parameters
Time Frame: Up to approximately 3.5 years
Laboratory parameters may include hematology, clinical chemistry, and urinalysis
Up to approximately 3.5 years
Number of participants with clinically significant changes from baseline in vital signs
Time Frame: Up to approximately 3.5 years
Vital signs include blood pressure, heart and respiratory rates, pulse oximetry, and temperature
Up to approximately 3.5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Nurix Therapeutics, Inc.

Investigators

  • Study Director: Study Director, Nurix Therapeutics, Inc.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 3, 2026

Primary Completion (Estimated)

October 1, 2029

Study Completion (Estimated)

August 1, 2033

Study Registration Dates

First Submitted

March 31, 2026

First Submitted That Met QC Criteria

March 31, 2026

First Posted (Actual)

April 7, 2026

Study Record Updates

Last Update Posted (Actual)

August 31, 2026

Last Update Submitted That Met QC Criteria

August 27, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • NX-5948-306
  • 2025 (U.S. NIH Grant/Contract: Faculty of Social Sciences Scientific Grant at the University of Gdańsk)
  • 2025-524145-27-00 (Ctis)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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