A Study of NX-5948 in Adults With CLL/SLL Previously Treated With a Bruton's Tyrosine Kinase Inhibitor and a B-cell Lymphoma-2 Inhibitor (DAYBreak CLL-201)

The film gives the main points. The full list below is copied from the registry; the study team makes the final decision.

• Age18 Years to no maximum
• SexAll
• Healthy volunteersNo

You may be able to join if

• Age: ≥ 18 years
• Confirmed relapsed/refractory CLL/SLL that meets iwCLL criteria for diagnosis and systemic treatment
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• Must have received a covalent BTK inhibitor (BTKi), a non-covalent BTKi, and a BCL-2 inhibitor either in separate lines of therapy or in combination; a line of therapy is considered 2 or more consecutive cycles of a systemic anti-CLL/SLL regimen
• Participants with SLL must have measurable disease by radiographic assessment
• Adequate organ and bone marrow function
• Must sign an informed consent form indicating that he or she understands the purpose of the procedures required for the study and is willing to participate

You cannot join if

• Known or suspected prolymphocytic leukemia or Richter's transformation before entering study
• Investigational agent or anticancer therapy within 5 half-lives or 14 days (whichever is shorter) before planned start of study drug
• Antibody therapy must stop at least 4 weeks before the first dose of study drug
• No other systemic anticancer therapy is allowed at the same time as this study; exception: continuation of hormonal therapy for breast and prostate cancer is allowed, if they are not on the list of prohibited concomitant medications in this study
• Palliative limited-field radiotherapy within 7 days of the first dose of study or broad field radiotherapy within 28 days of first dose of study drug
• Use of systemic corticosteroids >20 mg/day prednisone or equivalent within the 7 days before start of study drug except for those used as premedication for radio diagnostic contrast
• Use of systemic immunosuppressive drugs other than systemic corticosteroids within 60 days before the first dose of study drug
• Previously treated with a BTK degrader
• Previous chimeric antigen receptor (CAR) T-cell therapy or allogeneic or autologous hematopoietic cell transplant within the past 90 days prior to enrollment
• Thromboembolic events (eg, deep vein thrombosis, pulmonary embolism, or symptomatic cerebrovascular events), stroke, or intracranial hemorrhage within 6 months of planned start of study drug
• Note: Other Inclusion/Exclusion criteria may apply as defined in the protocol.

This is how the treatment is meant to work. Whether it helps, and how safe it is, is what this trial is testing.

Treatments listed in the registry

• NX-5948 (Drug): Oral dose administered once daily. NX-5948 will be given in continuous 28-day cycles.

Na · Single Group · masking: None

Main goals

• Objective response rate without partial response with lymphocytosis (PR-L) as determined by an Independent Review Committee (IRC) (Up to approximately 5 years)

Other goals

• Objective response rate with PR-L as determined by IRC
• Objective response rate with and without PR-L as determined by investigator
• Duration of response as determined by IRC and by investigator
• Progression-free survival as determined by IRC and by investigator
• Complete response rate as determined by IRC and by investigator
• Time to response as determined by IRC and by investigator
• Overall survival
• Number of participants with treatment-emergent adverse events (TEAEs), Grade 3 or higher TEAEs, serious adverse events, and TEAEs leading to study drug discontinuation
• Number of participants with clinically significant changes from baseline in laboratory parameters
• Number of participants with clinically significant changes from baseline in vital signs
• Pharmacokinetic profile of NX-5948
• Change from baseline in Global Health Status/Quality of Life on the European Organization for Research and Treatment of Cancer QoL Questionnaire-Core 30 (EORTC QLQ-C30)
• Change from baseline in EuroQol-5 Dimensions, 5-level Questionnaire (EQ-5D-5L)

Planned enrollment: 100 (estimated).

• Banner MD Anderson Cancer Center, Phoenix, Arizona
• City of Hope, Duarte, California
• Cedars-Sinai Medical Center, Los Angeles, California
• Scripps Health, San Diego, California
• Colorado Blood Institute, Denver, Colorado
• University of Miami, Coral Gables, Florida
• Florida Cancer Specialists, Sarasota, Florida
• Fort Wayne Oncology and Hematology, Fort Wayne, Indiana
• Hematology Oncology of Indiana, Indianapolis, Indiana
• University of Iowa, Iowa City, Iowa
• Maryland Oncology Hematology, Silver Spring, Maryland
• Karmanos Cancer Center, Detroit, Michigan
• Duke University, Durham, North Carolina
• Novant Health Cancer Institute, Winston-Salem, North Carolina
• University of Cincinnati, Cincinnati, Ohio
• The Cleveland Clinic Foundation, Cleveland, Ohio
• The Ohio State University, Columbus, Ohio
• Oncology Hematology Care, Fairfield, Ohio
• UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania
• SCRI Oncology Partners, Nashville, Tennessee
• Texas Oncology - Center South, Austin, Texas
• University of Utah, Salt Lake City, Utah
• Virginia Cancer Specialists, PC, Fairfax, Virginia
• Oncology & Hematology Associates of Southwest VA, Norfolk, Virginia
• Virginia Oncology Associates, Norfolk, Virginia
• Fred Hutchinson Cancer Center, Seattle, Washington
• The Medical College of Wisconsin, Milwaukee, Wisconsin

13 recruiting sites outside the US. Site status as of Oct 30, 2026. Check the live record before contacting a site.

• ClinicalTrials.gov NCT07221500

Registry record reviewed as fetched Oct 30, 2026, last updated by the sponsor Sep 16, 2026. Public record; not medical advice.