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Not yet recruitingNCT07739459ZEN-CLLUpdated Sep 14, 2026

Study of Zanubrutinib in Older Patients With Previously Untreated Chronic Lymphocytic Leukemia (CLL)

A Phase 2 interventional study of Zanubrutinib in Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma, sponsored by The Lymphoma Academic Research Organisation. Not yet recruiting at 17 sites in France. Open to participants aged 80 Years and older. Per ClinicalTrials.gov, last updated 2026-09-14.

Sponsored by The Lymphoma Academic Research Organisation · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
95
Allocation
Not applicable
Ages
80 Years and older
Sex
All
01

Study summary

This phase II, open-label, multicenter study evaluates zanubrutinib in patients aged 80 years and older with previously untreated chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) who require treatment.

CLL and SLL are slow-growing blood cancers that mainly affect older adults. Although zanubrutinib is an effective treatment, taking it continuously at the full dose may increase the risk of side effects over time, particularly in elderly patients. The study aims to assess whether a planned reduction in the dose of zanubrutinib after an initial period of treatment can maintain disease control while improving long-term tolerability.

Read the detailed description

The ZEN-CLL study is evaluating a treatment strategy based on zanubrutinib in previously untreated elderly patients with CLL or small lymphocytic lymphoma (SLL). Approximately 95 participants will be enrolled in 17 LYSA centers in France.

All participants will receive zanubrutinib 160 mg twice daily for the first 18 months of treatment. After Month 18, the dose will be reduced according to the dose received at that time and the participant's tolerability. Treatment will continue until permanent treatment discontinuation or the end of study participation.

The study aims to determine whether this dose reduction strategy can maintain disease control while improving long-term tolerability in this elderly population.

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Conditions studied

  • Chronic Lymphocytic Leukemia
  • Small Lymphocytic Lymphoma

Keywords

  • Chronic lymphocytic leukemia
  • Small lymphocytic lymphoma
  • Zanubrutinib
  • BTK inhibitor
  • First-line treatment
  • Treatment-naïve patients
03

In context

Leukemia, Lymphocytic, Chronic, B-Cell

1,603 studies on the registry are indexed under Leukemia, Lymphocytic, Chronic, B-Cell; 243 are open to participants now.

This study's planned enrollment of 95 is above the median of 40 across 1,325 interventional studies indexed under Leukemia, Lymphocytic, Chronic, B-Cell.

Browse Leukemia, Lymphocytic, Chronic, B-Cell studies →

Lead sponsor

The Lymphoma Academic Research Organisation is the lead sponsor of 60 studies on the registry; 12 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
80 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Participant who understands and voluntarily signs and dates an informed consent form prior to any studyspecific assessments/procedures being conducted, including consent for specific biology analysis
  • Must be able to adhere to the trial visit schedule and other protocol requirements
  • ≥ 80 years at the time of signing the informed consent form (ICF) with no upper age limit
  • Previously untreated and documented CLL or small lymphocytic lymphoma (SLL), with a Royal Marsden Hospital (RMH) or Matutes Score of 4 or 5. For SLL a detectable clone with a CLL phenotype in the peripheral blood is a prerequisite for trial participation.
  • Participant requiring treatment according to 2018 IWCLL guidelines
  • ECOG performance status 0 to 2
  • Life expectancy > 6 months
  • Adequate hematopoietic function within 7 days before the participant's enrollment

    • ANC ≥ 0.75 G/L
    • And Platelets ≥ 50 G/L Note: Platelets transfusions may be administered during screening to meet this requirement
  • Hemoglobin level > 9g/dL, regardless of transfusion
  • Adequate renal function defined by a Creatinine Clearance ≥ 30 ml/min calculated according to MDRD or CKD-EPI or Cockcroft-Gault (using actual body weight).
  • Adequate liver function, as indicated by a total bilirubin \<1.5 x ULN, AST and ALT \<3 x ULN value, unless directly attributed to the participant's CLL/SLL or to Gilbert's Syndrome (the ULN is based on institutionalvalues)
  • Participant covered by any social security system
  • Participant who understands and speaks the country official language unless local regulation authorizes independent translator

Exclusion criteria

Exclusion Criteria:

  • Any prior CLL or SLL-specific therapies, even including rituximab used for autoimmune cytopenias.
  • Clinically significant cardiovascular disease including the following:

    1. Myocardial infarction within 6 months prior to ICF signature
    2. Unstable angina within 3 months prior to ICF signature
    3. NYHA class III or IV heart failure
    4. Uncontrolled hypertension
    5. History of clinically significant arrhythmias (including sustained ventricular tachycardia, ventricular fibrillation, or torsades de pointes).
    6. History of Mobitz II second- or third-degree heart block without permanent pacemaker
    7. Known LVEF \<50% as determined by echocardiography or multiple uptake gated acquisition (MUGA) scan
  • Child-Pugh liver cirrhosis
  • Clinical evidence for Central Nervous System involvement by CLL
  • Severe chronic obstructive lung disease with hypoxemia
  • Severe diabetes mellitus
  • Disease significantly affecting gastrointestinal function (malabsorption syndrome, stomach or small bowel resection)
  • Active or non-active autoimmune hemolytic anemia (AIHA) (isolated positive DAT is not an exclusion criterion, but reticulocytes/haptoglobin levels must be in lab normal ranges) or idiopathic thrombocytopenic purpura (ITP), requiring steroid therapy with > 20 mg daily of prednisone dose or equivalent.
  • Any prior history of Richter transformation or DLBCL
  • Any evidence or suspicion of Richter transformation or DLBCL during screening
  • Active malignancy other than the one treated in this trial. Prior history of malignancies unless the participant has been free of the disease for ≥ 2 years.

However, participants with the following history /conditions that have been treated with a curative intent are allowed:

  1. Non-invasive basal cell or epidermoid carcinoma (non melanoma)
  2. In situ carcinoma of the cervix
  3. In situ carcinoma of the breast
  4. Incidental histologic finding of prostate cancer (T1a or T1b) using the tumor, nodes, metastasis [TNM] clinical staging system
  5. Woman with adjuvant endocrine therapy (I.e., hormonotherapy) after breast cancer treatment can be enrolled if hormonotherapy was started for ≥ 2 years

    • History of stroke or intracranial hemorrhage within 6 months prior to ICF signature.
    • Major surgery 28 days before the ICF signature
    • History or known bleeding disorders (e.g hemophilia or von Willebrand disease)
    • Active Hepatitis C Virus (HCV) infection (RNA PCR-positive). Participants who received treatment for HCV infection that was intended to eradicate the virus may participate if hepatitis C RNA levels are undetectable
    • Active Hepatitis B Virus (HBV) infection (DNA PCR-positive). Participants with evidence of prior HBV infection but who are PCR-negative are permitted in the trial but should receive prophylactic antiviral therapy during the entire treatment with active monitoring of viral load in the blood
    • Patient with a positive HIV test before enrollment are eligible provided that they are stable on antiretroviral therapy for at least 4 weeks, have a CD4 count ≥ 200/uL, have an undetectable viral load, and have not had a history of opportunistic infection attributable to AIDS within the last 12 months.Known or suspected hypersensitivity or anaphylaxis to trial intervention including active substance or to any of the excipients.
    • Requires or receiving anticoagulation with warfarin or dual antiplatelets therapy equivalent vitamin K antagonists (other anticoagulants allowed: novel oral anticoagulant alone, aspirin alone, heparin alone).
    • Requires treatment with a strong/moderate cytochrome CYP3A4 inhibitor/inducer.
    • Participation in another clinical study who would compromise the participation to the current study.
    • Vaccinated with live, attenuated vaccines within 6 months of ICF
    • Use of any standard or experimental anti-cancer drug therapy within 28 days before the start (Day 1) of study treatment
    • Corticosteroid use > 20 mg per day within 1 week before the first dose of trial intervention, except as indicated for other medical conditions, such as inhaled steroid for asthma, topical steroid use, or as premedication for administration of trial intervention or contrast.
    • Any significant medical conditions, or laboratory abnormality or psychiatric illness likely to interfere with participation in this clinical trial or affect interpretation of trial outcomes (according to the investigator's decision)
    • Any uncontrolled and/or active significant infection (eg, bacterial, viral, or fungal; including participants with positive cytomegalovirus PCR).
    • Participant deprived of their liberty by a judicial or administrative decision
    • Participant hospitalized without consent
    • Adult participant under legal protection
05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
95 participants (estimated)

Study arms

  • Experimental
    Zanubrutinib

    Participants will receive oral zanubrutinib followed by a predefined dose reduction strategy. Treatment will continue until disease progression, permanent treatment discontinuation, withdrawal of consent, loss to follow-up, or the end of study participation.

    Drug: Zanubrutinib

Interventions

  • DrugZanubrutinib

    Zanubrutinib is a Bruton tyrosine kinase (BTK) inhibitor administered orally.

    Also known as: BRUKINSA

06

What researchers measure

Primary outcomes

  1. Progression-Free Survival (PFS)

    The primary endpoint is the Progression-Free Survival (PFS).

    Time frame: 30 months and 5 years

Secondary outcomes

  1. Permanent Treatment Discontinuation (PTD) Rate

    The key secondary endpoint is the rate of permanent treatment discontinuation (PTD).

    Time frame: 18 months

  2. Overall Survival (OS)

    The secondary efficacy endpoint 1 is the Overall Survival (OS).

    Time frame: At 30 months and at 5 years

  3. Time to Next Anti-Leukemia Treatment

    The secondary efficacy endpoint 2 is the Time to Next Anti-Leukemia Treatment (TTNLT).

    Time frame: At 30 months and at 5 years

  4. Overall Response Rate

    The secondary efficacy endpoints 3 and 4 are Overall Response Rate (ORR) at 18 months and at 30 months, respectively.

    Time frame: At 18 months and at 30 months

  5. Change From Baseline in Geriatric Assessment Scores

    Geriatric condition will be evaluated using minimal nurse-delivered scales recommended by the SIOG.

    Time frame: at baseline, at 18 months, at 30 months and at 42 months

  6. Health-Related Quality of Life

    Health-Related Quality of Life as assessed by Questionnaire

    Time frame: At baseline, every 3 months for the first 2 years, and every 6 months thereafter for 3 years.

  7. Frailty Assessment Score

    Frailty status will be assessed using a validated frailty scale.

    Time frame: At baseline, every 3 months for the first 2 years, and every 6 months thereafter for 3 years.

  8. Patient-Reported Treatment Side Effect Burden

    Treatment side effect burden will be assessed using a patient-reported questionnaire.

    Time frame: Baseline, every 3 months for the first 2 years, and every 6 months thereafter for 3 years.

  9. Incidence and Severity of Adverse Events (AEs), Serious Adverse Events (SAEs), and Adverse Events of Special Interest (AESIs)

    Safety will be assessed by the incidence, severity, and seriousness of adverse events, including serious adverse events and adverse events of special interest.

    Time frame: From first dose of study treatment until the end of study participation (up to 5 years).

07

Study locations

17 sites
  • Chu Lyon-Sud
    Lyon, Pierre Bénite 69310, France
  • Ch Victor Dupouy
    Argenteuil, 95107, France
  • Ch D'Avignon - Hopital Henri Duffaut
    Avignon, 84000, France
  • Ch de La Cote Basque
    Bayonne, 64109, France
  • Institut Bergonie
    Bordeaux, 33076, France
  • Ch Rene Dubos
    Cergy-Pontoise, 95303, France
  • Ch Sud Francilien
    Corbeil-Essonnes, 91106, France
  • Chu de Clermont-Ferrand
    Estaing, - SITE ESTAING, France
  • Chu de Grenoble
    Grenoble, 38700, France
  • Ch de Versailles - Hopital Andre Mignot
    Le Chesnay, 78157, France
    • Fatiha MERABET, doctor · Contact · fmerabet@ght78sud.fr
    • Fatiha MERABET, doctor · Principal investigator
  • Ch Du Mans-Centre de Cancerologie de La Sarthe
    Le Mans, 72000, France
    • Kamel LARIBI, doctor · Contact · klaribi@ch-lemans.fr
    • Kamel LARIBI, doctor · Principal investigator
  • Hopital Saint Vincent-de-Paul
    Lille, 59020, France
  • Centre Leon Berard
    Lyon, 69373, France
  • Chu Orleans
    Orléans, 45067, France
  • Centre Henri Becquerel
    Rouen, 76038, France
  • Iuct Oncopole
    Toulouse, 31059, France
  • Chru Nancy - Hôpital Brabois
    Vandœuvre-lès-Nancy, 54511, France
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 14, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT07739459
Lead sponsor
The Lymphoma Academic Research Organisation
Collaborators
Lymphoma Study Association, BeOne Medicines
Responsible party
Sponsor
First posted
Jul 31, 2026
Start date
Dec 2026 (estimated)
Primary completion
Apr 2029 (estimated)
Completion
Dec 2032 (estimated)
Last update
Sep 14, 2026

Study contacts

Project management
Contact
zen-cll@lysarc.org
+33 4 72 66 93 33
Loïc YSEBAERT, Professor
principal investigator · IUCT ONCOPOLE
Emmanuelle FERRANT, Doctor
principal investigator · Hospices Civils de Lyon

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.

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