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
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.
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.
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 →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.
Adequate hematopoietic function within 7 days before the participant's enrollment
Exclusion Criteria:
Clinically significant cardiovascular disease including the following:
However, participants with the following history /conditions that have been treated with a curative intent are allowed:
Woman with adjuvant endocrine therapy (I.e., hormonotherapy) after breast cancer treatment can be enrolled if hormonotherapy was started for ≥ 2 years
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
Zanubrutinib is a Bruton tyrosine kinase (BTK) inhibitor administered orally.
Also known as: BRUKINSA
Progression-Free Survival (PFS)
The primary endpoint is the Progression-Free Survival (PFS).
Time frame: 30 months and 5 years
Permanent Treatment Discontinuation (PTD) Rate
The key secondary endpoint is the rate of permanent treatment discontinuation (PTD).
Time frame: 18 months
Overall Survival (OS)
The secondary efficacy endpoint 1 is the Overall Survival (OS).
Time frame: At 30 months and at 5 years
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
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
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
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.
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.
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.
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).
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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Leukemia, Lymphocytic, Chronic, B-Cell→
The Lymphoma Academic Research Organisation