An interventional study of Diet in CLL (Chronic Lymphocytic Leukemia), sponsored by Technical University of Munich. Recruiting at 1 site in Germany. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-23.
Sponsored by Technical University of Munich · Not applicable, Interventional, and Other
The goal of this clinical trial is to investigate whether a short-term (4-week) whole-food, plant-based (WFPB) diet has an effect on metabolism, immune function, and disease activity in early-stage chronic lymphocytic leukemia (CLL). The main questions the study aims to answer are:
Researchers will examine whether a WFPB diet can affect absolute lymphocyte counts in participants' blood and what metabolic or functional changes occur within the CLL cells.
Participants will:
This is a prospective, exploratory, single-arm pilot study designed as a pre-post comparison in which each participant serves as their own control. The aim of the trial is to investigate whether a short-term (4-week) whole-food, plant-based (WFPB) diet influences disease activity, immune function, and metabolism in patients with early-stage, treatment-naïve chronic lymphocytic leukemia (CLL) who are currently managed with a watch-and-wait strategy. Up to 50 participants will be enrolled.
The primary objective is to assess whether a WFPB diet impacts disease activity, as reflected by changes in absolute lymphocyte counts and other hematologic parameters. Secondary objectives include examining the effects of the dietary intervention on immune cell subsets, their signaling pathways, and cell-cell interactions. In addition, the study will evaluate changes in microbiome composition and related metabolic processes, as well as explore systemic metabolic shifts through targeted and untargeted omics analyses. These include metabolomics, lipidomics, and other exploratory omics approaches, conducted on a subset of participants.
Additional health-related outcomes will also be assessed. These include anthropometric and metabolic markers such as body weight, body mass index (BMI), body composition (lean mass and fat mass), blood glucose, lipid profiles, and systemic inflammatory markers. Stool samples will be analyzed for microbiome composition and metabolites, while blood samples will be used for flow cytometry-based immune profiling, signaling analyses, and exploratory omics assays.
The dietary intervention is defined as a whole-food, plant-based diet that excludes highly processed foods, minimizes intake of moderately processed foods, eliminates all animal-derived foods, and reduces consumption of sugar-sweetened and alcoholic products. Participants will be encouraged to eat to satiety without restriction on quantity. A certified dietary instructor will provide individualized counseling, taking into account each participant's baseline dietary habits and lifestyle. Adherence will be monitored through a food diary kept during the week prior to study initiation and throughout the 4-week intervention.
Study visits will take place at baseline (prior to dietary change), after 14 days, and after 28 days. At each visit, blood and stool samples will be collected, clinical assessments will be performed, and at day 0 and 28 body composition will be measured. The trial is exploratory in nature, aiming to generate hypotheses and mechanistic insights into the potential of a short-term dietary intervention to modulate disease biology and systemic metabolism in CLL.
190 studies on the registry are indexed under Leukemia, B-Cell; 52 are open to participants now.
This study's planned enrollment of 50 is above the median of 39 across 162 interventional studies indexed under Leukemia, B-Cell.
Browse Leukemia, B-Cell studies →Technical University of Munich is the lead sponsor of 320 studies on the registry; 58 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All participants will receive nutrition counselling and partake in the WFPB diet for 4 weeks. Participants will be asked to keep a food diary.
Other: Diet
For 4 weeks the participants will sick to a whole-food plant-based diet and keep a food diary. Recommendations and guidelines will be given during a nutritional counselling.
Effect on absolute lymphocyte count
Leukocyte and Lymphocyte count will be measured from whole blood via the in-houseclinical chemistry pipeline.
Time frame: Before the intervention at day 0, during the intervention at day 14 and after the intervention at day 28
Effect on Microbiomecomposition
Firmicutes to Bacteriodota ratio (%) will be analysed via 16S rRNA sequencing
Time frame: Before the intervention at day 0, during the intervention at day 14 and after the intervention at day 28
Effect immune cell composition
Composition of immune cell populations will be investigated via Spectral Flow Cytometry-based phenotyping and given in %
Time frame: Before the intervention at day 0, during the intervention at day 14 and after the intervention at day 28
Changes in Metabolism
Changes in concentration of metabolites via Metabolomics/Lipidomics from serum and PBMCs.
Time frame: Before the intervention at day 0 and after the intervention at day 28
Changes in Serum lipids
Lipid concentrations will be evaluated by the clinics in house pipeline.
Time frame: Before the intervention at day 0, during the intervention at day 14 and after the intervention at day 28.
Effect on body weight
Body weight is measured in kg
Time frame: Before the intervention at day 0 and after the intervention at day 28
Plan to share: Yes — We will support the international committee of medical journal editors (ICMJE) and the ethical obligation of responsible sharing of data from clinical trials. De-identified individual participant data collected during the trial will be shared, including clinical and laboratory data. Supporting documents such as the study protocol, statistical analysis plan, and informed consent form will also be provided.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Data sharing will begin 9 months after the primary results are published and will be available for up to 3 years. Extensions may be considered upon request.
Access criteria: Data access will be granted to qualified researchers from academic or non-profit institutions following review and approval of a research proposal and execution of a data sharing agreement. Requests should be submitted via email to Maike Buchner-Mayr.
No publications or documents are linked to this record.
Started Jan 2024 (actual). Primary completion is estimated for Jun 2028, 53 months after the start.
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