Determinants of the Response to BTK Degraders (BTKd) in Chronic Lymphocytic Leukemia

Chronic Lymphocytic Leukemia (CLL) is a malignant hematological disease of B cells, primarily observed in older adults. Although it is classified among indolent hematological malignancies, CLL exhibits significant heterogeneity, both in terms of its biological characteristics and its disease progression and the therapeutic strategies employed. In patients requiring treatment, the disease can relapse. Until recently, immunochemotherapy remained the standard treatment for this disease, but the last decade has seen the emergence of oral targeted therapies, such as Bruton's tyrosine kinase inhibitors (BKT1s) and BCL-2 inhibitors (BCL-2 inhibitors), which have profoundly altered patient prognosis. While the introduction of these two classes of drugs has led to improved prognosis, a rare but significant subgroup of patients, known as "double refractory," has emerged. These patients, exposed to both BKT and BCL-2 inhibitors and who have become refractory to both treatments, have a poor prognosis. To overcome this problem of resistance, molecules targeting the degradation of the BTK protein (BTKd) are currently under development. The main investigator propose the creation of a cohort and a biobank of samples from CLL patients who are candidates for or have been exposed to BTKd, in order to study the mechanisms of response and resistance to these molecules.

Inclusion criteria

• Patient with CLL candidates ou exposed to BTKd
• Patient who has provided informed consent to participate in the study.
• Patient covered by a social security health insurance plan

Exclusion criteria

• Minor patients.
• Adults under guardianship.
• Protected persons.