Nantes University Hospital in France Launches Cohort Study to Analyze Resistance Mechanisms of BTK Degraders, Including Bexobrutideg
Launch of the REBELLE Cohort Study
Nantes University Hospital in France has initiated the 'REBELLE' (Prospective Cohort) study, enrolling patients with Chronic Lymphocytic Leukemia (CLL). This observational clinical trial (NCT07099443) aims to elucidate the mechanisms of drug resistance against Bruton's Tyrosine Kinase Degraders (BTKd), a new generation of targeted therapies. The study will comprehensively analyze blood, bone marrow, and lymph node samples from 60 patients with double-refractory disease, who have failed both conventional inhibitors and Bcl-2 inhibitors. This research is expected to provide novel clinical breakthroughs for patients with advanced hematological malignancies, garnering significant interest from both academia and industry.
Disruptive Innovation in Targeted Protein Degradation Technology
BTK degraders operate through a fundamentally different mechanism compared to conventional, covalent BTK inhibitors such as Ibrutinib (Imbruvica) and Zanubrutinib (Brukinsa). While inhibitors simply block protein activity, degraders utilize Targeted Protein Degradation (TPD) to destroy the BTK protein itself. This characteristic offers the potential to completely overcome resistance caused by mutations such as C481S, which can occur with long-term administration of inhibitors. However, how tumors develop new bypass resistance pathways in a real clinical setting remains unclear, making this cohort study crucial for understanding these mechanisms.
Active Investment by Global Big Pharma
Currently, Nurix Therapeutics' Bexobrutideg (NX-5948) and BeOne Medicines' BGB-16673 are in fierce competition in Phase 2 and Phase 3 clinical trials. Notably, Nurix signed a global co-development license agreement with Roche for Bexobrutideg in June 2026, with a total value of $2.3 billion, demonstrating the market value of this platform. The real-world genomic data generated by the REBELLE cohort will provide important guidance for the late-stage clinical trial design and subsequent pipeline development strategies of these leading companies.
Value of Multi-Omics Analysis and Genomic Data
Following patient enrollment, this study will conduct a five-year close-follow-up to establish a precise genomic and transcriptomic database. Next Generation Sequencing (NGS) and single-cell RNA sequencing technologies will be applied to observe the dynamic changes in the tumor microenvironment. Furthermore, 3D organoid models based on patient samples will be created, and CRISPR/Cas9 technology will be used to reverse-validate key resistance factors. This will serve as a foundation for the long-term discovery of companion diagnostics markers and the design of effective combination therapies.
With the global market for chronic lymphocytic leukemia (CLL) treatments expected to exceed $23 billion by 2030, there is an urgent need for new drugs for patients with double-refractory disease who have failed both conventional BTK inhibitors and Bcl-2 inhibitors. The REBELLE cohort study, led by Nantes University Hospital in France, will provide real-world genomic data to increase the clinical success rate of BTK degraders (BTKd), such as Nurix Therapeutics' (NURX) Bexobrutideg (Phase 2/3) and BeOne Medicines' BGB-16673 (Phase 3), which are in late-stage clinical trials. In particular, Nurix's recent $2.3 billion global co-development deal with Roche (RHHBY) demonstrates the high commercial value of the BTK degrader platform, and the patient biodata from this cohort will be used as key supporting data for future technology transfer and licensing deals by multinational pharmaceutical companies. In the medium to long term, CRISPR/Cas9 gene editing and organoid-based drug resistance studies will help reduce the failure rate of Phase 3 trials and serve as an important milestone for the development of companion diagnostic biomarkers, personalized treatment, and new combination therapies.
Source: ClinicalTrials.gov (api_ct)