Haematology-Oncology · Clinical trials
Chronic Lymphocytic Leukaemia (CLL) Clinical Trials
Approved therapies, the pivotal-trial endpoints they were judged on, the magnitude of benefit — and the drugs that failed their endpoints, and why.
Indication overview
About chronic lymphocytic leukaemia (cll) — and why its trials are hard
Chronic lymphocytic leukaemia is the most common adult leukaemia in Western countries, characterised by accumulation of mature-appearing but dysfunctional CD5+/CD19+ B lymphocytes in blood, marrow and lymphoid tissue. Many patients are diagnosed incidentally and observed until symptomatic (progressive cytopenias, bulky nodes, constitutional symptoms). Prognosis is shaped by IGHV mutation status, TP53 aberrations (del(17p)/TP53 mutation) and cytogenetics. Management has shifted almost entirely from chemoimmunotherapy to targeted oral agents. Covalent BTK inhibitors transformed care: ibrutinib (RESONATE) and the more selective acalabrutinib (ELEVATE) and zanubrutinib (ALPINE) offer durable disease control with continuous dosing. The BCL2 inhibitor venetoclax, combined with the anti-CD20 antibody obinutuzumab (CLL14), enables fixed-duration, time-limited therapy achieving deep MRD-negative remissions. TP53-aberrant disease responds poorly to chemotherapy, making targeted agents essential. Richter transformation to aggressive lymphoma remains a feared complication with limited options. Choice among agents is increasingly driven by comorbidities, cardiovascular risk and patient preference for continuous versus fixed-duration treatment.
Approved therapies & pivotal evidence
What's been approved — and by how much it moved the endpoint
| Drug (brand) | Approved | Setting | Pivotal trial | Primary endpoint | Magnitude of benefit |
|---|---|---|---|---|---|
| Ibrutinib (Imbruvica) | 2014 | Relapsed/refractory, then frontline CLL | RESONATE | Progression-free survival / overall survival | Marked PFS improvement vs ofatumumab (PFS HR ~0.22) with OS benefit |
| Acalabrutinib (Calquence) | 2019 | Frontline and relapsed/refractory CLL | ELEVATE-TN (frontline); ELEVATE-RR (vs ibrutinib) | Progression-free survival; non-inferiority with fewer cardiac events | Superior PFS vs chemoimmunotherapy; ELEVATE-RR non-inferior to ibrutinib with less atrial fibrillation |
| Venetoclax + obinutuzumab (Venclexta + Gazyva) | 2019 | Frontline CLL (fixed 12-month duration) | CLL14 | Progression-free survival / MRD negativity | Superior PFS vs obinutuzumab-chlorambucil with high rate of undetectable MRD |
| Zanubrutinib (Brukinsa) | 2023 (CLL/SLL) | Frontline and relapsed/refractory CLL/SLL | ALPINE (vs ibrutinib); SEQUOIA (frontline) | Overall response rate / progression-free survival | ALPINE showed superior PFS and fewer cardiac events vs ibrutinib |
| Venetoclax (Venclexta) | 2016 | Relapsed/refractory, including del(17p) | M13-982; MURANO (with rituximab) | Overall response rate; PFS | High ORR in del(17p); MURANO PFS strongly favoured venetoclax-rituximab |
Where trials have failed
Drugs that missed their endpoint — and what contributed
The most instructive lessons in chronic lymphocytic leukaemia (cll) development come from programmes that failed the endpoint that mattered.
| Drug / trial | Endpoint outcome | What contributed |
|---|---|---|
| Idelalisib — Multiple frontline combination trials (halted) | Frontline development was curtailed after serious/fatal toxicities (severe hepatotoxicity, colitis/diarrhoea, pneumonitis and opportunistic infections) | Immune-mediated and infectious toxicity led FDA safety warnings and withdrawal of several indications; largely displaced by safer BTK and BCL2 inhibitors |
Choosing the right endpoint
Primary endpoints that matter in chronic lymphocytic leukaemia (cll) trials
- Progression-free survival (PFS) — Primary endpoint across modern CLL trials
- Undetectable MRD (uMRD) — Key depth marker enabling fixed-duration therapy decisions, especially with venetoclax combinations
- Overall response rate (ORR) — Per iwCLL criteria; includes lymphocytosis resolution considerations for BTK inhibitors
- Overall survival (OS) — Harder to demonstrate given effective cross-over and later lines
- Time to next treatment — Patient-relevant measure of durability, particularly for fixed-duration regimens
How iNGENū runs chronic lymphocytic leukaemia (cll) trials
Physician-led design, built for FDA submission
Endpoint & biomarker strategy
Board-certified specialists design endpoints and patient selection aligned to current FDA guidance for this indication.
FDA-ready data
Built to ICH-GCP and 21 CFR 312.120, with direct FDA submission — data accepted by the FDA, EMA and MHRA.
Faster, lower-cost delivery
~4-week ethics via the TGA CTN scheme, up to 43.5% R&D rebate, and 80–90% below US CRO cost.
Request a fixed-milestone proposal and a tailored endpoint & feasibility summary for this indication.
Frequently asked questions
Chronic Lymphocytic Leukaemia (CLL) clinical trials — FAQs
Do all CLL patients need immediate treatment?
Why does TP53/del(17p) status matter?
Continuous versus fixed-duration therapy?
Ready to discuss your chronic lymphocytic leukaemia (cll) trial?
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