Background
Phase 2, multicenter, single-arm trial (GIMEMA LAL1205). N=53 evaluable patients with newly diagnosed Philadelphia-positive (Ph+) ALL, age ≥18 with no upper age limit (median 53.6 years). First prospective evaluation of dasatinib monotherapy (without a cytotoxic chemotherapy backbone) as induction for Ph+ ALL, demonstrating that a TKI alone could achieve high complete haematologic response rates and paving the way for chemotherapy-free strategies. Published Blood 2011.
Interventions and follow up
Regimen: Dasatinib 70 mg PO twice daily + prednisone 60 mg/m²/d (steroid prephase days 1–32, tapered); no chemotherapy induction, newly diagnosed adult Ph+ ALL
Primary endpoint: Complete haematologic response (CHR) rate at day 22 (end of steroid phase)
Median follow-up: 20 months
Primary endpoint: Complete haematologic response (CHR) rate at day 22 (end of steroid phase)
Median follow-up: 20 months
Results
CHR at day 22 (primary): 92.5% (49/53; 95% CI 81.8–97.9)
Overall CHR by end of induction: 100% (53/53)
Complete molecular response (BCR-ABL ≤10⁻⁴): 8/53 (15%) — limited molecular depth
MRD response (BCR-ABL <10⁻³ at day 22): Predicted superior DFS, P=.017; defines a high-risk MRD-positive subgroup needing intensification
20-month OS: 69.2%
20-month DFS: 51.1%
Overall CHR by end of induction: 100% (53/53)
Complete molecular response (BCR-ABL ≤10⁻⁴): 8/53 (15%) — limited molecular depth
MRD response (BCR-ABL <10⁻³ at day 22): Predicted superior DFS, P=.017; defines a high-risk MRD-positive subgroup needing intensification
20-month OS: 69.2%
20-month DFS: 51.1%
Adverse events
Dasatinib-related (grade ≥3): Pleural effusion ~8%, fluid retention, cytopenias; well tolerated even in elderly patients
Steroid/other: Prednisone-related hyperglycemia and infections; no chemotherapy-type toxicities (nausea, alopecia, mucositis) and no treatment-related deaths — favorable for older/frail patients
Steroid/other: Prednisone-related hyperglycemia and infections; no chemotherapy-type toxicities (nausea, alopecia, mucositis) and no treatment-related deaths — favorable for older/frail patients
Conclusions
Dasatinib + steroid induction achieved 100% CHR in newly diagnosed Ph+ ALL across all ages without cytotoxic chemotherapy — the first demonstration that a TKI-only induction strategy was effective and feasible. MRD response at day 22 was prognostically significant and identified patients needing more aggressive post-induction therapy.
Key Limitations
Single-arm, non-randomized design with no chemotherapy comparator. Shallow molecular responses (only 15% CMR) and high relapse risk meant durable disease control still required consolidation/transplant or more potent TKIs. Short follow-up (20 months) and modest sample (N=53). Predates ponatinib and blinatumomab-based chemo-free strategies; durable remissions were not achievable with dasatinib monotherapy alone, foreshadowing later combination approaches (D-ALBA).
Clinical Context
GIMEMA LAL1205 was a landmark proof-of-concept that TKI-based induction without chemotherapy can induce remission in Ph+ ALL, particularly valuable for elderly and unfit patients. It established the conceptual foundation for chemotherapy-free Ph+ ALL regimens later realized with dasatinib-blinatumomab (D-ALBA) and ponatinib-based approaches. ESMO and ELN frameworks recognize TKI-anchored induction as central to Ph+ ALL management; this trial was an early driver of that shift.
References