In Phase 3, Ponatinib/Blinatumomab Improves EFS in Ph+ ALL

A chemotherapy-free regimen of ponatinib (Iclusig), a third-generation tyrosine kinase inhibitor (TKI), plus blinatumomab (Blincyto), a CD19-directed CD3 T-cell engager, significantly improved event-free survival (EFS) compared with imatinib (Gleevec) plus chemotherapy in adults with newly diagnosed Philadelphia chromosome–positive acute lymphoblastic leukemia (Ph+ ALL), according to findings from the phase 3 GIMEMA ALL2820 trial (NCT04722848) published in the New England Journal of Medicine.¹

At a median follow-up of 23.7 months, the estimated 24-month EFS rate was 86% (95% CI, 80%-92%) with ponatinib plus blinatumomab vs 67% (95% CI, 56%-79%) with imatinib plus chemotherapy (P < .001). The chemotherapy-free regimen also demonstrated higher molecular EFS, complete hematologic response rates, and molecular response rates following consolidation.

The findings provide randomized phase 3 evidence that a chemotherapy-free regimen can outperform a TKI plus chemotherapy as frontline treatment for adults with Ph+ ALL, and they strengthen the case for moving away from chemotherapy-based induction, though longer follow-up is needed to confirm durability.

Study Design

The open-label, randomized phase 3 GIMEMA ALL2820 trial enrolled 236 adults with newly diagnosed Ph+ ALL. Patients were randomly assigned in a 2:1 ratio to receive either ponatinib plus blinatumomab (n = 158) or imatinib plus chemotherapy (n = 78). The median patient age was 55 years (range, 24-82).

Patients in the experimental group received ponatinib during induction, followed by at least 2 cycles of blinatumomab, with ponatinib continued during consolidation and subsequent treatment. Patients in the control group received imatinib combined with 4 to 6 cycles of age-adjusted chemotherapy. Crossover to ponatinib plus blinatumomab was permitted for patients in the control group with persistent or recurrent measurable residual disease (MRD).

The primary end point was EFS, which included events such as failure to achieve complete molecular response, toxic effects, treatment resistance, and death. Molecular EFS, complete hematologic response, molecular response, overall survival (OS), and relapse incidence were also evaluated.

Efficacy Outcomes Favor Ponatinib Plus Blinatumomab

In addition to the EFS improvement, molecular EFS was 68% with ponatinib plus blinatumomab vs 42% with imatinib plus chemotherapy. Complete hematologic response rates at the end of induction were also higher with the experimental regimen (94% vs 79%).

Molecular response rates were similar between treatment groups at the end of induction, at 47% with ponatinib plus blinatumomab and 44% with imatinib plus chemotherapy. Following consolidation, molecular response rates increased to 71% with ponatinib plus blinatumomab compared with 49% with imatinib plus chemotherapy. Among 31 patients who crossed over from the control group to receive ponatinib plus blinatumomab, 20 (64%) subsequently achieved a molecular response.

The cumulative incidence of relapse was 5% with ponatinib plus blinatumomab compared with 13% with imatinib plus chemotherapy. The estimated 24-month OS rate was 90% in the experimental group and 85% in the control group.

The use of allogeneic hematopoietic stem cell transplantation was also relatively limited in the experimental group. Among patients who achieved a first complete hematologic response, 19% of those receiving ponatinib plus blinatumomab underwent transplantation compared with 26% of patients receiving imatinib plus chemotherapy.

Safety and Cardiovascular Events With Ponatinib

Grade 3 or higher adverse events occurred in 34% of patients receiving ponatinib plus blinatumomab compared with 47% of those receiving imatinib plus chemotherapy. Infections were the most common severe adverse events in both groups. Cardiovascular and vascular events, a known safety concern associated with ponatinib, were uncommon and occurred only among patients who received the 45-mg dose. Patients experiencing these events were a median age of 72 years.¹^,²

Deaths during induction occurred in 4 patients (3%) in the ponatinib-plus-blinatumomab group compared with 7 patients (9%) in the control group.

Ponatinib received FDA accelerated approval in March 2024 in combination with chemotherapy for adults with newly diagnosed Ph+ ALL, based on MRD-negative complete remission rates in the phase 3 PhALLCON trial (NCT03589326). Blinatumomab is approved for several B-cell precursor ALL indications, including MRD-positive disease and relapsed or refractory disease. The GIMEMA ALL2820 findings provide phase 3 evidence supporting the combination of these agents as a chemotherapy-free frontline approach; the trial did not evaluate an FDA-approved indication for the combination.³^˒⁴

The investigators noted that the relatively short follow-up period and open-label trial design were limitations of the study. Longer follow-up will be important to further characterize the durability of responses and survival outcomes.

“In this phase 3 trial, we documented the superiority of a frontline chemotherapy-free targeted and immunotherapeutic approach over conventional treatment in adult patients with Ph+ ALL,” investigators Chiaretti et al wrote.¹

REFERENCES

1. Chiaretti S, Piciocchi A, Skert C, et al. Ponatinib–blinatumomab or imatinib–chemotherapy for adult Ph-positive ALL. N Engl J Med. 2026;395(15):1483-1494. doi:10.1056/NEJMoa2606208

2. Barbor M. Ponatinib/blinatumomab improves event-free survival in Ph-positive ALL. The ASCO Post. November 6, 2026. Accessed November 9, 2026. https://tinyurl.com/y6yprkmm

3. FDA grants accelerated approval to ponatinib with chemotherapy for newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia. FDA. March 19, 2024. Accessed November 9, 2026. https://tinyurl.com/383xssxr

4. BLINCYTO. Prescribing information. Amgen Inc. Accessed November 9, 2026. https://tinyurl.com/3vj2eh73