What this Trial Is About

Adult acute lymphoblastic leukemia (ALL) includes Ph-positive (Phpos) ALL, Ph-negative (Phneg) B-cell precursor (BCP) ALL and T-ALL/lymphoblastic lymphoma (LL), accounting for approximately 25, 50 and 25% of all cases, respectively. In younger adults, the results associated with standard therapy have markedly improved in these 3 groups, due to chemotherapy intensification in the BCP and T groups and addition of TKIs in the Phpos group, respectively. This led to reevaluate the role of allogeneic hematopoietic stem cell transplantation (HSCT) in first remission, which is generally now indicated only in higher-risk patients, mostly defined as those with persistent high levels of minimal residual disease (MRD). Nevertheless, event-free survival (EFS) remains at 60-70% at 3 years, meaning there is still room for further improvements. Fortunately, new immunotherapies have been approved to treat relapsed/refractory (R/R) BCP-ALL patients, including the anti-CD19 bispecific T-cell engager blinatumomab (BLINA, Blincyto®, Amgen). 4 BLINA is also approved for the frontline treatment of patients with persistent high measurable residual disease (MRD) levels after initial therapy (IG/TR MRD ≥0.1% (≥1.10-3 )). BLINA has been also evaluated frontline in combination with TKI in the Phpos group leading to promising outcome improvements. Toxicities associated with these combined treatments seem to be limited and manageable. In the Phpos ALL subset, the third-generation tyrosine kinase inhibitor ponatinib (PONA, Iclusig®, Incyte) has also been evaluated frontline with promising results when compared to 1st or even 2nd generation TKI. In the T-ALL/LL subset, anti-CD38 antibodies, approved to treat patients with multiple myeloma, are potential drugs of interest. The anti-CD38 antibody isatuximab (ISA, Sarclisa®, Immunogen, Sanofi-Aventis) is currently approved to treat myeloma patients in 2nd line. In vitro and in vivo preclinical studies suggest that CD38 is a relevant target in T-ALL and that isatuximab may be useful to eradicate residual disease in this subgroup of patients. Incorporation/combination of these new agents into frontline adult ALL therapy could allow reducing relapse incidence and prolonging survival in these patients, challenging the indication for HSCT in first complete remission (CR). The present GRAALL-2024 study is a prospective multicenter multi-country 3-cohort randomized clinical trial. The 3 cohorts are : GRAALL-2024/B : Phneg BCP-ALL GRAAPH-2024 : Phpos ALL GRAALL-2024/T : T-ALL/LL Eligible patients will be allocated to one on the 3 study cohorts during a common treatment prephase. The primary objective of the study is to improve the outcome of younger adults with ALL through optimal frontline incorporation of new antibody-based therapies, including BLINA in Phneg/pos BCP-ALL patients and ISA in T-ALL/LL patients, and to refine indication for allogeneic HSCT in first remission in Phneg/pos BCP-ALL patients.

A 3-cohort Randomized Study Evaluating the Role of New Immunotherapeutic Agents and of Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) in Frontline Therapy of Adults With Acute Lymphoblastic Leukemia