A set of novel chemotherapy regimens yield excellent outcomes—the best yet—among pediatric and young adult patients with T-cell malignancies, finds a phase 3 randomized controlled trial conducted by the Children’s Oncology Group (ALL0434).
“Despite very intense and complex chemotherapy, 20% of children and adolescents enrolled in Children’s Oncology Group T-cell leukemia trials between 2000 and 2005 did not survive. New drugs were needed to improve survival rates for T-cell malignancies,” lead study author Kimberly P. Dunsmore, MD, a professor at Virginia Tech, Roanoke, said in a press briefing leading up to the annual meeting of the American Society of Clinical Oncology.
The ALL0434 trial tested the addition of methotrexate (Trexall) and/or nelarabine (Arranon), a T cell–specific drug known to be efficacious in relapsed disease, to standard chemotherapy, with tailoring of the regimen to recurrence risk. Analyses were based on 1,545 patients with T-cell acute lymphoblastic leukemia (T-ALL) or T-cell lymphoblastic lymphoma (T-LL).
Results for all patients with T-ALL showed that, with addition of either or both drugs, more than 90% were alive at 4 years and more than 80% were leukemia free. Adding nelarabine to standard chemotherapy improved disease-free survival among the subset having intermediate- or high-risk disease, and the best outcomes were seen with addition of both nelarabine and an escalating dose of methotrexate.
Although patients with T-LL did not see benefit from addition of nelarabine, they still had an 85% rate of overall survival at 4 years.
“ALL0434 is the largest trial for children and young adults with T-cell malignancy ever conducted. It has the best-ever survival data,” Dr. Dunsmore commented.
“Our next steps will be to examine what implications and benefits may accrue when using nelarabine in protocols without cranial irradiation. This is to decrease long-term neurologic side effects, and we think it may be possible since nelarabine also reduces CNS relapses,” she said.