Alectinib in children and adolescents with solid or CNS tumors harboring ALK-fusions: Data from the iMATRIX Alectinib Phase I/II open-label, multi-center study

According to the data presented at the AACR 2024 conference, as of the data cutoff date of June 12, 2023, a total of 8 patients at a median age of 11 years diagnosed with inflammatory myofibroblastic tumor (n=2), high-grade glioma (n=3), renal cell carcinoma (n=2), and anaplastic large cell lymphoma (n=1, protocol deviation) were enrolled. Among 7 patients evaluable for efficacy, 6 had not received prior systemic therapy. Furthermore, the ALK fusion partners were KIF5C in 2 patients and TPM3, CLTC, PLEKHA7, DCTN1, and HNRNPA3 in 1 patient each. Apart from that, the median treatment duration was 12 months, and no dose-limiting toxicities were reported.

Investigators reported the Best Overall Responses as follows: in 4 patients (57.1%; 1 CR, 3 PR), 2 patients (28.6%) with Stable Disease, and 1 patient had not undergone a tumor assessment at the time of data cut-off. In terms of safety, 7 patients experienced a related Adverse Event (AE) including 2 patients with Grade ≥ 3 related AE. There were no AE-related deaths, and no new safety signals were detected.

Conclusion

In pediatric patients with ALK-fusion positive solid or CNS tumors, alectinib exhibits promising efficacy alongside favorable tolerability, offering hope in this challenging population with the majority of patients responding positively, thus presenting a compelling benefit-risk profile.