A phase 2 study of sorafenib combined with conventional therapies in refractory central nervous system leukemia.

BACKGROUND

Patients with refractory central nervous system leukemia (CNSL) have a dismal prognosis and lack effective therapy. Case reports have shown that sorafenib is effective against brain metastases, including leukemia.

METHODS

To explore the efficacy of sorafenib combined with conventional therapies for refractory CNSL, a phase 2 study was conducted. The primary end point was the complete remission rate (CRR) within 8 weeks of treatment. Secondary end points included the overall response rate (ORR), event-free survival (EFS), overall survival (OS), and adverse events (AEs).

RESULTS

Twenty-six patients with refractory CNSL were enrolled; they included 17 with isolated CNSL, 7 with hematological relapse, and 2 with another extramedullary relapse. After 8 weeks of treatment, 21 patients achieved complete remission, 2 achieved partial remission, and 3 achieved no remission for a CRR of 80.8% (95% CI, 62.1%-91.5%) and an ORR of 88.5% (95% CI, 71.0%-96.0%). Twenty patients survived, and 6 died. The 2-year EFS and OS rates were 75.0% (95% CI, 54.5%-88.3%) and 76.9% (95% CI, 54.2%-90.4%), respectively. Six patients experienced grade 3 or 4 treatment-related AEs, including moderate chronic graft-vs-host disease (n = 3), grade 3 or 4 acute graft-vs-host disease (n = 2), and grade 3 skin rash (n = 1). No treatment-related deaths occurred during the therapy of refractory CNSL.

CONCLUSIONS

Sorafenib combined with conventional therapies is effective and safe for refractory CNSL.

LAY SUMMARY

Sorafenib combined with conventional therapies is effective and safe for refractory central nervous system leukemia.