Regimen of single-agent arsenic trioxide. Arsenic trioxide was administered intravenously at a dose of 10 mg for adults and 0.15 mg/kg for pediatric patients until CR. Another 4-week course (consolidation) was administered after a 4-week interval for those achieving CR. Subsequently, after a second 4-week interval it was administered for 10 days/month for 6 months (maintenance).