Abstract
BACKGROUND AND AIMS: No effective pharmacotherapy for methamphetamine (MA) use disorder has yet been found. This study evaluated sustained-release methylphenidate (MPH-SR) compared with placebo (PLA) for treatment of MA use disorder in people also undergoing behavioral support and motivational incentives. DESIGN: This was a randomized, double-blind, placebo-controlled design with MPH-SR or PLA provided for 10 weeks (active phase) followed by 4 weeks of single-blind PLA. Twice-weekly clinic visits, weekly group counseling (CBT) and motivational incentives (MI) for MA-negative urine drug screens (UDS) were included. SETTING: Treatment sites were in Los Angeles, California (LA) and Honolulu, Hawaii (HH), USA. PARTICIPANTS: A total of 110 MA-dependent (via DSM-IV) participants (LA = 90; HH = 20). MEASUREMENTS: The primary outcome measure is self-reported days of MA use during the last 30 days of the active phase. Included in the current analyses are drug use (UDS and self-report), retention, craving, compliance (dosing, CBT, MI), adverse events and treatment satisfaction. FINDINGS: No difference was found between treatment groups in self-reported days of MA use during the last 30 days of the active phase (P = 0.22). In planned secondary outcomes analyses, however, the MPH group had fewer self-reported MA use days from baseline through the active phase compared with the PLA group (P = 0.05). The MPH group also had lower craving scores and fewer marijuana-positive UDS than the PLA group in the last 30 days of the active phase. The two groups had similar retention, other drug use, adverse events and treatment satisfaction. CONCLUSIONS: Methylphenidate may lead to a reduction in concurrent methamphetamine use when provided as treatment for patients undergoing behavioral support for moderate to severe methamphetamine use disorder, but this requires confirmation.