A prospective open-label trial of long-acting liquid methylphenidate for the treatment of attention deficit/hyperactivity disorder in intellectually capable adults with autism spectrum disorder

World J Biol Psychiatry. 2020 Apr;21(4):274-290. doi: 10.1080/15622975.2019.1679392. Epub 2019 Dec 19.


Objectives: This treatment trial is aimed at assessing the short-term tolerability and efficacy of liquid-formulation extended-release methylphenidate (MPH-ER) for the treatment of attention deficit/hyperactivity disorder (ADHD) in adults with high-functioning autism spectrum disorder (HF-ASD).Methods: A 6-week open-label trial (ClinicalTrials.gov: NCT02096952) was conducted in 15 HF-ASD adults (mean age 24.9 ± 4.6; male, 12 (80%)) suffering from moderate-severe ADHD. MPH-ER was administered based on a flexible titration schedule. Efficacy was assessed on clinician- and self-rated measures. Tolerability was assessed by documenting treatment-emergent adverse events (AEs) and other safety measures.Results: Short-term MPH-ER treatment was associated with significant improvement in ADHD severity (Adult ADHD Investigator Symptom Report Scale (AISRS) mean change (MC), -22.8 ± 8.8, P < 0.001; Adult ADHD Self-Report Scale (ASRS) MC, -8.2 ± 15.3, P < 0.001). Twelve (80%) participants were deemed responders, based on ≥30% reduction in AISRS score and an ADHD Clinical Global Impression-Improvement score ≤2. MPH-ER was well-tolerated (treatment-limiting AEs, 1/15; severe AEs, 1/15) at mean dose of 48.7 ± 15 mg/day. AEs were transient and experienced by 13/15 (87%) participants at mild to moderate severity. Frequently reported AEs were as typically expected (headache (53%), insomnia (33%), anxiety (33%), decreased appetite (27%)).Conclusions: Our findings suggest that MPH-ER is effective and well-tolerated in the treatment of ADHD in HF-ASD adults.

Keywords: ADHD; ASD; methylphenidate; open-label; psychopharmacology.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Attention Deficit Disorder with Hyperactivity* / complications
  • Attention Deficit Disorder with Hyperactivity* / drug therapy
  • Autism Spectrum Disorder* / complications
  • Central Nervous System Stimulants* / adverse effects
  • Central Nervous System Stimulants* / therapeutic use
  • Delayed-Action Preparations / therapeutic use
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Methylphenidate* / adverse effects
  • Methylphenidate* / therapeutic use
  • Prospective Studies
  • Treatment Outcome
  • Young Adult


  • Central Nervous System Stimulants
  • Delayed-Action Preparations
  • Methylphenidate

Associated data

  • ClinicalTrials.gov/NCT02096952