NCT03553875.

Study name	Memantine for the treatment of social deficits in youth with disorders of impaired social interactions
Methods	12‐week parallel trial of memantine hydrochloride versus placebo
Participants	Inclusion criteria: male or female participants aged 8‐18 years DSM‐V diagnosis of ASD, and "at least moderate severity of social impairment as measured by a total raw score of ≥85 on the parent/guardian‐completed Social Responsiveness Scale‐Second Edition (SRS‐2)14 and a score of ≥4 on the clinician‐administered Clinical Global Impression‐Severity scale (CGI‐S)17" Exclusion criteria: IQ < 70 currently taking lamatrogine, amantadine, N‐Acetycysteine, or D‐cycloserine any other psychotropics that have not been stable for past 4 weeks co‐administration of drugs that compete with memantine such as hydrochlorothiazide, triamterene, metformin, cimetidine, ranitidine, quinidine, and nicotine pregnant or breastfeeding; history of or current liver or kidney disease serious medical conditions known hypersensitivity to memantine Location/setting: Massachusetts General Hospital, USA Target sample size: 100 participants
Interventions	Intervention (memantine) for 12 weeks: maximum daily dose of 20 mg, administered twice daily for 12 weeks Comparator (placebo) for 12 weeks: equivalent placebo pill twice daily
Outcomes	Primary outcomes: CGI‐Improvement Scale Secondary outcomes: unclear Timing of outcome assessments: not known
Starting date	First registered in November 2018
Contact information	Name: Chloe Hutt Vater E‐mail: chuttvater@mgh.harvard.edu
Notes	Source of funding: Massachusetts General Hospital Conflicts of interest: unclear