Coenzyme Q10, Vitamin E and Polyvitamin B: an exploratory double-blind randomized cross-over study in Phelan-McDermid Syndrome

Aim: Defective mitochondrial function and increased oxidative stress have been documented in Autism Spectrum Disorder (ASD) and Phelan-McDermid syndrome (PMS), one of the best-known monogenic forms of ASD. The purpose of this exploratory, double-blind, randomized cross-over trial (RCT) is to verify the efficacy and safety of a “metabolic support therapy” (MST) in PMS, while defining the experimental methodology most apt at maximizing sensitivity and reliability. Methods: A total of 31 PMS patients completed 4 months of Coenzyme Q10 (50/100 mg b.i.d.) + vitamin E (30/60 mg/d) + polyvitamin B ("active compound") vs. 4 months of only Vitamins E and B ("active comparator"). To explore their sensitivity and reliability, four primary outcome measures were used: VABS, CARS, CGI-I, and VAS. Secondary outcome measures span adaptive behaviors, social cognition, autism, problem behaviors, quality of life (QoL), communication, and comorbidities. Results: CoQ10+vit. E and B yielded significantly greater improvement in several measures of cognition and adaptive functioning, motor skills, and stereotypic behaviors compared to vit. E and B only. Maternal QoL was especially improved in the presence of CoQ10 (P < 0.004). Time x Treatment interactions in CGI-I and VAS "restricted interests" scores support positive contributions also by vitamins E and B. Side effects, including hyperactivity, insomnia, and irritability, were mild, rare, and did not differ between treatment periods. Conclusion: MST may produce small-to-moderate improvement, especially in motor skills, social motivation, adaptive behaviors, responsiveness to environmental stimulation, and stereotypic behaviors in up to approximately 70% of PMS patients. A targeted confirmatory RCT contrasting Q10+vit E and B vs. inactive placebo is now warranted.