The following is the summary of “Effect of therapeutic drug monitoring of risperidone and aripiprazole on weight gain in children and adolescents: the SPACe 2: STAR (trial) protocol of an international multicentre randomised controlled trial” published in the December 2022 issue of Psychiatry by Hermans, et al.

Children on the autism spectrum often display irritability and violence, and antipsychotic medicines play a crucial role in managing these symptoms (ASD). However, antipsychotic treatment in children is associated with clinically important side effects including considerable weight gain and metabolic abnormalities. Their results from the SPACe trial demonstrated that both risperidone and aripiprazole plasma trough concentrations were positively correlated with weight increase during a 6-month period. Therapeutic medication monitoring in clinical practice may prevent excessive weight gain while maintaining clinical effectiveness, which is the goal of the follow-up study SPACe 2: STAR.

SPACe 2: STAR is a multinational, randomized controlled trial (RCT). Forty children, ages 6-18, who will soon begin treatment with risperidone or aripiprazole for behavioral issues related to autism spectrum disorder (ASD) will be randomly assigned to either a therapeutic drug monitoring (TDM) group or a care as usual (CAU) group. Following 4, 10, 24, and 52 weeks, participants will be re-evaluated. If a patient is in the TDM group, their doctor will be given recommendations for dose every 4 and 10 weeks based on measurements of plasma levels of risperidone, aripiprazole, and its metabolites. Dried blood spots will be used to determine plasma concentration (DBS). 

After 24 weeks of antipsychotic medication, the primary outcome will be the change in body mass index (BMI) z-score. Quality of life, the number of extrapyramidal symptoms experienced, and the levels of prolactin, leptin, and ghrelin are all secondary outcomes. When completed, this randomized controlled trial will be the first to examine the efficacy of TDM for antipsychotics in young people. As a result, the results of SPACe 2: STAR will be extremely helpful in determining how to best care for this vulnerable population.