Stem Cell Therapy for Autism Spectrum Disorder: A Systematic Review and Meta-Analysis of Clinical Evidence
S. M. M. Fekrat, V. Sharma, S. Prasad, S. GunturuIntroduction
Autism spectrum disorder (ASD) affects approximately 1 in 36 children globally, with limited evidence-based treatments addressing core symptomatology. The emerging regenerative medicine approaches using stem cell therapy have shown potential for modulating neuroinflammation and enhancing neuroplasticity in neurodevelopmental conditions. However, the clinical efficacy and safety profile of stem cell interventions for ASD remains uncertain.
Objectives
This study aims to perform a systematic review and meta-analysis of clinical studies evaluating the efficacy and safety of stem cell therapy in children with autism spectrum disorder, as well as to identify optimal treatment protocols and patient selection criteria.
Methods
A comprehensive systematic review was conducted in accordance with the PRISMA guidelines across multiple databases (PubMed, Scopus, PsycINFO) on September 17, 2025, yielding a total of 1,698 records (Figure 1). After removing 399 duplicates, the remaining 1299 records were screened based on title, abstract, and full-text analysis. Inclusion criteria: (1) randomized controlled trials, controlled clinical trials, and open-label studies; (2) participants diagnosed with ASD using standardized criteria (DSM-5, ADOS, ADI-R); (3) stem cell interventions (mesenchymal stem cells, umbilical cord blood, neural stem cells); (4) standardized outcome measures. Exclusion criteria: preclinical studies, case reports, and non-English publications. Two independent reviewers conducted data extraction and quality assessment (Risk of Bias). Cochrane RevMan 5.4 was used for meta-analysis.
Results
All 22 studies demonstrated the efficacy of stem cell therapy in the treatment of ASD. Autism Spectrum Disorder was diagnosed according to the DSM-5 TR criteria. The Childhood Autism Rating Scale (CARS), Autism Treatment Evaluation Checklist (ATEC), Vineland Adaptive Behavior Scales (VABS), Aberrant Behavior Checklist (ABC), and Pervasive Developmental Disorder Behavior Inventory T-score (PDDBI) were used to evaluate autism at various durations during clinical trials. A statistically significant overall improvement in ASD was seen post-treatment with stem cells, on meta-analysis, with a pooled standard mean difference (SMD) of -1.03 [95% CI (-1.23, -0.83), Z=10.03, p<0.00001] but with high heterogeneity (I2= 95%) (Figure 2). Few studies also found stem cell therapy to be more effective than placebo, with SMD of -4.99 [95% CI (-8.11, -1.88), Z=3.14, p=0.002] with low heterogeneity (I2=0%) (Figure 3).
Image 1: Long description.