{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T13:22:43Z","timestamp":1791206563981,"version":"4.1.0"},"reference-count":23,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Psychiatry"],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>This study examined the 52-week safety and efficacy of AST-001 syrup for the core symptoms of autism spectrum disorder (ASD) in children aged 2\u201311 years.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This multicenter long-term follow-up study enrolled children with ASD who were identified as responders in an antecedent phase II randomized controlled trial. A total of 61 participants were given the same dose (high or low) they received during the extension phase of the phase-II trial for 52 weeks. Safety and tolerability were evaluated by reporting adverse events. Efficacy was assessed using the Ohio State University Autism Clinical Global Impression (CGI)-Severity and Improvement scale.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The proportion of participants experiencing any treatment-emergent adverse events was 40.98%, most commonly due to COVID-19 (11\/61 participants, 18.03%), but none were related to AST-001. Two participants experienced adverse drug reactions (2\/61 participants, 3.28%), including decreased appetite and enteritis. The incidence of serious adverse events was 4.92% (3\/61 participants), which were dental caries, otitis media, and septic shock, but none were related to medication. The mean CGI-S score decreased slightly from 4.25 \u00b1 0.87 at baseline to 4.10 \u00b1 0.79 at week 52 of the long-term follow-up study. Among the 48 participants who were CGI-I responders at week 24 of phase-II trial, 45 continued to meet the responder criteria at week 52.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>AST-001 was well tolerated over the 52-week period, and clinical improvement was maintained among participants who had previously responded to treatment, suggesting continued benefit on ASD core symptoms. These findings provide preliminary long-term data on safety, tolerability, and clinical outcomes in a field where pharmacologic treatment options for the core symptoms of ASD remain limited. However, given the uncontrolled long-term follow-up design in prior responders, the results should be interpreted with caution and do not constitute confirmatory evidence of sustained efficacy. Further large-scale, well-controlled studies are warranted.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical Trial Registration<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link>https:\/\/cris.nih.go.kr\/cris\/search\/detailSearch.do?seq=26492&amp;amp;search_page=L&amp;amp;search_lang=&amp;amp;class_yn=<\/jats:ext-link>\n                      , identifier KCT0007519.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpsyt.2026.1783915","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T05:24:45Z","timestamp":1780291485000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Safety and efficacy of AST-001 in children with autism spectrum disorder: a 52-week multicenter long-term follow-up study"],"prefix":"10.3389","volume":"17","author":[{"given":"Johanna Inhyang","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Psychiatry, Hanyang University College of Medicine","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyo-Won","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, University of Ulsan College of Medicine, Asan Medical Center","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji-Hoon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Pusan National University Yangsan Hospital","place":["Yangsan, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"MoonSoo","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Korea University, College of Medicine","place":["Seoul, Republic of 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