{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T20:57:14Z","timestamp":1788209834896,"version":"build-2803163510"},"reference-count":56,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Background\/Objectives: Proteolysis Targeting Chimeras (PROTACs) are heterobifunctional small molecules that induce ubiquitin\u2013proteasome\u2013mediated degradation of target proteins and have matured from proof-of-concept chemistry to a clinically validated therapeutic modality, with the first Phase 3 readout reported in 2025. A systematic bibliometric analysis covering this pivotal-trial era, however, has been lacking. This study aimed to map the historical trajectory, current research front, and emerging frontiers of PROTAC research. Methods: We analyzed 2630 PROTAC-related publications indexed in the Web of Science Core Collection (WoSCC) from 2001 to 2025 using a combined toolkit of CiteSpace, HistCite, the Alluvial Generator, and R (ggplot2), covering co-occurrence networks, burst detection, keyword clustering, citation historiography, alluvial flow analysis, and reference co-citation timeline visualization. Results: China and the USA led global output, and the Chinese Academy of Sciences, China Pharmaceutical University, and Harvard University were the most productive institutions; the Journal of Medicinal Chemistry was the leading publishing venue, and Alessio Ciulli, Jian Jin, and Craig M. Crews anchored the author network. Keyword burst analysis showed that early research centred on E3 ubiquitin ligase recruitment and small-molecule PROTAC design, whereas the current hotspots, resolved through keyword clustering and co-citation timelines, included structural basis and ternary complex design, EGFR-directed degradation, oral bioavailability optimization, applications in multiple myeloma and Alzheimer\u2019s disease, tumour-targeted delivery, and computational\/AI-driven design. Conclusions: This study extends the bibliometric record of PROTACs across 2001\u20132025 and identifies oral bioavailability, E3 ligase repertoire expansion, and CNS-penetrant degrader design as the emerging frontiers likely to shape the next phase of the field.<\/jats:p>","DOI":"10.3390\/ph19070988","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T16:50:33Z","timestamp":1782924633000},"page":"988","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Research Trends and Emerging Frontiers in Proteolysis Targeting Chimeras (PROTACs): A Bibliometric Analysis of 2630 Publications (2001\u20132025)"],"prefix":"10.3390","volume":"19","author":[{"given":"Ganglin","family":"Su","sequence":"first","affiliation":[{"name":"Department of Urology, Peking University First Hospital, Peking University, Beijing 100034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yihan","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Urology, Peking University First Hospital, Peking University, Beijing 100034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Yao","sequence":"additional","affiliation":[{"name":"Department of Urology, Peking University First Hospital, Peking University, Beijing 100034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8554","DOI":"10.1073\/pnas.141230798","article-title":"Protacs: Chimeric molecules that target proteins to the Skp1-Cullin-F box complex for ubiquitination and degradation","volume":"98","author":"Sakamoto","year":"2001","journal-title":"Proc. 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