{"id":1293,"date":"2025-09-25T15:50:00","date_gmt":"2025-09-25T13:50:00","guid":{"rendered":"https:\/\/lensounds.com\/science\/first-in-human-study-of-211atnaat-as-targeted-%ce%b1-therapy-in-patients-with-radioiodine-refractory-thyroid-cancer-alpha-t1-trial\/"},"modified":"2025-09-25T15:50:00","modified_gmt":"2025-09-25T13:50:00","slug":"first-in-human-study-of-211atnaat-as-targeted-%ce%b1-therapy-in-patients-with-radioiodine-refractory-thyroid-cancer-alpha-t1-trial","status":"publish","type":"science","link":"https:\/\/atonco-pharma.com\/en\/science\/first-in-human-study-of-211atnaat-as-targeted-%ce%b1-therapy-in-patients-with-radioiodine-refractory-thyroid-cancer-alpha-t1-trial\/","title":{"rendered":"First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial)"},"content":{"rendered":"<h2>Abstract<\/h2>\n<p>This first-in-human study examined the safety and therapeutic potential of [\u00b2\u00b9\u00b9At]NaAt, a novel alpha-particle therapy using astatine-211, in eleven patients with radioiodine-refractory differentiated thyroid cancer (DTC). The study employed a modified 3+3 dose-escalation design with doses of 1.25, 2.5, and 3.5 MBq\/kg. Dose-limiting toxicities (DLTs) consisting of grade 3 leukopenia and lymphopenia were observed in 50% of patients at the 3.5 MBq\/kg dose. Non-hematologic adverse events included transient salivary gland swelling, nausea, and gastrointestinal effects, predominantly at doses \u22652.5 MBq\/kg. Remarkably, hematologic toxicities were transient with complete recovery by 8 weeks. Therapeutic efficacy assessment showed \u226550% thyroglobulin reduction in 33% of patients at both 2.5 and 3.5 MBq\/kg doses. At 6 months, 90% of patients achieved stable disease, with partial or complete responses observed on [\u00b9\u00b3\u00b9I]SPECT imaging. The recommended Phase 2 dose was determined to be 2.5 MBq\/kg based on the favorable tolerability profile and preliminary evidence of therapeutic benefit. This study provides the first clinical evidence that [\u00b2\u00b9\u00b9At]NaAt is a safe and effective treatment option for RAI-refractory thyroid cancer.<\/p>\n<h2>Publication Information<\/h2>\n<p><strong>Journal:<\/strong> Journal of Nuclear Medicine<\/p>\n<p><strong>Publication Type:<\/strong> Early Online Publication<\/p>\n<p><strong>Publication Date:<\/strong> September 25, 2025<\/p>\n<p><strong>DOI:<\/strong> 10.2967\/jnumed.125.270810<\/p>\n<p><strong>Journal Link:<\/strong> <a href=\"https:\/\/jnm.snmjournals.org\/content\/early\/2025\/09\/25\/jnumed.125.270810\" target=\"_blank\" rel=\"noopener\">https:\/\/jnm.snmjournals.org\/content\/early\/2025\/09\/25\/jnumed.125.270810<\/a><\/p>\n<h2>Authors<\/h2>\n<p>Tadashi Watabe, Kosuke Mukai, Sadahiro Naka, Hisashi Sasaki, Takahiro Kamiya, Tomohiro Hayakawa, Akira Fukuhara, Takeshi Takano, Yuri Shirakami, Kenji Ooe, Sachiko Shigeno, Shota Okamura, Keisuke Masumura, Eiichi Hida, Hideki Haba, Akira Toyoshima, Kenji Isohashi, Iichiro Shimomura, Naoki Tomiyama<\/p>\n<p><strong>Institutional Affiliations:<\/strong> University of Osaka Hospital, RIKEN Nishina Center for Accelerator-Based Science, Research Center for Nuclear Physics (RCNP), University of Osaka, Japan<\/p>\n<p><strong>Trial Registration:<\/strong> NCT05275946 (Alpha-T1 Trial, 11 patients, February 2022 \u2013 May 2024)<\/p>\n<p><strong>Funding:<\/strong> AMED Clinical Research and Trial Promotion Research Project (grant 23lk0201139h0003) and Alpha-Fusion, Inc.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Watabe, T.; Mukai, K.; Naka, S.; Sasaki, H.; Kamiya, T.; Hayakawa, T.; Fukuhara, A.; Takano, T.; Shirakami, Y.; Ooe, K.; Shigeno, S.; Okamura, S.; Masumura, K.; Hida, E.; Haba, H.; Toyoshima, A.; Isohashi, K.; Shimomura, I.; Tomiyama, N. First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial). Journal of Nuclear Medicine 2025. &#8211; DOI: 10.2967\/jnumed.125.270810<\/p>\n","protected":false},"featured_media":0,"template":"","meta":[],"science_category":[49],"class_list":["post-1293","science","type-science","status-publish","hentry","science_category-at-211-publications"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial) - Atonco<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/atonco-pharma.com\/en\/science\/first-in-human-study-of-211atnaat-as-targeted-%ce%b1-therapy-in-patients-with-radioiodine-refractory-thyroid-cancer-alpha-t1-trial\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial) - Atonco\" \/>\n<meta property=\"og:description\" content=\"Watabe, T.; Mukai, K.; Naka, S.; Sasaki, H.; Kamiya, T.; Hayakawa, T.; Fukuhara, A.; Takano, T.; Shirakami, Y.; Ooe, K.; Shigeno, S.; Okamura, S.; Masumura, K.; Hida, E.; Haba, H.; Toyoshima, A.; Isohashi, K.; Shimomura, I.; Tomiyama, N. First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial). 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First-in-Human Study of [211At]NaAt as Targeted \u03b1-Therapy in Patients with Radioiodine-Refractory Thyroid Cancer (Alpha-T1 Trial). 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