Dosimetry Results from the Phase 1b/3 ACTION-1 Trial of [225Ac]Ac-DOTATATE (RYZ101) in Patients with Somatostatin Receptor-Expressing, Well-Differentiated GEP-NETs
Alpha-particle radiation therapy for neuroendocrine tumors shows favorable dosimetry with acceptable kidney safety, supporting clinical testing in patients resistant to other treatments.
This dosimetry substudy from the pivotal ACTION-1 phase 1b/3 trial demonstrates feasibility of SPECT/CT-based dosimetry for alpha-emitting [225Ac]Ac-DOTATATE in GEP-NETs, with favorable tumor-to-normal tissue ratios and acceptable kidney doses. As part of a randomized phase 3 trial, this supports the rational dosing framework for a potentially practice-changing alpha-theranostic agent in 177Lu-refractory NET patients.
What the study was
- Study design
- Phase 1b/3 randomized trial dosimetry substudy (ACTION-1, NCT05477576)
- Population
- Adults with grade 1/2 well-differentiated SSTR2-expressing GEP-NETs progressed after 177Lu-SSA therapy
- Sample size
- 9
- Category
- Treatment Innovation
- Maturity
- Exploratory
- Journal
- J Nucl Med
Why it surfaced
Part of active phase 3 trial (ACTION-1); alpha-emitting DOTATATE represents next-generation theranostic after lutetium-DOTATATE approval. Dosimetry substudy (n=9) is preliminary but enables rational clinical trial dosing.
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