BOSTON, Mass. — September 27, 2026
ITM Isotope Technologies Munich SE and Lumara Bio announced new real-world re-treatment and dosimetry data for investigational non-carrier-added ¹⁷⁷Lu-edotreotide (ITM-11) in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). The findings were presented in two posters at the 2026 American Society for Radiation Oncology (ASTRO) Annual Meeting in Boston. An investigator-led retrospective analysis from the SwissNET registry evaluated outcomes following re-treatment with ¹⁷⁷Lu-edotreotide, while a dosimetry substudy from the Phase 3 COMPETE trial assessed radiation exposure in tumors and healthy organs.
SwissNET Analysis Reports Longer Survival After Re-treatment
The SwissNET registry analysis included 49 adults with metastatic, well-differentiated, somatostatin receptor-positive NETs who experienced disease progression at least 12 months after completing initial ¹⁷⁷Lu-edotreotide treatment. Thirty-seven patients were re-treated with ¹⁷⁷Lu-edotreotide, while 12 received non-radiopharmaceutical systemic anticancer therapy. Patients re-treated with ¹⁷⁷Lu-edotreotide had a median real-world progression-free survival of 12.5 months compared with 4.8 months for the non-radiopharmaceutical systemic therapy group (p<0.001). Median overall survival was 90.1 months versus 39.8 months, respectively (p<0.001). Because the analysis was retrospective and non-randomized, these findings represent real-world associations and do not establish that re-treatment with ¹⁷⁷Lu-edotreotide caused the observed survival differences.
COMPETE Dosimetry Shows Favorable Tumor-to-Kidney Exposure
The Phase 3 COMPETE dosimetry substudy evaluated absorbed radiation doses in healthy organs among 17 patients and in 17 tumor lesions from nine patients. The analysis found that tumor absorbed dose was significantly higher than absorbed dose to normal organs. Kidney absorbed dose coefficients remained relatively constant with low intra-patient variability, with a median variability of 14%, supporting further evaluation of whether early-cycle dosimetry could help inform individualized treatment strategies. Tumor absorbed dose coefficients decreased over time, consistent with observations in radiopharmaceutical therapy, while tumor-to-kidney absorbed dose ratios remained above 1 across treatment cycles, indicating higher radiation delivery to tumors than to kidneys in the analyzed patients.
Advertisement
ITM Advances 177Lu-Edotreotide in GEP-NET Development
The new data add to the clinical development program for ¹⁷⁷Lu-edotreotide, a proprietary synthetic targeted radiotherapeutic being evaluated in GEP-NETs. The Phase 3 COMPETE trial (NCT03049189) compared ¹⁷⁷Lu-edotreotide with everolimus in patients with inoperable, progressive Grade 1 or Grade 2 GEP-NETs and met its primary endpoint of progression-free survival. The investigational radiotherapeutic is also being evaluated in the Phase 3 COMPOSE study in patients with well-differentiated, aggressive Grade 2 or Grade 3, SSTR-positive GEP-NETs. ¹⁷⁷Lu-edotreotide is not approved by any regulatory authority, and its safety and efficacy for any intended use have not been established. The SwissNET and dosimetry findings provide additional clinical and treatment-planning information as ITM continues evaluating the radiopharmaceutical across its development programs.
Source :ITM Isotope Technologies press release
