ITM radiopharmaceutical dose-response data backs ITM-11 in GEP-NETs
ITM Isotope Technologies Munich and its oncology division Lumara Bio presented a cluster of radiopharmaceutical datasets at the European Association of Nuclear Medicine (EANM) 2026 Congress in Vienna, with the headline finding demonstrating a strong dose-response relationship for their lead asset, 177Lu-edotreotide (ITM-11), in gastroenteropancreatic neuroendocrine tumours (GEP-NETs).
The dose-response analysis, drawn from 106 evaluable patients in ITM's Phase 3 COMPETE trial, showed that objective response rate (ORR) climbed from 12% in the lowest cumulative tumour absorbed dose quartile to 64% in the highest quartile. Three complete responses were recorded in patients receiving a cumulative dose above 86.1 Gy. Multivariate logistic regression identified cumulative tumour absorbed dose and tumour type as the primary predictors of response, with lesion-level analysis confirming a statistically significant association.
Dr Anthime Flaus of the Hospices Civils de Lyon, who presented the analysis, said the dosimetry findings "provide important evidence that could potentially support the development of more individualised radiopharmaceutical treatment approaches, with the goal of optimising patient care and outcomes."
Early-pipeline data across three additional candidates
Beyond ITM-11, three investigator-led studies provided supporting data for early-stage pipeline assets. Ga-DPI-4452, a gallium-68-labelled PET imaging agent targeting carbonic anhydrase IX (CAIX) for clear cell renal cell carcinoma (ccRCC), demonstrated abnormal findings in 91.8% of confirmed ccRCC patients across a 98-patient retrospective registry. The agent also outperformed conventional CT across 153 predefined anatomical regions, including primary renal tumours, lymph nodes and bone metastases. Ga-DPI-4452 received FDA Fast Track Designation in October 2025, which should accelerate dialogue with regulators on a registration path.
The terbium-161-labelled SSTR2 antagonist Tb-DOTA-LM3 (ITM-63) showed a peptide mass-dependent dosimetry effect in six patients with metastatic GEP-NETs: reducing peptide mass below 100 µg versus 300-400 µg nearly doubled tumour absorbed dose (23.3 vs 12.5 Gy/GBq, p less than 0.001), with no dose-limiting toxicities observed. Meanwhile, translational data for n.c.a. 177Lu-TTM (ITM-31), an intracavitary radioimmunotherapy for glioblastoma, confirmed high carbonic anhydrase XII (CAXII) expression in the tumour infiltration zone, strengthening the biological rationale for targeting this protein after surgical resection.
Competitive and regulatory context
The radiopharmaceutical sector has attracted substantial industrial and regulatory attention following the commercial success of Novartis's lutetium-177 DOTATATE (Lutathera) in GEP-NETs and 177Lu-PSMA-617 (Pluvicto) in prostate cancer. ITM's ITM-11 uses the same radioisotope and a related somatostatin-targeting peptide, but is produced without carrier molecules, a distinction ITM argues delivers more consistent dosimetry. The COMPETE trial, which met its primary endpoint of progression-free survival against everolimus, has already demonstrated efficacy at the trial level; the EANM dose-response analysis now provides dosimetric mechanistic support for that finding and hints at a path toward personalised dosing protocols.
The broader theranostics field is consolidating around a small number of isotope platforms, with terbium-161 attracting interest as a next-generation alternative to lutetium-177 owing to its additional Auger and conversion electron emissions. If the dosimetry advantage observed in the Phase 0b BETA PLUS study for Tb-DOTA-LM3 is confirmed in larger cohorts, ITM could position the asset as a differentiated successor to lutetium-based SSTR therapies. Regulatory precedent for SSTR-targeted radiotherapy is well established in the US and Europe, reducing the pathway uncertainty for late-stage candidates in this class.
All four candidates discussed at EANM 2026 remain investigational and have not received regulatory approval.