The FDA rejected ITM Isotope Technologies Munich’s radiopharmaceutical candidate intended for neuroendocrine tumors, citing manufacturing problems that delayed a potential challenger to Novartis’ Lutathera. The agency’s action pauses the path to clinical and commercial positioning for ITM-11. ITM said the FDA identified manufacturing issues as the basis for the rejection, pushing back timelines for the therapy’s evaluation despite prior clinical reporting that compared survival outcomes against everolimus. The rejection underscores how operational scale-up and quality systems can become gatekeepers for radiopharma competition. With radiopharmaceuticals expanding as a modality, the decision also highlights the sector’s vulnerability: tightly coupled supply-chain processes, specialized manufacturing, and regulator expectations can move faster than clinical momentum. For sponsors, manufacturing readiness is now a central determinant of whether promising tumor-targeting payloads reach patients.