US FDA declines Lantheus' tumor imaging kit over third-party manufacturing issues

The U.S. Food and Drug Administration declined to approve Lantheus Holdings' diagnostic imaging kit for types of cancer tumors, citing unresolved issues at a third-party manufacturing facility, the company said on Friday.

This marks another setback for Lantheus, as the health regulator had in March extended its review of the imaging kit, LNTH-2501, by three months.

The FDA did not identify any concerns regarding the data submitted by Lantheus or the safety and efficacy of LNTH-2501, the company said.

"The feedback received from the FDA relates solely to our third-party manufacturer, and not to the clinical performance of the product," said CEO Mary Anne Heino.

The company is working with the manufacturer and the regulator to address the concerns, Heino said.

LNTH-2501 is a diagnostic radiopharmaceutical kit used with PET scans to detect neuroendocrine tumors, or NETs - cancers that arise in hormone-producing cells in organs such as the lungs, pancreas and digestive tract.

The condition is more common in adults than children, and the slow-growing subtype once known as carcinoid tumor affects ​about four in ​every 100,000 adults, according to the National ​Institutes of Health.

(Reporting by Sahil Pandey and Puyaan Singh in Bengaluru; Editing by Sahal Muhammed)

Copyright Reuters or USA Today Network via Reuters Connect

This story was originally published June 26, 2026 at 4:43 PM.