Bayer announced receipt of US FDA approval for Ambelvist (gadoquatrane), a macrocyclic gadolinium-based contrast agent (mGBCA) for contrast-enhanced MRI in adults and pediatric patients, including term neonates. The agent is indicated to detect and visualize lesions with abnormal vascularity across both the central nervous system and non-CNS body regions, and carries the distinction of being the lowest-dose mGBCA approved in the US.
Ambelvist is administered intravenously at a recommended dose of 0.01 mmol/kg body weight, delivering 0.04 mmol of gadolinium per kilogram — 60% less gadolinium than standard mGBCAs dosed at 0.1 mmol Gd/kg, and 20% less than Bracco Diagnostics’ gadopiclenol (Vueway), which delivers 0.05 mmol Gd/kg. The reduced dose is enabled by a novel tetrameric molecular structure that confers high relaxivity, meaning greater signal enhancement per gadolinium atom. This allows diagnostic image quality to be maintained at a substantially lower gadolinium burden, a consideration that has grown in clinical relevance given guidance from bodies such as the American College of Radiology to use the lowest gadolinium dose necessary for adequate imaging.
The approval is supported by the Phase III QUANTI clinical program, which evaluated gadoquatrane in adult and pediatric patients undergoing contrast-enhanced MRI. The studies demonstrated that combined pre- and post-contrast MRI sets with gadoquatrane improved lesion visualization compared with pre-contrast imaging alone. In descriptive analyses, visualization scores and lesion counts for gadoquatrane at 0.04 mmol Gd/kg were reported to be similar to those for comparator mGBCAs dosed at 0.1 mmol Gd/kg. Pediatric data included 93 patients aged 28 days to under 18 years, supporting labeling across the full age range down to term neonates.