WASHINGTON D.C (VINnews) — The U.S. Food and Drug Administration on Thursday approved Tauklarify, a brain PET imaging agent designed to help evaluate adults with cognitive impairment for Alzheimer’s disease.

Tauklarify, known chemically as florquinitau F 18 injection and previously studied as MK-6240, detects tau neurofibrillary tangle pathology in the brain. The information it provides is intended to complement amyloid PET scans and other diagnostic tools.

Lantheus Holdings manufactures the agent. Enigma Biomedical USA developed it earlier and sold the related subsidiary to Lantheus in 2023; the companies continued collaborating through approval.

The FDA based its decision on two blinded-read studies drawn from three clinical trials involving more than 500 participants. Independent readers who were unaware of patients’ clinical histories or amyloid PET results interpreted the scans. Safety data came from 1,734 subjects.

Side effects were uncommon. Headache occurred in 0.7% of subjects, nausea in 0.2%, and injection-site reactions, dizziness and abdominal discomfort each in 0.1%.

Tauklarify is the second FDA-approved fluorine-18 tau imaging agent, following Tauvid (flortaucipir). A multicenter trial known as the HEAD study, published in The Lancet in May, directly compared the two agents in roughly 775 patients across eight North American sites.

The approval includes an important limitation: safety and effectiveness have not been established for evaluating tauopathies unrelated to Alzheimer’s disease.

Researchers and clinicians said the tool may help track disease progression, especially in patients with early or mild cognitive symptoms.