The U.S. Food and Drug Administration has approved Lantheus Holdings’ radioactive imaging agent Tauklarify for brain scans used to assess patients for Alzheimer’s disease. The product is injected before a positron emission tomography, or PET, scan, allowing abnormal tau protein deposits linked to Alzheimer’s to be seen in brain images of adults with cognitive impairment being evaluated for the disease. Lantheus said a positive scan does not necessarily confirm tau pathology, while a negative scan does not rule it out. The approval was supported by two studies in which independent readers reviewed Tauklarify PET scans from more than 500 participants and classified them as positive or negative for tau pathology.