n-methyl-lansoprazole

N-methyl-lansoprazole (NML) is a small molecule radiopharmaceutical developed as a positron emission tomography (PET) imaging agent for the quantification of tau neurofibrillary tangles in neurodegenerative diseases. Derived from the proton pump inhibitor lansoprazole via N-methylation of the benzimidazole moiety, NML was designed to bind with high affinity to aggregated tau protein, a key pathological marker in Alzheimer's disease and other tauopathies such as progressive supranuclear palsy (PSP). The compound has been radiolabeled with both carbon-11 and fluorine-18 for clinical evaluation. Although NML demonstrated high binding affinity in vitro and favorable brain uptake kinetics in non-human primates, first-in-human studies conducted by researchers at the University of Michigan revealed low brain retention and a lack of specific in vivo signal in patients with mild cognitive impairment or Alzheimer's disease. Consequently, further development of the tracer was deemed unwarranted.

Other names

N-methyl-lansoprazole[11C]N-methyl-lansoprazole[18F]N-methyl-lansoprazole