Patents involving monoamine oxidase (MAO): a comprehensive update (2022–2025) on its inhibitors and applications

INTRODUCTION: Monoamine oxidases (MAOs) A and B are key enzymes for the oxidative deamination of monoamine neurotransmitters, including dopamine, serotonin, norepinephrine, and tyramine. Selective MAO-B inhibitors are clinically employed as adjuvant therapies for neurodegenerative disorders, whereas selective MAO-A inhibitors are mainly considered third-line options in the treatment of depression. However, due to their function in regulating synaptic activity and exogenous monoamine metabolism, research in this field is continually expanding. AREAS COVERED: This review summarizes patents on MAO inhibitors between 2022 and 2025. For the most investigated chemotypes (14 synthetic cores along with compounds from natural sources), biological activities were analyzed. The compounds are divided into two main categories, naturally occurring molecules and newly synthesized derivatives, with a total of 114 compounds discussed. To provide a more comprehensive perspective on the therapeutic potential of these inhibitors, additional treatment alternatives are also outlined. EXPERT OPINION: Recently patented MAO inhibitors show notable properties, including significant isoform selectivity and therapeutic potential toward other diseases, such as fibromyalgia, CDKL5-deficient disorder, neuropathic pain, and Alzheimer's disease.