Mardepodect (PF-2545920) is a potent and selective phosphodiesterase 10A (PDE10A) inhibitor primarily investigated for therapeutic applications in neuroscience, particularly psychiatric disorders like schizophrenia. It regulates intracellular signaling in the brain by elevating cAMP and cGMP levels, enhancing neurotransmission and neuronal function. This addresses dysregulated dopamine and glutamate signaling. Preclinical studies demonstrated efficacy in cognitive and behavioral symptoms. Its potential for neuropsychiatric conditions like Huntington's and Parkinson's disease was explored due to neuroprotective effects on striatal pathways.

Development was discontinued by Pfizer in 2013 after Phase II clinical trials failed to meet efficacy endpoints for schizophrenia. It is available as a research chemical (not for human use) and a valuable tool for studying PDE10A pathways.