Integrated strategy for use of positron emission tomography in nonhuman primates to confirm multitarget occupancy of novel psychotropic drugs: An example with AZD3676
2016 (English)In: Journal of Pharmacology and Experimental Therapeutics, ISSN 0022-3565, E-ISSN 1521-0103, Vol. 358, no 3, 464-471 p.Article in journal (Refereed) Published
Positron emission tomography (PET) is widely applied in central nervous system (CNS) drug development for assessment of target engagement in vivo. As the majority of PET investigations have addressed drug interaction at a single binding site, findings of multitarget engagement have been less frequently reported and have often been inconsistent with results obtained in vitro. AZD3676 [N,N-dimethyl-7-(4-(2-(pyridin-2-yl)ethyl)piperazin-1-yl) benzofuran-2-carboxamide] is a novel combined serotonin (5- hydroxytryptamine) 5-HT1A and 5-HT1B receptor antagonist that was developed for the treatment of cognitive impairment in Alzheimer's disease. Here, we evaluated the properties of AZD3676 as a CNS drug by combining in vitro and ex vivo radioligand binding techniques, behavioral pharmacology in rodents, and PET imaging in nonhuman primates. Target engagement in the nonhuman primate brain was assessed in PET studies by determination of drug-induced occupancy using receptorselective radioligands. AZD3676 showed preclinical properties consistent with CNS drug potential, including nanomolar receptor affinity and efficacy in rodent models of learning and memory. In PET studies of the monkey brain, AZD3676 inhibited radioligand binding in a dose-dependent manner with similar affinity at both receptors. The equally high affinity at 5-HT1A and 5-HT1B receptors as determined in vivo was not predicted from corresponding estimates obtained in vitro, suggestingmore than 10-fold selectivity for 5-HT1A versus 5-HT1B receptors. These findings support the further integrated use of PET for confirmation of multitarget occupancy of CNS drugs. Importantly, earlier introduction of PET studies in nonhuman primates may reduce future development costs and the requirement for animal experiments in preclinical CNS drug development programs.
Place, publisher, year, edition, pages
American Society for Pharmacology and Experimental Therapy , 2016. Vol. 358, no 3, 464-471 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:kth:diva-194901DOI: 10.1124/jpet.116.234146ISI: 000389065700011PubMedID: 27402278ScopusID: 2-s2.0-84983801352OAI: oai:DiVA.org:kth-194901DiVA: diva2:1052899
FunderScience for Life Laboratory - a national resource center for high-throughput molecular bioscience
QC 201612072016-12-072016-11-012017-01-03Bibliographically approved