MDMB-FUBINACA (also known as MDMB(N)-Bz-F and FUB-MDMB) is an indazole-based synthetic cannabinoid that is a potent agonist for cannabinoid receptors and that has been sold online as a designer drug. The structure of MDMB-FUBINACA contains the amino acid 3-methylvaline, also known as l-tert-leucine. MDMB-FUBINACA has K<sub>i</sub> values of 1.14nM at CB<sub>1</sub> and 0.1228nM at CB<sub>2</sub> and EC<sub>50</sub> values of 0.2668nM at CB<sub>1</sub> and 0.1411nM at CB<sub>2.</sub>
There have been a large number of reported cases of deaths and hospitalizations in relation to this synthetic cannabinoid, mainly in Russia and Belarus. MDMB-FUBINACA was first reported in 2014 and quickly gained a reputation as the most deadly synthetic cannabinoid drug sold by 2015. Up to 700 hospitalisations and 25 deaths were initially linked to MDMB-FUBINACA in media and government reports, and subsequent testing confirmed that at least 1000 hospitalisations and 40 deaths had occurred as a consequence of intoxication by MDMB-FUBINACA as of March 2015.
In the United States, MDMB-FUBINACA is a Schedule I controlled substance.
As of October 2015, MDMB-FUBINACA is a controlled substance in Belarus, Russia, and China.
In July 2021, it was included in Table II-A in the list of prohibited drugs of Portugal.