ZYN-001, also known as ÃÂ<sup>9</sup>-tetrahydrocannabinol <small>D</small>-glyceric acid ester, is a cannabinoid which was under development for the treatment of cancer pain, neuropathic pain, fibromyalgia, and Tourette's syndrome but was never marketed. It was formulated as a transdermal patch. The drug is a synthetic prodrug of ÃÂ<sup>9</sup>-tetrahydrocannabinol (ÃÂ<sup>9</sup>-THC) and acts as a cannabinoid CB<sub>1</sub> and CB<sub>2</sub> receptor agonist. ZYN-001 was under development by Zynerba Pharmaceuticals. It reached phase 1 clinical trials prior to the discontinuation of its development in 2018. The drug was discontinued after it failed to attain target THC blood levels of 5 to 15ng/mL in a phase 1 trial.