Dr. McCurdy serves as Associate Dean for Faculty Development and Professor in the Departments of Medicinal Chemistry and Pharmaceutics; and The Frank A. Duckworth Eminent Scholar Chair in Drug Research and Development at the University of Florida College of Pharmacy. He is also the Director of the UF Translational Drug Development Core. Dr. McCurdy completed his training as a pharmacist at Ohio Northern University and his PhD in medicinal chemistry from the University of Georgia, followed by a three-year postdoctoral fellowship at the University of Minnesota under Prof. Philip Portoghese. McCurdy began his academic career in 2001 at the University of Mississippi where he rose to the rank of full professor (with tenure). He moved to the University of Florida in January of 2017. His research focuses on the design, synthesis, and development of drugs to treat pain, anxiety, mental health and substance use disorders. He is an internationally recognized expert on kratom (Mitragyna speciosa). He also has developed a PET/MR imaging diagnostic agent for visualizing the origins of chronic neuropathic pain. Phase 1 and 2 human clinical trials are currently underway. He has published more than 220 manuscripts and holds 8 patents. During his career he has been and continues to be funded by multiple grants from many sources, including NIDA, totaling over $40M. Dr. McCurdy serves as a consultant to the US Food and Drug Administration’s Drug Safety and Risk Management Advisory Committee and previously served as President of the American Association of Pharmaceutical Scientists (AAPS). He has trained over 25 PhD students, numerous postdoctoral fellows and scientists, and well over 100 undergraduate students from around the globe.
Title - Kratom: How Pharmaceutical Sciences Advanced Understanding and Regulation
Abstract
Mitragyna speciosa Korth (Rubiaceae) is a tree that was first identified in Southeast Asia where the borders of Thailand and Malaysia meet. The leaves are the origin of the ethnopharmacological preparation “kratom”. Traditional use involves decoction of the leaves and has paradoxical effects that include a coca-like stimulant as well opium-like depressant actions. Traditionally, the plant extract has been used as an opium substitute, and it has been clinically used in Thailand to wean addicts off opiates. Much attention has been drawn to this recently due to the exponential increases of users in the Western world where some harm has been reported. For centuries kratom has been used to increase mood, stamina, energy, and decrease anxiety and pain. The historical use of kratom to prevent withdrawal and ween users from opioids is of great relevance to the current global opioid crisis. As kratom use has steadily increased in the United States (US), reports of adverse events have risen. It is estimated that >15 million US individuals consume kratom products. Poison control center calls mentioning kratom have risen by about 1,200% over the last decade with a highly significant surge in the last year. This number of kratom incidents is small when put in context with other analgesics, sedatives, and antidepressants which resulted in 334,729 calls in 2019. Nonetheless, there has been increased scrutiny around the opioid nature of kratom. From our conducted studies, supported by two (2) large grants from the National Institute on Drug Abuse (totaling $11,535,437), we conclude that kratom has low abuse liability when it is utilized in its pure leaf/plant material form. We believe issues arise from concentrated extracts and other formulations that utilize dried or cured leaf materials. The abuse liability in these products is most likely due to the varying concentrations of one alkaloid, 7-hydroxymitragynine (7OHMG). We have not detected this alkaloid in freshly harvested leaf material or freshly prepared traditional teas in SE Asia. As part of our research, we monitor products in the US marketplace and over the past decade, the presence of 7OHMG has been decreasing to low or non-detectable levels in many products. 7OHMG is a potent mu opioid receptor agonist with abuse potential. It is a metabolite or decomposition product of the major alkaloid, mitragynine (MG). We, and others, have shown that MG has no abuse potential and has a unique pharmacology involving several neurotransmitter systems. In fact, alkaloids in kratom interact with the adrenergic and serotonergic systems to a greater extent than opioid systems. This polypharmacology renders kratom unique from other opioids and to label kratom an opioid is scientifically and factually incorrect. MG and lyophilized kratom tea can reduce opioid withdrawal symptoms in opioid dependent subjects. Two reports in the literature demonstrate the ability of MG to block self-administration of opioids in animals. In 2016, the US determined further research was needed before a ban. That research has exponentially increased to the point of FDA sanctioned human clinical trials. In October 2021, the 44th Expert Committee (ECDD) on Drug Dependency of the World Health Organization convened to determine if kratom should undergo ‘critical review’ for an International ban. The ECDD determined that there was inadequate evidence to recommend a critical review and kratom will be kept under surveillance. In late 2023, synthetically derived kratom alkaloids entered commerce, with 7OHMG being the first. In July 2025, the FDA encouraged the DEA to schedule 7OHMG and to date this has not occurred.