In vitro assessment of the potential for abuse via the intravenous route of oxycodone DETERx® microspheres

OBJECTIVE: Abuse of prescription analgesics is a well-recognized problem, with nearly 2 million people aged 12 years or older initiating nonmedical use of pain relievers in 2012. The prevalence of opioid abuse via intravenous (IV) injection has led to the development of dosage forms designed to deter abuse using different inactive ingredients and formulation strategies. This study evaluated the IV abuse potential for a novel, microsphere-encapsulated abuse-deterrent formulation of oxycodone, Xtampza™ ER (referred to as "oxycodone DETERx"). METHODS: The extraction of oxycodone DETERx and two comparators, extended-release oxycodone (oxycodone ER) and immediate-release oxycodone (oxycodone IR), was evaluated in small volumes (5 and 10 mL) of water after manipulation of the dosage forms. The syringeability and injectability of these products were evaluated to determine the feasibility of using these products via IV injection. RESULTS: The extraction of oxycodone from oxycodone DETERx was nominal, with <12 percent extracted under any test condition. Oxycodone ER and oxycodone IR had as much as 83 and 98 percent oxycodone extracted, respectively. Injectability and syringeability analyses showed that injection of oxycodone DETERx microspheres in suspension is not feasible. In contrast, oxycodone ER and oxycodone IR suspensions were more easily drawn into and expelled from a syringe. Furthermore, injection of molten oxycodone DETERx microspheres was also shown to be ineffective. CONCLUSION: The chemical and physical properties of oxycodone DETERx provide barriers to manipulating the microspheres for the purpose of IV injection.