An iterative model for in vitro laboratory assessment of tamper deterrent formulations.

BACKGROUND In an effort to address the continuing problem of prescription opioid abuse, manufacturers are incorporating new technologies into formulations that are designed to deter product tampering and misuse. Standards for laboratory assessment of tamper deterrent properties of new formulations have not previously been developed. METHODS Experimental designs were developed for the in vitro laboratory assessment of the tamper deterrent properties of reformulated oxycodone. Given that an exhaustive study of all potential tampering methods was impractical; this model was developed to evaluate the product in an incremental fashion with iterative changes that were amenable to objective and replicable laboratory testing. RESULTS A description of the model is provided along with pertinent examples involving assessment of reformulated oxycodone with comparisons to the original formulation. Physical and chemical procedures were developed that relate to "real-world" scenarios that may be applied to opioid formulations. Test results were interpreted in relation to the relative ease or difficulty of the manipulation as compared to control materials and the amount and purity of active drug that could be accessed. Results from some of the tests were designed to be useful in predicting whether specific tampering methods would facilitate or deter drug administration by different routes of administration. CONCLUSIONS This model, developed to assess the tamper deterrent properties of reformulated oxycodone, should have application in the assessment of other drug formulations designed to exhibit tamper deterrence properties.