Background: In efforts to reduce misuse of opioids, new abuse deterrent formulations of medications have been developed. Insurers increasingly give abuse-deterrent opioid formulations preferred formulary status, which can result in required formulation rotation for patients. Xtampza® (oxycodone myristate extended-release) is an abuse-deterrent opioid formulation that maintains its extended-release properties with any physical manipulation. Blood levels of oxycodone myristate extended-release (OxyM-ER) may vary with dietary caloric and fat intake.
Case description: A woman with metastatic breast carcinoma had severe myalgias and arthralgias well-managed with oxycodone hydrochloride extended-release (OxyHCl-ER) and hydrocodone/acetaminophen. A switch from OxyHCl-ER to OxyM-ER resulted in worsened pain management, decreased functional status, and a referral to palliative care (PC). Recognizing calorie-depending pharmacokinetic variability with OxyM-ER, the interdisciplinary PC team obtained a detailed dietary history from the patient, which revealed a low-fat, low-calorie healthy diet with inconsistent meals. After repeated education, the patient changed her diet and had improved pain and functional status without increasing her total daily opioid dose.
Conclusion: The efficacy of OxyM-ER may be compromised in patients with cancer experiencing anorexia, decreased or inconsistent food intake, or low-fat/low-calorie diets. An interdisciplinary team approach can improve pain control in the setting of "forced" formulary switches to OxyM-ER.
Keywords: Xtampza; abuse-deterrent; bioavailability; opioid formulations; opioids; oxycodone; oxycodone extended-release; oxycodone myristate; palliative care; patient education.