Background: A combination of prolonged-release (PR) oxycodone with PR naloxone in one tablet (Targin PR tab®) with a fixed 2:1 ratio is available for the treatment of patients with severe pain, which can only be adequately managed with opioid analgesics. The purpose of the study was to evaluate the appropriate use of Targin PR tab® in cancer-related pain management.
Methods: The retrospective study was conducted using hospitalized cancer patients who were prescribed the Targin PR tab® (5/2.5 mg, 10/5 mg, 20/10 mg, 40/20 mg) from January 2016 to August 2016. During 8 months, the total number of hospitalized cancer patients taking Targin PR tab® was 191. According to standards of exception, 105 patients were excluded. Thus, 86 patients was reviewed using self-developed Drug Use Evaluation (DUE) criteria which was modified DUE criteria provided by Rational Pharmaceutical Management Plus (RPM plus) and World Health Organization (WHO).
Results: There were 86 patients consisting of 47 (54.7%) male patients and 39 (45.3%) female patients. Average age of the patients was 65±11 and there were 47 (54.7%) patients who were 65 years of age or older.
The results of DUE are as follows. The justification of use was 70 cases (81.4%). The adequacy of initial dose and usage was 54 cases (62.8%) and 79 cases (91.9%), respectively. Targin PR tab® was prescribed to 32 patients (37.2%) who were contraindicated in the use of this drug. Drug-related adverse effects were reported in 24 cases (27.9%). Most of the side effects were gastrointestinal events, such as constipation. In 72 cases (83.7%), Targin PR tab® was prescribed with other drugs, potentially changing its PK/PD profile. The compliance rates of initial pain evaluation during hospitalization were 85 cases (98.8%). However, the appropriate control of breakthrough pain and reevaluation of pain showed 64 cases (74.4%). In 52 cases (60.5%), the dose or type of drug is effectively modified according to pain control guidelines in cancer patients.
Conclusion: The justification of use indicated the medication was highly suitable. However, according to regular pain evaluation, the modification of dose and formulation were slightly inadequate. These results suggest the need to upgrade the management of cancer-related-pain to help cancer patients improve their quality of life.