Clinical Usefulness of Hydromorphone-OROS in Improving Sleep Disturbances in Korean Cancer Patients: A Multicenter, Prospective, Open-Label Study

PURPOSE To evaluate the efficacy of hydromorphone-OROS (HM-OROS) in reducing sleep disturbance and relieving cancer pain. MATERIALS AND METHODS One hundred twenty cancer patients with pain (numeric rating scale [NRS] ≥ 4) and sleep disturbance (NRS ≥ 4) were evaluated. The initial HM-OROS dosing was based on previous opioid dose (HM-OROS:oral morphine=1:5). Dose adjustment of the study drug was permitted at the investigator's discretion. Pain intensity, number of breakthrough pain episodes, and quality of sleep were evaluated. RESULTS A total of 120 patients received at least one dose of HM-OROS; 74 of them completed the final assessment. Compared to the previous opioids, HM-OROS reduced the average pain NRS from 5.3 to 4.1 (p < 0.01), worst pain NRS from 6.7 to 5.4 (p < 0.01), sleep disturbance NRS from 5.9 to 4.1 (p < 0.01), incidence of breakthrough pain at night from 2.63 to 1.53 times (p < 0.001), and immediate-release opioids use for the management of breakthrough pain from 0.83 to 0.39 times per night (p = 0.001). Of the 74 patients who completed the treatment, 83.7% indicated that they preferred HM-OROS to the previous medication. The adverse events (AEs) were somnolence, asthenia, constipation, dizziness, and nausea. CONCLUSION HM-OROS was efficacious in reducing cancer pain and associated sleep disturbances. The AEs were manageable.