Cancer Pain Management With Hydromorphone HCl ORal Osmotic System in Korean Cancer Patient: Evaluation of Its Clinical Usefulness in Reduction of Breakthrough Pain Medication Frequency

This is an open-label (all people know the identity of the intervention), multi-center (conducted in more than 1 center), prospective (study following participants forward in time) study. The total duration of study will be 3 weeks. The study consists of 2 periods and 4 visits: screening period (1 week; Visit 1) and treatment period (2 weeks; Visit 2, 3 and 4). During screening period at Visit 1, potential participants will receive previously administered oral opioid analgesic until the second visit and with immediate-release opioid analgesic whenever breakthrough pain is present. During treatment period, from second visit to the fourth visit, participants will receive the hydromorphone HCl OROS once daily for 2 weeks. At Investigator's discretion, participants completing 2 weeks of treatment with study drug could be enrolled into the extension phase of 12-weeks. The dose of study drug is flexible and will be increased or decreased based on the frequency of immediate-release opioid analgesic doses needed to manage pain. At second visit, initial dose of hydromorphone will be determined according to the equivalent analgesic effect conversion tablet (oxycodone 10 milligram [mg] twice daily is equal to hydromorphone HCl 8 mg once daily). The Investigator will increase a participant's daily dose if more than 3 breakthrough pain episodes require rescue medication within a 24 hours period. Participants' safety will be monitored throughout the study.