An Efficacy and Safety Study of Fentanyl in Participants With Chronic Pain

Inclusion Criteria: * Participants whose medication for chronic pain meets one of the criteria among a to e (2 or more types of opioid analgesics must not be used): a) Participants who are taking non-opioid analgesic at the normal highest dose or more for at least 14 consecutive days during 12 weeks before the informed consent, but were not continuously taking the non-opioid analgesic during 14 days before the informed consent for medical reasons such as safety b) Participants who are continuously taking an additional analgesic with a certain dosage and administration for at least 14 consecutive days before the informed consent c)Participants who are continuously taking codeine phosphate or dihydrocodeine phosphate less than 270 milligram (mg) daily (except for rescue treatment) for at least 14 consecutive days before the informed consent d) Participants who are continuously taking codeine morphine hydrochloride of oral morphine equivalent dose of less than 45 mg daily (except for rescue treatment) for at least 14 consecutive days before the informed consent (less than 30 mg daily for suppositories and less than 15 mg daily for injections) e) Participants who are continuously taking fentanyl citrate injection of less than 0.3 mg daily (except for rescue treatment) for at least 14 consecutive days before the informed consent * Participants with chronic pain continuing for at least 12 weeks before informed consent * Participants with an average pain intensity of greater than or equal to 50 millimeter (mm) on the Visual Analog Scale in 24-hour daily living before informed consent * Participants who can be hospitalized to the 4th day after the initiation of patch application * Participants who were given a sufficient explanation about the investigational product and the study and gave their own consent to participate in the study Exclusion Criteria: * Participants whose main cause of the pain to be assessed is considered attributable to psychogenic pain * Participants with severe respiratory function disorders * Participants with asthma (breathing disorder in which there is wheezing and difficulty breathing) and bradyarrhythmia (slow, irregular heartbeats) * Participants with hepatic dysfunction function such as fulminant hepatitis (inflammation of the liver) and liver cirrhosis (serious liver disorder in which connective tissue replaces normal liver tissue, and liver failure often occurs), or renal impairment such as nephritic syndrome, acute renal failure, a…