An Efficacy and Safety Study for Tapentadol Extended Release (JNS024ER) in Chronic Pain Participants

Inclusion Criteria: * Participants with chronic pain due to osteoarthritis of knee or low back pain continuing for at least 12 weeks before informed consent * Participants who did not achieve adequate analgesia (pain control) with routine treatment with an oral non-opioid analgesic (drug used to control pain) at its usual upper-limit dose or at an adequate fixed dose for at least 14 consecutive days during the 12 weeks before informed consent * Participants who have not experienced treatment with conventional opioids, except for short term use of opioid analgesics for treatment of post-operative acute pain more than 30 days before consent or temporary use of codeine phosphate or dihydrocodeine phosphate for purposes other than pain relief (e.g. for antitussive) more than 2 days before informed consent * Participants with average pain intensity score of greater than or equal to 5 on an 11-point Numerical Rating Scale (NRS) during 48 hours before informed consent and are considered requiring opioid treatment by the Investigator * Participants who are able to visit the medical institutions throughout the study period Exclusion Criteria: * Participants who are taking a monoamine oxidase inhibitor within 14 days before informed consent * Participants with current or a history of epilepsy or seizure disorders * Participants suspected with intracranial hypertension (e.g. traumatic encephalopathy) * Participants with uncontrolled or clinically significant arrhythmia (irregular heart rate) * Participants with moderate to severe liver dysfunction or severe renal dysfunction