Efficacy and Safety Study of Transdermal Therapeutic System (TTS) Fentanyl in Participants With Osteoarthritis Knee Pain

Evaluation of Efficacy and Safety of TTS-Fentanyl in Moderate to Severe Pain From Knee Osteoarthritis

The purpose of this study is to evaluate the efficacy and safety of Transdermal therapeutic system (TTS) fentanyl patches (transdermal patch containing a drug that is put on the skin so the drug will enter the body through the skin) in knee osteoarthritis (disorder, which is seen mostly in older persons, in which the joints become painful and stiff) participants with moderate to severe pain.

This is an open-label (a medical research study in which participants and researchers are told which treatments the participants are receiving, "unblinded"), single-arm, prospective study (study following participants forward in time) of TTS-fentanyl matrix form in knee osteoarthritis participants. The study consists of 3 phases: a screening phase, an open label treatment phase consisting of 2 periods, and an evaluation phase. The first patch will be applied on the first day of treatment phase by the investigator, and sufficient patches until Day 30 will be provided to the participant with the instructions to apply the patch. The TTS-fentanyl dose will normally be increased, if needed by 12.5 microgram per hour taking into account the daily dose of supplemental paracetamol required by the participant. Efficacy with regard to pain control will be recorded principally by the participant via questionnaires in a daily diary. This record will be used to support more detailed assessments at study visits on Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire. Participants' safety will be monitored.

Inclusion Criteria:

• Chronic (lasting a long time) primary osteoarthritis knee pain, one or two side with stage II Kellgen-Lawrence, for more than 3 months with Visual Analogue Scale (VAS) more than 4
• Good knee deformity, no limit range of motion
• Participant who has signed the informed consent form

Exclusion Criteria:

• Skin disease that prevents the use of the transdermal system or which could affect the absorption of fentanyl or local tolerability
• History or suspicion of alcohol or drug abuse within the past 5 years
• History of cardiac, nervous system or respiratory disease which in the investigator's judgment prevents participation in the study because of the potential for respiratory depression
• Confusion, reduced level of consciousness, or concomitant psychiatric disorder which, in the opinion of the investigator, could prevent participation in the trial
• Participants who do not understand or speak Thai