Cochrane: Pain in bones, joints and muscles is very common and can often be persistent. It is expected that 50% of the general population will suffer from this type of pain for at least three months or longer during their lifetime. This condition is called chronic musculoskeletal pain. Opioids are a type of strong pain-killer drug that are used to treat people that have moderate-to-severe chronic pain. People taking these drugs frequently have adverse events (side effects), including severe adverse events. This Cochrane review aimed to assess the efficacy (reduction in pain intensity) and safety of tapentadol (a new opioid) in moderate-to-severe chronic musculoskeletal pain, in comparison to placebo and other active drugs.


There is moderate quality evidence that three out of 10 patients treated with tapentadol had at least 50% pain reduction (responded to the treatment) while only two out of 10 oxycodone and placebo-treated patients responded to the treatment.
There is also moderate quality evidence that tapentadol-treated patients were at a higher risk of withdrawal from the trial due to adverse events in comparison to placebo (two out of 10 tapentadol-treated patients and one out of 10 placebo-treated patients withdrawn due to adverse events). For oxycodone-treated patients, four out of 10 withdrew due to adverse events. Constipation, nausea and vomiting, and itching (pruritus) events were less with tapentadol than with oxycodone but without any difference in fatigue, insomnia, sleepiness (somnolence) and headache.
The overall clinical benefit of tapentadol in moderate-to-severe chronic musculoskeletal pain found in randomised clinical trials is relatively small (a common conclusion found in all opioids trials for chronic pain). Further studies are needed to ascertain which patients with chronic musculoskeletal pain would benefit the most from this new opioid.

Authors' conclusions: 

Tapentadol extended release is associated with a reduction in pain intensity in comparison to placebo and oxycodone. However, the clinical significance of the results is uncertain due to the following reasons: modest difference between interventions in efficacy outcomes, high heterogeneity in some comparisons and outcomes, high withdrawals rates, lack of data for the primary outcome in some studies and impossibility to use BOCF as imputation method. Tapentadol is associated with a more favourable safety profile and tolerability than oxycodone.