Pregabalin for the treatment of fibromyalgia

Fibromyalgia (FM) is the most common cause of chronic widespread body pain in humans. Co-morbidities include sleep disturbance, fatigue, impaired physical functioning, altered mood and negative effects on health-related quality of life. Pregabalin inhibits presynaptic release of pronociceptive neurotransmitters in the CNS; this likely underpins its therapeutic benefit in patients with FM.

This review addresses pregabalin pharmacokinetics, efficacy and adverse event (AE) profiles from randomized controlled trials and open-label extension studies in patients with FM. These effects are compared with those of the serotonin norepinephrine reuptake inhibitors, duloxetine and milnacipran that also have FDA approval for the treatment of fibromyalgia.

At the approved dosages, oral pregabalin has at most a moderate therapeutic benefit above placebo with tolerable side-effects, in no more than 50% of patients with FM. Durability of clinically meaningful (≥ 30%) pain relief in pregabalin-responders has been demonstrated for at least 6-months, but longer-term studies are required as most patients have symptoms for decades. Exclusion of patients with common co-morbidities from the pregabalin RCTs in FM raises questions on the generalizability of the RCT findings to the typical patient seen in clinical practice and so additional investigation is required.