Review of pharmacological therapies in fibromyalgia syndrome

Abstract

This review addresses the current status of drug therapy for the management of fibromyalgia syndrome (FMS) and is based on interdisciplinary FMS management guidelines, meta-analyses of drug trial data, and observational studies. In the absence of a single gold-standard medication, patients are treated with a variety of drugs from different categories, often with limited evidence. Drug therapy is not mandatory for the management of FMS. Pregabalin, duloxetine, milnacipran, and amitriptyline are the current first-line prescribed agents but have had a mostly modest effect. With only a minority of patients expected to experience substantial benefit, most will discontinue therapy because of either a lack of efficacy or tolerability problems. Many drug treatments have undergone limited study and have had negative results. It is unlikely that these failed pilot trials will undergo future study. However, medications, though imperfect, will continue to be a component of treatment strategy for these patients. Both the potential for medication therapy to relieve symptoms and the potential to cause harm should be carefully considered in their administration.

Clinical Trials for Patients with Fibromyalgia Syndrome

“…A number of drugs are currently in development for FM relecting the interest by the pharmaceutical industry into this condition [9,10]. For the majority of drugs that have been or are currently in clinical trials for FM, however, this condition (and thereby the patient population) is secondary to that for which the compound has been initially developed or approved.…”

“…he lack of understanding of the pathophysiology of FM has prevented the availability of clues for the rational design of mechanistically based drug treatment approaches. As a consequence, attempts to identify new therapies involve either the assessment of existing therapeutic strategies with the potential of improving tolerability, or evaluation of drugs that have previously demonstrated eicacy in another condition for a symptom associated with FM [1,9]. he successes of many of the clinical trials have been limited by the complexities of FM.…”

“…Pain management has oten been a single or the primary symptom endpoint of trials in FM with limited consideration of other symptoms [1,8,9], however a more frequent involvement of quality of life assessment is being recognised. Although the clinician-investigators' identiied core domains as most important for assessment in FM studies has oten been primarily focused on reducing pain, an OMERACT (Outcome Measures in Rheumatology) Delphi exercise identiied several other important patient-reported concerns (e.g.…”

“…he efectiveness of the diferent approaches is oten short-lived and large variations in treatment response have been cited [8,9]. Many drugs with pharmacologically diferent mechanisms have demonstrated efectiveness in subgroups of FM patients, but no single drug has addressed the complete range of FM symptoms nor met the needs of all patients consistent with a heterogeneity of the patient population [9,10]. Drug treatment remains largely empiric with the condition being managed through targeting individual symptoms where results are highly variable and long-term prospective observational studies have found that outcomes are typically poor.…”

“…he chronic nature of FM and large intrinsic variability of symptoms, particularly pain, over short periods of time requires pharmacological therapies with long-term eicacy which may not be observed across all symptoms within the irst few weeks of treatment, consequently short-term trials (eg up to 12 weeks) will not provide clinically applicable outcomes [1,[9][10][11]. Although evidence from clinical studies indicates that certain pharmacological agents, eg pregabalin and duloxetine, can provide meaningful beneit in FM within one to two weeks with early improvement being a predictor of treatment outcome, proof of adequate long-term eicacy requires attention [12].…”