Safety and efficacy of esreboxetine in patients with fibromyalgia: An 8-week, multicenter, randomized, double-blind, placebo-controlled study

BACKGROUND

Esreboxetine is an investigational, highly selective norepinephrine reuptake inhibitor that has been reported to have antinociceptive effects in preclinical pain models.

OBJECTIVE

This study assessed the efficacy and safety profile of esreboxetine in the management of fibromyalgia.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled trial in patients aged ≥18 years who met American College of Rheumatology criteria for fibromyalgia. Eligible patients were required to have a score ≥40 mm on the 100-mm visual analog scale of the Short-Form McGill Pain Questionnaire at screening and randomization, and a mean score ≥4 on an 11-point pain rating scale (from 0 = no pain to 10 = worst possible pain) based on the weekly mean pain score in the week before randomization. After a 1-week baseline period and a 2-week, single-blind, placebo run-in period, patients were randomized to receive esreboxetine or placebo for 8 weeks, followed by a 1-week follow-up period. Esreboxetine dosing was started at 2 mg/d and was escalated by 2 mg/d every 2 weeks until attainment of a dose of 8 mg/d or the maximum tolerated dose. The primary efficacy outcome was the change from baseline to week 8 in weekly mean pain scores, as derived from patients' daily pain ratings on the 11-point scale. Additional primary efficacy outcomes included changes in the Fibromyalgia Impact Questionnaire (FIQ) total score and the Patient Global Impression of Change (PGIC). The safety profile was evaluated based on observed and spontaneously reported adverse events, laboratory tests, and other safety measures.

RESULTS

One hundred thirty-four patients were randomized to each study group, but 1 patient in the placebo group did not receive treatment. Thus, the study population consisted of 267 patients (89.5% female; 88.4% white; mean age, ∼50 years [range, 20-84 years]). Twenty-seven patients in each group discontinued the study. Adverse events were the most common reason for discontinuation in the esreboxetine group (11 patients), compared with 3 discontinuing due to adverse events in the placebo group. Patient default (withdrawal of consent and loss to follow-up) was the most common reason for discontinuation in the placebo group (13 patients), compared with 10 in the esreboxetine group. The esreboxetine group had significantly greater improvement in the weekly mean pain score compared with the placebo group (mean [SE] change from baseline: -1.55 [0.16] vs -0.99 [0.16], respectively; P = 0.006). A significantly greater percentage of patients in the esreboxetine group reported a ≥30% reduction in pain scores compared with the placebo group (37.6% [50/133] vs 22.6% [30/133]; P = 0.004). Esreboxetine was associated with significant improvement compared with placebo in the FIQ total score (mean change from baseline: -15.63 [1.56] vs -8.07 [1.54]; P < 0.001). On the PGIC, significantly more patients in the esreboxetine group than in the placebo group reported their condition much or very much improved (odds ratio = 2.42; 90% CI, 1.549-3.786; P < 0.001). Esreboxetine also was associated with significant improvements in secondary outcomes compared with placebo. These included fatigue, as reflected in scores on the Multidimensional Assessment of Fatigue (mean [SE] change from baseline: -6.39 [0.75] vs -2.82 [0.75], respectively; P < 0.001), and scores on measures of patient function and health-related quality of life, including the 36-item Short Form Health Survey (SF-36) Physical Component Summary (mean change from baseline: 4.36 [0.59] vs 1.86 [0.59]; P = 0.002), the SF-36 Mental Component Summary (mean change from baseline: 4.25 [0.83] vs 1.81 [0.83]; P = 0.019), and the Sheehan Disability Scale total score (mean change from baseline: -6.50 [0.64] vs -2.79 [0.61]; P < 0.001). Numerically more patients in the esreboxetine group than in the placebo group reported at least one adverse event (71.6% vs 57.1%), most commonly constipation (17.2% vs 5.3%), insomnia (15.7% vs 3.0%), dry mouth (15.7% vs 2.3%), and headache (10.4% vs 2.3%).

CONCLUSIONS

In this 8-week trial in patients with fibromyalgia, esreboxetine was associated with significant reductions in pain scores compared with placebo. It was also associated with improvements in outcomes relevant to fibromyalgia, including the PGIC, function, and fatigue. ClinicalTrials.gov identifier: NCT00357825.

Flexible dosed duloxetine in the treatment of fibromyalgia: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To investigate the efficacy of flexible dose duloxetine 60-120 mg/day on changes in fibromyalgia (FM) symptoms assessed by the Patient Global Impression of Improvement (PGI-I) scale.

METHODS

Outpatients ≥ 18 years of age who met American College of Rheumatology criteria for FM, and had ≥ 4 score on the Brief Pain Inventory (BPI) average pain item, were randomized to duloxetine (n = 263) or placebo (n = 267) for 24 week double-blind treatment (primary endpoint at Week 12). Key secondary measures included BPI average pain severity, patient-rated scales assessing mood, anxiety, pain, sleep, and stiffness, Clinical Global Impression of Severity (CGI-S), Multidimensional Fatigue Inventory, Cognitive and Physical Functioning Questionnaire, Beck Depression Inventory (BDI), Beck Anxiety Inventory, and Medical Outcome Study Short-Form Health Survey (SF-36).

RESULTS

At Week 12, duloxetine-treated patients reported significantly greater global improvement with mean PGI-I scores of 2.8 compared to 3.4 in the placebo group (p < 0.001). Significantly more duloxetine- versus placebo-treated patients (57% vs 32%; p < 0.001) reported feeling "much" or "very much better" (PGI-I score ≤ 2). There was significantly greater improvement with duloxetine versus placebo treatment in BPI average pain severity, mood (including BDI total), anxiety (patient-rated only), stiffness, CGI-S, fatigue, all SF-36 domains (except role-physical and physical component summary), and being less bothered by pain or sleep difficulties. Treatment-emergent adverse events occurring significantly more frequently with duloxetine included: nausea, headache, constipation, dry mouth, dizziness, diarrhea, and hyperhidrosis.

CONCLUSION

Treatment with duloxetine 60, 90, and 120 mg/day was associated with feeling much better, pain reduction, being less bothered by sleep difficulties, and improvement in mood, stiffness, fatigue and functioning. (Clinical trial registry NCT00673452).

Actigraphy-based physical activity monitoring in adolescents with juvenile primary fibromyalgia syndrome

Juvenile primary fibromyalgia syndrome (JPFS) is a chronic pain condition associated with significant impairment in physical functioning, but no studies have used newer technologies such as actigraphy to document objective physical activity levels in JPFS. This is the first study to objectively describe physical activity in JPFS patients and examine the relationship of pain, perceived functional impairment, and depressive symptoms on physical activity. One hundred four clinically referred adolescents with JPFS (ages 11 to 18 years) wore a hip-mounted actigraph for 1 week. Data on pain intensity, functional disability, depressive symptoms, and psychiatric diagnoses were obtained using self- and parent-report measures and a standardized psychiatric interview. Results showed that younger patients were more active. Pain intensity was not significantly associated with physical activity levels overall, but the most highly active group of adolescents reported lower levels of pain and disability than the least active. Parent report of adolescents' physical functioning and depressive symptoms were significantly correlated with adolescents' physical activity levels. Actigraphy provides a unique source of information about physical functioning which is distinct from adolescents' self-report of physical functioning in JPFS. Preliminary findings suggest that further study of factors that predict perceived and actual physical functioning in JPFS is warranted.

PERSPECTIVE

This study presents the results of physical activity monitoring in adolescents with JPFS using actigraphy. Results indicate that actigraphy provides a unique source of objective information that can advance our understanding of physical disability in JPFS and the factors associated with physical impairment.

Phenomenology and therapeutic options for dermatotillomania

Dermatotillomania (also called psychogenic excoriation, neurotic excoriation, acne excoriée, skin picking and pathological or compulsive skin picking) is characterized by excessive scratching or picking of normal skin or skin with minor surface irregularities. Until recently, there have been few therapeutic options for patients with this disorder, which causes substantial distress and functional impairment in many patients. Recent pharmacological studies have found that some selective serotonin reuptake inhibitors may be effective in the treatment of this disorder. Furthermore, phenomenological studies have better characterized the heterogeneity of the behavior associated with dermatotillomania. Clinicians may now be able to develop more effective treatments for patients by targeting the specific behavioral symptoms of the disorder in individual patients.

Fibromyalgia syndrome: practical strategies for improving diagnosis and patient outcomes

Recent advances in the understanding of the etiology, epidemiology, diagnosis, and treatment of fibromyalgia must be applied in clinical practice to achieve optimal patient outcomes. Current evidence indicates that fibromyalgia is a hyperalgesic state, resulting from a generalized problem with augmented pain processing that likely results from the way the spinal cord and the brain process pain and other sensory information. The descending pain pathway involving serotonin, norepinephrine, and dopamine, as opposed to the descending opioid pain pathway, appears to be selectively attenuated. Newer treatment options targeted at the pain mechanisms include the alpha(2)-delta pregabalin, which binds to the alpha(2)-delta subunit of voltage-gated calcium channels in neurons, and the serotonin-norepinephrine dual reuptake inhibitors duloxetine and milnacipran. The US Food and Drug Administration (FDA) has approved pregabalin, duloxetine, and milnacipran for the management of fibromyalgia. In addition to pharmacologic therapy, patient education, cognitive behavioral therapy, aerobic exercise, and strength and flexibility training are important components of care. An individualized treatment plan should be developed with consideration of each patient's unique combination of fibromyalgia symptoms, functional level, and the presence of the comorbid psychiatric and medical conditions that are common in patients with fibromyalgia. This educational activity provides clinicians with the tools necessary to differentiate fibromyalgia syndrome from other chronic pain conditions through a review of recent clinical data and an application of an advanced understanding of pain pathways. Strategies to manage patients with comorbid conditions are explored, with an emphasis on the importance of a multidisciplinary approach to patient care. Online Access: http://www.cmeaccess.com/cme/ajm_fibro_program/

The pathophysiology, diagnosis and treatment of fibromyalgia

Research in fibromyalgia has increased understanding of the possible genetic and environmental factors that could be involved in the etiology of fibromyalgia. There is now substantial evidence for augmentation of central pain processing in fibromyalgia. Because the clinical presentation of fibromyalgia is heterogeneous, treatment recommendations must be individualized for each patient. The rapid growth of trials in fibromyalgia in recent years has resulted in new evidence-based approaches to pharmacological and nonpharmacological treatment.

Relationship between school absenteeism and depressive symptoms among adolescents with juvenile fibromyalgia

OBJECTIVE

To describe school absences in adolescents with Juvenile Primary Fibromyalgia Syndrome (JPFS) and examine the relationship between school absenteeism, pain, psychiatric symptoms, and maternal pain history.

METHODS

Adolescents with JPFS (N = 102; mean age 14.96 years) completed measures of pain and depressive symptoms, and completed a psychiatric interview. Parents provided information about the adolescents' school absences, type of schooling, and parental pain history. School attendance reports were obtained directly from schools.

RESULTS

Over 12% of adolescents with JPFS were homeschooled. Those enrolled in regular school missed 2.9 days per month on average, with one-third of participants missing more than 3 days per month. Pain and maternal pain history were not related to school absenteeism. However, depressive symptoms were significantly associated with school absences.

CONCLUSION

Many adolescents with JPFS experience difficulties with regular school attendance. Long-term risks associated with school absenteeism and the importance of addressing psychological factors are discussed.

Fibromyalgia syndrome module at OMERACT 9: domain construct

The objective of the module was to (1) establish a core domain set for fibromyalgia (FM) assessment in clinical trials and practice, (2) review outcome measure performance characteristics, (3) discuss development of a responder index for assessment of FM in clinical trials, (4) review objective markers, (5) review the domain of cognitive dysfunction, and (6) establish a research agenda for outcomes research. Presentations at the module included: (1) Results of univariate and multivariate analysis of 10 FM clinical trials of 4 drugs, mapping key domains identified in previous patient focus group: Delphi exercises and a clinician/researcher Delphi exercise, and breakout discussions to vote on possible essential domains and reliable measures; (2) Updates regarding outcome measure status; (3) Update on objective markers to measure FM disease state; and (4) Review of the issue of cognitive dysfunction (dyscognition) in FM. Consensus was reached as follows: (1) Greater than 70% of OMERACT participants agreed that pain, tenderness, fatigue, patient global, multidimensional function and sleep disturbance domains should be measured in all FM clinical trials; dyscognition and depression should be measured in some trials; and stiffness, anxiety, functional imaging, and cerebrospinal fluid biomarkers were identified as domains of research interest. (2) FM domain outcome measures have generally proven to be reliable, discriminative, and feasible. More sophisticated and comprehensive measures are in development, as is a responder index for FM. (3) Increasing numbers of objective markers are being developed for FM assessment. (4) Cognitive dysfunction assessment by self-assessed and applied outcome measures is being developed. In conclusion, a multidimensional symptom core set is proposed for evaluation of FM in clinical trials. Research on improved measures of single domains and composite measures is ongoing.

Strategies for managing fibromyalgia

The presentation of fibromyalgia is heterogeneous, and the treatment approach should be individualized for each patient, depending on the severity of the patient's pain, the presence of other symptoms or comorbidities, and the degree of functional impairment. The management of fibromyalgia includes the identification and treatment of all pain sources that may be present in addition to fibromyalgia, such as peripheral pain generators (e.g., comorbid osteoarthritis or neuropathic pain) or visceral pain (e.g., comorbid irritable bowel syndrome). It is also important to address other symptoms or disorders that commonly occur in patients with fibromyalgia, such as fatigue, sleep disturbances, cognitive impairment, stiffness, and mood or anxiety disorders. Finally, the treatment should strive to improve the patient's function and global health status. In most cases, the management of fibromyalgia involves both pharmacologic and nonpharmacologic treatments. This report provides an in-depth review of randomized, controlled trials for pharmacologic and nonpharmacologic approaches to fibromyalgia therapy.

Content and criterion validity of the preliminary core dataset for clinical trials in fibromyalgia syndrome

OBJECTIVE

Increasing research interest and emerging new therapies for treatment of fibromyalgia (FM) have led to a need to develop a consensus on a core set of outcome measures that should be assessed and reported in all clinical trials, to facilitate interpretation of the data and understanding of the disease. This aligns with the key objective of the Outcome Measures in Rheumatology (OMERACT) initiative to improve outcome measurement through a data driven, interactive consensus process.

METHODS

Through patient focus groups and Delphi processes, working groups at previous OMERACT meetings identified potential domains to be included in the core data set. A systematic review has shown that instruments measuring these domains are available and are at least moderately sensitive to change. Most instruments have been validated in multiple languages. This pooled analysis study aims to develop the core data set by analyzing data from 10 randomized controlled trials (RCT) in FM.

RESULTS

Results from this study provide support for the inclusion of the following in the core data set: pain, tenderness, fatigue, sleep, patient global assessment, and multidimensional function/health related quality of life. Construct validity was demonstrated with outcome instruments showing convergent and divergent validity. Content and criterion validity were confirmed by multivariate analysis showing R square values between 0.4 and 0.6. Low R square value is associated with studies in which one or more domains were not assessed.

CONCLUSION

The core data set was supported by high consensus among attendees at OMERACT 9. Establishing an international standard for RCT in FM should facilitate future metaanalyses and indirect comparisons.

Pain and the brain: chronic widespread pain

Chronic widespread pain is associated with several medical and psychiatric disorders including, but not limited to, chronic fatigue syndrome, fibromyalgia, mood disorders, hepatitis, endocrine disorders such as hypothyroidism, and rheumatologic disorders such as rheumatoid arthritis. Careful and comprehensive differential diagnosis must be performed to ensure a correct diagnosis before an appropriate treatment can be selected. Fibromyalgia, in particular, is challenging to diagnose and treat because it shares many characteristics with other disorders and is commonly concurrent with major mood disorders. A comprehensive disease management strategy including patient education, pharmacotherapy, cognitive-behavioral therapy, and aerobic and other forms of exercise can be beneficial for many patients with fibromyalgia.

Multidisciplinary care and stepwise treatment for fibromyalgia

Fibromyalgia is a common musculoskeletal pain condition associated with chronic widespread pain, tenderness at various points on the body, fatigue, sleep abnormalities, and common comorbidity with psychiatric and medical disorders. Research into pharmacologic remedies for fibromyalgia has demonstrated efficacy for a variety of agents, but pharmacology is only one piece of the puzzle when it comes to successful management of fibromyalgia. Sensitive and appropriate methods of diagnosis and an integrated treatment plan including proper patient education, aerobic exercise, and cognitive-behavioral therapy have been shown effective in alleviating fibromyalgic symptoms. The development of a comprehensive, multidisciplinary disease management strategy is a difficult but essential challenge facing clinicians treating patients with fibromyalgia.

Evaluating and diagnosing fibromyalgia and comorbid psychiatric disorders

Fibromyalgia is a common and disabling chronic pain syndrome that is often accompanied by other chronic pain and/or psychiatric comorbidities, which impact fibromyalgia course and outcome. Although a primary care provider will likely take the lead in caring for patients with fibromyalgia, psychiatrists and other mental health professionals may play a role in the diagnosis, evaluation, and management of fibromyalgia. Psychiatrists' familiarity with many of the pharmacologic and nonpharmacologic treatments that are currently being used for fibromyalgia make them valuable partners in the multidisciplinary team of clinicians addressing fibromyalgia and its comorbidities. In this activity, experts on fibromyalgia discuss the nature of the syndrome and its diagnosis and evaluation.

Patient perspectives on the impact of fibromyalgia

OBJECTIVE

The objective of this study was to elicit and assess important symptom domains and the impact of fibromyalgia on patients' quality of life and functioning from a patient's perspective. The intention was to collect this information as part of an overall effort to overcome shortcomings of existing outcome measures in fibromyalgia.

METHODS

This was a qualitative study in which six focus group sessions with 48 women diagnosed with fibromyalgia were conducted to elicit concepts and ideas to assess the impact of fibromyalgia on their lives.

RESULTS

The focus groups conducted with fibromyalgia patients identified symptom domains that had the greatest impact on their quality of life including pain, sleep disturbance, fatigue, depression, anxiety, and cognitive impairment. Fibromyalgia had a substantial negative impact on social and occupational function. Patients reported disrupted relationships with family and friends, social isolation, reduced activities of daily living and leisure activities, avoidance of physical activity, and loss of career or inability to advance in careers or education.

CONCLUSION

The findings from the focus groups revealed that fibromyalgia has a substantial negative impact on patients' lives.

PRACTICE IMPLICATIONS

A comprehensive assessment of the multiple symptoms domains associated with fibromyalgia and the impact of fibromyalgia on multidimensional aspects of function should be a routine part of the care of fibromyalgia patients.

The effect of pain on outcomes in a trial of duloxetine treatment of major depressive disorder

BACKGROUND

Patients with major depressive disorder (MDD) frequently report one or more pain symptoms. To explore the relationship between improvement in pain symptoms and MDD treatment outcomes, we conducted a secondary analysis of an approximately 12-week, open label trial of duloxetine in MDD. The primary objective was to test the hypothesis that a greater reduction in pain was associated with a higher probability of MDD remission.

METHODS

Adults with DSM-IV MDD were enrolled in the study if they had a Hamilton Depression Scale (HAMD-17) total score of 15 or more and a Clinical Global Impression of Severity (CGI-S) score of 4 or more. The duloxetine dose of patients could be titrated on the basis of the degree of response within the range from 60 to 120 mg given QD, with 90 mg QD as an intermediate dose. Remission of major depressive disorder was defined as a HAMD-17 total score of < or = 7. Core emotional symptoms of depression were determined by the HAMD-17 Maier subscale. Pain was assessed using a 100 mm visual analog scale (VAS) of overall pain severity over the last week (0 = no pain, 100 = pain as severe as I can imagine). For the primary analysis, mean change in VAS overall pain score over time was compared between remitters and non-remitters at endpoint using a mixed model repeated measures approach.

RESULTS

Two hundred forty nine patients were included in the analysis. A greater reduction in pain was associated with a significantly higher probability of remission of MDD, after accounting for changes in the core emotional symptoms. Greater pain reduction was associated with significant improvement in MDD core emotional symptoms. A greater improvement in pain was also associated with improvements in patient and clinician-rated global assessments.

CONCLUSIONS

The effective treatment of pain symptoms in patients with major depressive disorder was associated with higher remission rates. The results underscore the importance of effectively treating painful symptoms associated with depression.

Pain and the brain

Chronic pain is difficult to diagnose and treat, and is often comorbid with psychiatric conditions. Pain and mood disorders may share neurologic pathways and a neurochemical base. For example, depression is associated with abnormalities in serotonin and norepinephrine, neurotransmitters that also modulate the endogenous analgesic system. Further, co-occurring depression and pain may obscure a diagnosis of the other, secondary condition. Agents that inhibit pain signals and boost serotonin and norepinephrine levels, such as serotonin-norepinephrine reuptake inhibitors (SNRIs), may provide pain relief as well as alleviate psychiatric symptom. Psychotherapies and education should also be considered to help patients achieve optimal functioning. The pathophysiology, diagnosis, and treatment of pain and mood disorders are discussed in this video, which features case studies of and expert commentary on patients with diabetic neuropathy, lower back pain, and chronic widespread pain.

Identifying the clinical domains of fibromyalgia: contributions from clinician and patient Delphi exercises

OBJECTIVE

In evaluating the effectiveness of fibromyalgia (FM) therapies, it is important to assess the impact of those therapies on the full array of domains considered important by both clinicians and patients. The objective of this research was to identify and prioritize the key clinically relevant and important domains impacted by FM that should be evaluated by outcome assessment instruments used in FM clinical trials, and to approach consensus among clinicians and patients on the priority of those domains to be assessed in clinical care and research.

METHODS

Group consensus was achieved using the Delphi method, a structured process of consensus building via questionnaires together with systematic and controlled opinion feedback. The Delphi exercises involved 23 clinicians with expertise in FM and 100 patients with FM as defined by American College of Rheumatology criteria.

RESULTS

The Delphi exercise revealed that the domains ranked most highly by patients were similar to the domain rankings by clinicians. Pain was consistently ranked highest by both panels. Fatigue, impact on sleep, health-related quality of life, comorbid depression, and cognitive difficulty were also ranked highly. Stiffness was ranked highly by patients but not clinicians. In contrast, side effects was important to clinicians but was not identified as important in the patient Delphi exercise.

CONCLUSION

The clinician and patient Delphi exercises identified and ranked key domains that need to be assessed in FM research. Based on these results, a conceptual framework for measuring patient-reported outcomes is proposed.

Management of fibromyalgia and comorbid psychiatric disorders

According to the American College of Rheumatology, fibromyalgia is widespread pain of at least 3 months' duration in combination with pain at 11 or more of 18 specific tender point sites on the body. Many individuals with fibromyalgia also have comorbid psychiatric disorders, which can present diagnostic dilemmas and require additional treatment considerations to optimize patient outcomes. Fibromyalgia has been found to be strongly associated with depressive and anxiety symptoms, a personal or family history of depression, and accompanying antidepressant treatment. Psychiatric comorbidities negatively impact the severity and course of fibromyalgia. Pharmacotherapy can be employed to control fibromyalgia and comorbid mood and anxiety disorders. Additionally, nonpharmacologic therapies for fibromyalgia and comorbid psychiatric disorders include cognitive-behavioral therapy and aerobic exercise. The efficacy of pharmacologic and nonpharmacologic treatments is examined in this article, as well as the diagnostic difficulties that comorbid disorders present.

Efficacy and safety of duloxetine for treatment of fibromyalgia in patients with or without major depressive disorder: Results from a 6-month, randomized, double-blind, placebo-controlled, fixed-dose trial

The primary objectives of this study were to assess the efficacy and safety of duloxetine for reducing pain severity in fibromyalgia patients with or without current major depressive disorder. This was a 6-month, multicenter, randomized, double-blind, placebo-controlled study. In total, 520 patients meeting American College of Rheumatology criteria for fibromyalgia were randomly assigned to duloxetine (20 mg/day, 60 mg/day, or 120 mg/day) or placebo, administered once daily, for 6 months (after 3 months, the duloxetine 20-mg/day group titrated to 60 mg/day). The co-primary outcome measures were the Brief Pain Inventory (BPI) average pain severity score and Patient Global Impressions of Improvement (PGI-I) score. Safety was assessed via treatment-emergent adverse events, and changes in vital sign, laboratory, and ECG measures. Compared with placebo-treated patients, those patients treated with duloxetine 120 mg/day improved significantly more on the co-primary outcome measures at 3 months (change in BPI score [-2.31 vs -1.39, P<0.001] and PGI-I [2.89 vs 3.39, P=0.004]) and at 6 months (change in BPI [-2.26 vs -1.43, P=0.003] and PGI-I [2.93 vs 3.37, P=0.012]). Compared with placebo, treatment with duloxetine 60 mg/day also significantly improved the co-primary measures at 3 months and BPI at 6 months. Duloxetine was efficacious in patients both with and without major depressive disorder. There were no clinically significant differences between treatment groups in changes in vital signs, laboratory measures, or ECG measures. Study results demonstrated that duloxetine at doses of 60 mg/day and 120 mg/day appears to be safe and efficacious in patients with fibromyalgia.

A randomized, double-blind, placebo-controlled, phase III trial of pregabalin in the treatment of patients with fibromyalgia

OBJECTIVE

To evaluate the efficacy and safety of pregabalin for symptomatic relief of pain associated with fibromyalgia (FM) and for management of FM.

METHODS

This multicenter, double-blind, placebo-controlled trial randomly assigned 748 patients with FM to receive placebo or pregabalin 300, 450, or 600 mg/day (dosed twice daily) for 13 weeks. The primary outcome variable for study objective 1, symptomatic relief of pain associated with FM, was comparison of endpoint mean pain scores between each pregabalin group and placebo. The outcome variable for study objective 2, management of FM, included endpoint mean pain scores, Patient Global Impression of Change (PGIC), and Fibromyalgia Impact Questionnaire (FIQ)-Total Score. Secondary outcomes included assessments of sleep, fatigue, and mood disturbance.

RESULTS

Patients in all pregabalin groups showed statistically significant improvement in endpoint mean pain score and in PGIC response compared with placebo. Improvements in FIQ-Total Score for the pregabalin groups were numerically but not significantly greater than those for the placebo group. Compared with placebo, all pregabalin treatment groups showed statistically significant improvement in assessments of sleep and in patients' impressions of their global improvement. Dizziness and somnolence were the most frequently reported adverse events.

CONCLUSION

Pregabalin at 300, 450, and 600 mg/day was efficacious and safe for treatment of pain associated with FM. Pregabalin monotherapy provides clinically meaningful benefit to patients with FM.