A cost-consequence analysis of pregabalin versus usual care in the symptomatic treatment of refractory low back pain: sub-analysis of observational trial data from orthopaedic surgery and rehabilitation clinics

CDC Clinical Practice Guideline for Prescribing Opioids for Pain - United States, 2022

This guideline provides recommendations for clinicians providing pain care, including those prescribing opioids, for outpatients aged ≥18 years. It updates the CDC Guideline for Prescribing Opioids for Chronic Pain - United States, 2016 (MMWR Recomm Rep 2016;65[No. RR-1]:1-49) and includes recommendations for managing acute (duration of <1 month), subacute (duration of 1-3 months), and chronic (duration of >3 months) pain. The recommendations do not apply to pain related to sickle cell disease or cancer or to patients receiving palliative or end-of-life care. The guideline addresses the following four areas: 1) determining whether or not to initiate opioids for pain, 2) selecting opioids and determining opioid dosages, 3) deciding duration of initial opioid prescription and conducting follow-up, and 4) assessing risk and addressing potential harms of opioid use. CDC developed the guideline using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Recommendations are based on systematic reviews of the scientific evidence and reflect considerations of benefits and harms, patient and clinician values and preferences, and resource allocation. CDC obtained input from the Board of Scientific Counselors of the National Center for Injury Prevention and Control (a federally chartered advisory committee), the public, and peer reviewers. CDC recommends that persons with pain receive appropriate pain treatment, with careful consideration of the benefits and risks of all treatment options in the context of the patient's circumstances. Recommendations should not be applied as inflexible standards of care across patient populations. This clinical practice guideline is intended to improve communication between clinicians and patients about the benefits and risks of pain treatments, including opioid therapy; improve the effectiveness and safety of pain treatment; mitigate pain; improve function and quality of life for patients with pain; and reduce risks associated with opioid pain therapy, including opioid use disorder, overdose, and death.

The effectiveness of pregabalin with or without agomelatine in the treatment of chronic low back pain: a double-blind, placebo-controlled, randomized clinical trial

BACKGROUND

Although various pharmacological and nonpharmacological treatments are available for the chronic low back pain (CLBP), there is no consensus on the best optimal treatment for this condition. This study aimed to investigate the efficacy of co-administration of pregabalin and agomelatine versus pregabalin with placebo to treat CLBP.

METHODS

Forty-six CLBP patients without the surgical indication referred to the outpatient orthopedic clinic of Rasoul-e-Akram Hospital, Tehran, Iran, were randomly divided into two study groups: Group A [pregabalin (75 mg twice per day) + placebo] and Group B [pregabalin (75 mg twice per day) + agomelatine (25 mg per night)]. Patients were evaluated at weeks 0, 4, and 8. Outcome measures were the Persian versions of the Brief Pain Inventory (BPI) interference scale, Roland-Morris Disability Questionnaire (RMDQ), The Hospital Anxiety and Depression Scale (HADS), 36-Item Short Form Survey (SF-36), and General Health Questionnaire-28 (GHQ-28) were used.

RESULTS

At weeks 4 and 8 after the intervention, all evaluated measures showed significant improvement in both study groups (P < 0.01). The mean improvement of GHQ-28 was 3.7 ± 1.22 in group A and 13.1 ± 4.71 in group B. This difference was statistically significant (P = 0.003). Other outcomes did not vary substantially between the two research groups. Agomelatine treatment was well tolerated, with no significant adverse effects seen in patients. Liver tests of all patients were routine during the study period. Major adverse effect was not seen in any patient. The prevalence of Minor side effects was not significantly different between two study groups.

CONCLUSION

Compared with the pregabalin and placebo, co-administration of pregabalin and agomelatine had no added effect on improving pain scores in CLBP patients. However, the patients' general health was significantly improved after the combined administration of pregabalin and agomelatine.

TRIAL REGISTRATION

The study protocol was registered in the Iranian Registry of Clinical Trials before starting the study (NO.IRCT20200620047852N1, Registration date: 23/06/2020).

Pharmacotherapy for Spine-Related Pain in Older Adults

As the population ages, spine-related pain is increasingly common in older adults. While medications play an important role in pain management, their use has limitations in geriatric patients due to reduced liver and renal function, comorbid medical problems, and polypharmacy. This review will assess the evidence basis for medications used for spine-related pain in older adults, with a focus on drug metabolism and adverse drug reactions. A PubMed/OVID search crossing common spine, neck, and back pain terms with key words for older adults and geriatrics was combined with common drug classes and common drug names and limited to clinical trials and age over 65 years. The results were then reviewed with identification of commonly used drugs and drug categories: nonsteroidal anti-inflammatories (NSAIDs), acetaminophen, corticosteroids, gabapentin and pregabalin, antispastic and antispasmodic muscle relaxants, tricyclic antidepressants (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tramadol, and opioids. Collectively, 138 double-blind, placebo-controlled trials were the focus of the review. The review found a variable contribution of high-quality studies examining the efficacy of medications for spine pain primarily in the geriatric population. There was strong evidence for NSAID use with adjustments for gastrointestinal and renal risk factors. Gabapentin and pregabalin had mixed evidence for neuropathic pain. SNRIs had good evidence for neuropathic pain and a more favorable safety profile than TCAs. Tramadol had some evidence in older patients, but more so in persons aged < 65 years. Rational therapeutic choices based on geriatric spine pain diagnosis are helpful, such as NSAIDs and acetaminophen for arthritic and myofascial-based pain, gabapentinoids or duloxetine for neuropathic and radicular pain, antispastic agents for myofascial-based pain, and combination therapy for mixed etiologies. Tramadol can be well tolerated in older patients, but has risks of cognitive and classic opioid side effects. Otherwise, opioids are typically avoided in the treatment of spine-related pain in older adults due to their morbidity and mortality risk and are reserved for refractory severe pain. Whenever possible, beneficial geriatric spine pain pharmacotherapy should employ the lowest therapeutic doses with consideration of polypharmacy, potentially decreased renal and hepatic metabolism, and co-morbid medical disorders.

Effectiveness of Pregabalin Treatment for Neuropathic Pain in Patients with Spine Diseases: A Pooled Analysis of Two Multicenter Observational Studies in Japan

Purpose

Neuropathic pain (NeP) is common among patients with chronic pain associated with spine diseases. Practical effectiveness of pregabalin, one of the first-line treatments for NeP, has not been evaluated in an entire population of patients with spine diseases, including various pathophysiological conditions. This pooled analysis aimed to evaluate the therapeutic value of pregabalin for chronic pain with NeP component in patients with spine diseases in routine primary care settings.

Patients and Methods

We pooled data from two 8-week prospective observational cohort studies for patients with chronic low back pain with accompanying lower limb pain (NeP component), and patients with chronic cervical pain and accompanying upper limb radiating pain (NeP component) in routine primary care settings in Japan. For both studies, patients were treated for 8 weeks with pregabalin (alone/with other analgesics) or usual care with conventional analgesics (eg, non-steroidal anti-inflammatory drugs). Changes in pain numerical rating scale (NRS), Pain-Related Sleep Interference Scale (PRSIS), and EuroQol 5-dimension 5-level (EQ-5D-5L) scores from baseline to week 8 were summarized and compared between the pregabalin and usual care groups, and also for subgroups of primary diagnosis. Safety was evaluated by adverse events (AEs) in the pregabalin group.

Results

The pooled dataset comprised 700 patients (pregabalin group: 302; usual care group: 398). All patient-reported outcomes (PRO) scores significantly improved from baseline to week 8 in the pregabalin than in the usual care group (NRS: P<0.0001; PRSIS: P<0.0001, and EQ-5D-5L: P=0.0006). Overall, all three PRO measures showed greater improvement in the pregabalin than in the usual care group, irrespective of the primary diagnosis. AEs were reported in 36.1% of the pregabalin group.

Conclusion

This analysis suggested multi-faceted effectiveness of treatment with pregabalin from the patient’s perspectives under a “real-world” practice in all patients with chronic NeP from various spine diseases.

Cost-effectiveness analysis of the pharmacological management of chronic low back pain with four leading drugs

BACKGROUND

Chronic low back pain is a major health problem that has a substantial effect on people's quality of life and places a significant economic burden on healthcare systems. However, there has been little cost-effectiveness analysis of the treatments for it. Therefore, the purpose of this prospective observational study was to evaluate the cost-effectiveness of the pharmacological management of chronic low back pain.

METHODS

A total of 474 patients received pharmacological management for chronic low back pain using four leading drugs for 6 months at 28 institutions in Japan. Outcome measures, including EQ-5D, the Japanese Orthopaedic Association (JOA) score, the JOA back pain evaluation questionnaire (BPEQ), the Roland-Morris Disability Questionnaire, the Medical Outcomes Study SF-8, and the visual analog scale, were investigated at baseline and every one month thereafter. The incremental cost-utility ratio (ICUR) was calculated as drug cost over the quality-adjusted life years. An economic estimation was performed from the perspective of a public healthcare payer in Japan. Stratified analysis based on patient characteristics was also performed to explore the characteristics that affect cost-effectiveness.

RESULTS

The ICUR of pharmacological management for chronic low back pain was JPY 453,756. Stratified analysis based on patient characteristics suggested that the pharmacological treatments for patients with a history of spine surgery or cancer, low frequency of exercise, long disease period, low scores in lumbar spine dysfunction and gait disturbance of the JOA BPEQ, and low JOA score at baseline were not cost-effective.

CONCLUSIONS

Pharmacological management for chronic low back pain is cost-effective from the reference willingness to pay. Further optimization based on patient characteristics is expected to contribute to the sustainable development of a universal insurance system in Japan.

Reproducibility of a battery of human evoked pain models to detect pharmacological effects of analgesic drugs

BACKGROUND

Although reproducibility is considered essential for any method used in scientific research, it is investigated only rarely; thus, strikingly little has been published regarding the reproducibility of evoked pain models involving human subjects. Here, we studied the reproducibility of a battery of evoked pain models for demonstrating the analgesic effects of two analgesic compounds.

METHODS

A total of 81 healthy subjects participated in four studies involving a battery of evoked pain tests in which mechanical, thermal and electrical stimuli were used to measure pain detection and tolerance thresholds. Pharmacodynamic outcome variables were analysed using a mixed model analysis of variance, and a coefficient of variation was calculated by dividing the standard deviation by the least squares means.

RESULTS

A total of 76 subjects completed the studies. After being administered pregabalin, the subjects' pain tolerance thresholds in the cold pressor and pressure stimulation tests were significantly increased compared to the placebo group. Moreover, the heat pain detection threshold in UVB-irradiated skin was significantly increased in subjects who were administered ibuprofen compared to the placebo group. Variation among all evoked pain tests ranged from 2.2% to 30.6%.

CONCLUSIONS

Four studies using a similar design showed reproducibility with respect to the included evoked pain models. The relatively high consistency and reproducibility of two analgesics at doses known to be effective in treating clinically relevant pain supports the validity of using this pain test battery to investigate the analgesic activity and determine the active dosage of putative analgesic compounds in early clinical development.

SIGNIFICANCE

The consistency and reproducibility of measuring the profile of an analgesic at clinically relevant doses illustrates that this pain test battery is a valid tool for demonstrating the analgesic activity of a test compound and for determining the optimal active dose in early clinical drug development.

Cost-effectiveness analysis of pregabalin for treatment of chronic low back pain in patients with accompanying lower limb pain (neuropathic component) in Japan

OBJECTIVE

To assess the cost-effectiveness of pregabalin for the treatment of chronic low back pain with accompanying neuropathic pain (CLBP-NeP) from the health care payer and societal perspectives.

METHODS

The cost-effectiveness of pregabalin versus usual care for treatment of CLBP-NeP was evaluated over a 12-month time horizon using the incremental cost-effectiveness ratio (ICER). Quality-adjusted life years (QALYs), derived from the five-dimension, five-level EuroQol (EQ-5D-5L) questionnaire, was the measure of effectiveness. Medical costs and productivity losses were both calculated. Expected costs and outcomes were estimated via cohort simulation using a state-transition model, which mimics pain state transitions among mild, moderate, and severe pain. Distributions of pain severity were obtained from an 8-week noninterventional study. Health care resource consumption for estimation of direct medical costs for pain severity levels was derived from a physician survey. The ICER per additional QALY gained was calculated and sensitivity analyses were performed to evaluate the robustness of the assumptions across a range of values.

RESULTS

Direct medical costs and hospitalization costs were both lower in the pregabalin arm compared with usual care. The estimated ICERs in the base case scenarios were approximately ¥2,025,000 and ¥1,435,000 per QALY gained with pregabalin from the payer and societal perspectives, respectively; the latter included indirect costs related to lost productivity. Sensitivity analyses using alternate values for postsurgical pain scores (0 and 5), initial pain severity levels (either all moderate or all severe), and the actual EQ-5D-5L scores from the noninterventional study showed robustness of results, with ICERs that were similar to the base case. Development of a cost-effectiveness acceptability curve showed high probability (≥75%) of pregabalin being cost-effective.

CONCLUSION

Using data and assumptions from routine clinical practice, pregabalin is cost-effective for the treatment of CLBP-NeP in Japan.

Effectiveness of pregabalin for the treatment of chronic low back pain with accompanying lower limb pain (neuropathic component): a non-interventional study in Japan

Objective

To evaluate the impact of pregabalin on sleep, pain, function, and health status in patients with chronic low back pain with accompanying neuropathic pain (CLBP-NeP) under routine clinical practice.

Methods

This prospective, non-interventional, observational study enrolled Japanese adults (≥18 years) with CLBP-NeP of duration ≥3 months and severity ≥5 on a numerical rating scale (0= no pain, 10= worst possible pain). Treatment was 8 weeks with pregabalin (n=157) or usual care alone (n=174); choice of treatment was determined by the physician. The primary efficacy outcome was change from baseline to 8 weeks in pain-related interference with sleep, assessed using the Pain-Related Sleep Interference Scale (PRSIS; 0= did not interfere with sleep, 10= completely interferes with sleep). Secondary endpoints were changes in PRSIS at week 4, and changes at weeks 4 and 8 in pain (numerical rating scale), function (Roland-Morris Disability Questionnaire), and quality of life (EuroQol 5D-5L); global assessments of change were evaluated from the clinician and patient perspectives at the final visit.

Results

Demographic characteristics were similar between cohorts, but clinical characteristics suggested greater disease severity in the pregabalin group including a higher mean (standard deviation) pain score, 6.3 (1.2) versus 5.8 (1.1) (P<0.001). For the primary endpoint, pregabalin resulted in significantly greater improvements in PRSIS at week 8, least-squares mean changes of −1.3 versus −0.4 for usual care (P<0.001); pregabalin also resulted in greater PRSIS improvement at week 4 (P=0.012). Relative to usual care at week 8, pregabalin improved pain and function (both P<0.001), and showed global improvements since beginning study medication (P<0.001). Pregabalin was well tolerated.

Conclusion

In clinical practice in patients with CLBP-NeP, pregabalin showed significantly greater improvements in pain-related interference with sleep relative to usual care. In addition, pregabalin significantly improved pain, function, and health status, suggesting the benefits of pregabalin for overall health and well-being relative to usual care in these patients. (Clinicaltrials. gov identifier NCT02273908).

Add-on treatment with pregabalin for patients with uncontrolled neuropathic pain who have been referred to pain clinics

OBJECTIVE

The aim of this study was to investigate the impact of pregabalin on pain, other symptoms, and patient-reported outcomes for patients with uncontrolled pain who have been referred to pain clinics.

PATIENTS AND METHODS

Adult patients with uncontrolled pain who had a score of ≥4 in the DN4 questionnaire were evaluated at baseline, month 3, and month 6. Evaluations included pain levels using a visual analog (VAS) scale as well as anxiety, depression, sleep, disability, and treatment satisfaction employing validated tools.

RESULTS

Our sample comprised 413 patients who met the selection criteria, had not received pregabalin previously, and were prescribed pregabalin at the study initiation, mainly (97 %) as add-on therapy. Overall, patients had a statistically significant reduction in VAS pain score of 41 points (54 % reduction, p < 0.001), varying from 64 % reduction (oncological pain) to 31 % reduction (central neuropathic pain). Effect sizes for anxiety, depression, sleep, and treatment satisfaction improvement were moderate to large depending on the dimension and clinical entity.

CONCLUSION

Our results suggest that in patients with uncontrolled neuropathic pain of various origins who were treated at pain clinics, the addition of pregabalin to a wider pharmacological treatment regimen was associated with a clinically relevant improvement of pain and psychological well-being and a reduction in the impact of neuropathic pain on daily activities. Add-on treatment with pregabalin was well tolerated.

Pharmacological management of chronic lower back pain: a review of cost effectiveness

Lower back pain is one of the most prevalent musculoskeletal conditions in the developed world and accounts for significant health services use. The American College of Physicians and the American Pain Society have published a joint clinical guideline that recommends providing patients with information on prognosis and self-management, the use of medications with proven benefits and, for those who do not improve, consideration be given to the use of spinal manipulation (for acute lower back pain only), interdisciplinary rehabilitation, exercise, acupuncture, massage, yoga, cognitive behavioural therapy or relaxation. The purpose of this review was to evaluate published economic evaluations of pharmacological management for chronic lower back pain. A total of seven studies were eligible for inclusion in there view. The quality of the economic evaluations undertaken in the included studies was not high. This was primarily because of the nature of the underlying clinical evidence, most of which did not come from rigorous randomised controlled trials (RCTs), and the manner in which it was incorporated into the economic evaluations. All studies provided reasonable information about what aspects of healthcare and other resource use were identified, measured and valued. However, the reporting of total costs was not uniform across studies. Measures of pain and disability were the most commonly collected outcomes measures. Two studies collected information on quality of life directly from participants while two studies modelled this information based on the literature. Future economic evaluations of interventions for chronic lower back pain, including pharmacological interventions, should be based on the results of well-conducted RCTs where the measurement of costs and outcomes such as quality of life and quality-adjusted life-years is included in the trial protocol, and which have a follow-up period sufficient to capture meaningful changes in both costs and outcomes. In the absence of RCT data, economic models should be used to estimate future costs and outcomes using robust methods.

Pregabalin in neuropathic pain: evidences and possible mechanisms

Pregabalin is an antagonist of voltage gated Ca2+ channels and specifically binds to alpha-2-delta subunit to produce antiepileptic and analgesic actions. It successfully alleviates the symptoms of various types of neuropathic pain and presents itself as a first line therapeutic agent with remarkable safety and efficacy. Preclinical studies in various animal models of neuropathic pain have shown its effectiveness in treating the symptoms like allodynia and hyperalgesia. Clinical studies in different age groups and in different types of neuropathic pain (peripheral diabetic neuropathy, fibromyalgia, post-herpetic neuralgia, cancer chemotherapy-induced neuropathic pain) have projected it as the most effective agent either as monotherapy or in combined regimens in terms of cost effectiveness, tolerability and overall improvement in neuropathic pain states. Preclinical studies employing pregabalin in different neuropathic pain models have explored various molecular targets and the signaling systems including Ca2+ channel-mediated neurotransmitter release, activation of excitatory amino acid transporters (EAATs), potassium channels and inhibition of pathways involving inflammatory mediators. The present review summarizes the important aspects of pregabalin as analgesic in preclinical and clinical studies as well as focuses on the possible mechanisms.

Pharmacoeconomic outcomes for pregabalin: a systematic review in neuropathic pain, generalized anxiety disorder, and epilepsy from a Spanish perspective

INTRODUCTION

Pregabalin is an anticonvulsant approved in Europe for the treatment of neuropathic pain, as an adjunct therapy for epileptic seizures, and recently for generalized anxiety disorder. The aim of this study was to conduct a systematic review to evaluate the cost-effectiveness of pregabalin associated with the treatment of its labeled indications from a societal perspective in Spain.

METHODS

Data from the MEDLINE database were searched using algorithms to identify relevant economic evaluations published in English or Spanish on pregabalin for the management of neuropathic pain, generalized anxiety disorder (GAD), and epilepsy in Spanish patients over the last 10 years.

RESULTS

In total, 52 potentially relevant abstracts were identified from the MEDLINE database. Twenty manuscripts met the inclusion criteria. The majority of the selected papers (14/20) evaluated pregabalin for neuropathic pain from a societal perspective in Spain (5 economic models of pregabalin vs. gabapentin, 4 economic analyses of pregabalin in comparison with usual care, 4 economic evaluations comparing pregabalin monotherapy with add-on strategies, and one that evaluated different times of initiating pregabalin therapy). Five studies analyzed the use of pregabalin in Spain for the management of GAD (one cost-effectiveness model that compared pregabalin with venlafaxine, 2 secondary analyses in benzodiazepine-refractory patients, and 2 studies evaluating pregabalin vs. usual care in patients refractory to standard regimens). The last manuscript described a cost-effectiveness model that compared pregabalin versus levetiracetam use for the treatment of refractory partial epilepsy.

CONCLUSION

The majority of published evidence supports the possibility that pregabalin could be a cost-effective and/or cost-saving alternative for the treatment of refractory epilepsy, GAD, and neuropathic pain, in both treatment-naïve patients and in those who have demonstrated inadequate response or intolerance to previous therapy.

Effect of pregabalin in the treatment of refractory neck pain: cost and clinical evidence from medical practice in orthopedic surgery and rehabilitation clinics

BACKGROUND

The study aims to prospectively analyze the effect of adding pregabalin upon costs and consequences in the treatment of refractory neck pain under routine medical practice.

METHODS

A secondary analysis was carried out including patients over 18 years, with 6-month chronic neck pain refractory from a prospective, naturalistic, 12-week two-visit study. The analysis compared patients adding pregabalin to its therapy vs. usual care. Severity of pain, healthcare resources utilization, lost workday equivalents (LWDE) because of pain, and related cost-adjusted reductions were assessed.

RESULTS

A total of 312 patients (65.3% women, age 54.2 [12.1] years), 78.2% receiving pregabalin, were analyzed. Adding pregabalin was associated with higher adjusted reduction in pain severity: -3.2 (1.8) points, 55.4% responders (≥50% baseline pain reduction) vs. -2.3 (2.0) and 38.2%, respectively; P<0.001, yielding a higher reduction in mean LWDE: 20.1 (23.1) vs. 8.2 (22.4); P=0.014, which produced significant reductions in the indirect components of cost: €1,041.0 (1,222.8) vs. €457.3 (1,132.1), P=0.028. The costs of pregabalin (€309.8 [193.2] vs. €26.4 [79.6], P<0.001) was offset by higher numerical reductions in the other components of costs, producing similar direct cost reductions in both groups at the end of the study: €66.8 (1,080.8) and €143.5 (1,922.4), respectively; P=0.295.

CONCLUSION

Compared with usual care, the addition of pregabalin to treat refractory neck pain seems to be associated with a higher reduction in pain severity and lost work-days equivalents, which in turn results in a greater reduction of the indirect components of cost while maintaining similar healthcare cost levels despite its higher price.