A cost-consequences analysis of the effect of pregabalin in the treatment of peripheral neuropathic pain in routine medical practice in primary care settings

Role of the neuroendocrine antimicrobial peptide catestatin in innate immunity and pain

Catestatin (CST) is a neuroendocrine peptide which is derived from the chromogranin A. It has been demonstrated that CST can affect a wide range of processes, such as innate immunity, inflammatory and autoimmune reactions, and several homeostatic regulations. Furthermore, CST is positive against several kinds of bacterial strains at micromolecular range, which shows its antimicrobial activity. Recently, the role of CST in acute and chronic pain has attracted much attention. In this review, we discussed the latest research findings of CST and its role in innate immunity and pain.

Use and satisfaction with the Healthcare System of the chronic pain patients in Spain: results from a nationwide study

OBJECTIVE

To analyze the use of healthcare resources by chronic pain (CP) patients in Spain and their satisfaction with them.

RESEARCH DESIGN AND METHODS

A nationwide, cross-sectional study was carried out on a representative sample of 1957 Spanish adults. A telephone survey was conducted with the aim of analyzing the prevalence of CP, the characteristics and consequences of pain, the use of healthcare resources and patients' satisfaction with them. Descriptive, bivariate and multivariate analyses were performed.

RESULTS

Of the 1957 subjects interviewed, 325 suffered CP. The mean duration of CP was 10 years (SD: 11.3) and 48.9% of the CP sufferers reported severe/unbearable pain. Moreover, about 30% felt sad/very sad or anxious/very anxious, 24.4% had been on sick leave, 12% had left/lost their jobs and 47.2% considered their pain affected their families. Likewise, 92.9% had consulted a healthcare professional due to their CP, on average 3.49 times (SD: 3.9), and 69.2% took medication. In addition, 67.3% and 63.8% were satisfied/very satisfied with the care and the healthcare information they received, respectively. Individuals who reported headache (OR = 0.34) and feeling sad (OR =0.38) were least satisfied with the care they received. In addition, CP sufferers who made greater use of consultations were those who had left/lost their jobs (β = 1.44), those who took medication (β = 1.67), those who considered their pain affected their families (β = 0.97) and those with a shorter duration of pain (β = -0.003).

CONCLUSIONS

CP produces relevant demands on healthcare resources, conditioned by the consequences within the family and the effects on their employment. To achieve greater patient satisfaction, professionals need to pay particular attention to certain sites of pain and to patients' mental health.

Neuroprotective Effect of Matrine in Mouse Model of Vincristine-Induced Neuropathic Pain

Chemotherapy drugs such as vincristine (VCR) can cause neuropathic pain, and there is still lack of ideal strategy to treat it. The current study was designed to investigate effect of matrine (MT) on VCR-induced neuropathic pain in animal model. VCR (75 μg/kg, i.p. for 10 consecutive days) was administered to induce painful neuropathy model in mice. MT (15, 30 and 60 mg/kg, i.p.) and pregabalin (10 mg/kg, i.p.) were administered for 11 consecutive days. Various tests were performed to assess the degree of pain at different days (1, 6, 11, 16, and 21). Von Frey hair, hot plate, cold-plate and paw pressure tests were conducted to assess the degree of mechanical allodynia, thermal hyperalgesia, cold allodynia and mechanical hyperalgesia in the hind paw respectively. The electrophysiological and histopathological changes were also analyzed. Furthermore, tissue malondialdehyde (MDA), total antioxidant capacity (T-AOC),superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total calcium (TCA), myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10) were measured to investigate possible involvement of MT in inflammation and oxidative stress. Administration of MT attenuated the VCR-induced behavioral alterations as well as electrophysiological and histopathological changes in a dose dependent manner. Further, MT also attenuated the VCR-induced oxidative stress (MDA, T-AOC, GSH-Px, SOD and TCA) and inflammation (MPO, TNF-α, IL-6 and IL-10). Taken together, MT ameliorated VCR-induced painful neuropathy, which might be attributed to neuroprotective effects by subsequent reduction in oxidative stress and anti-inflammatory actions.

Antinociceptive effects of gentiopicroside on neuropathic pain induced by chronic constriction injury in mice: a behavioral and electrophysiological study

Gentiopicroside (Gent) is promising as an important protective secoiridoid compound against pain. The present study was designed to investigate whether administration of Gent would alleviate the expression of nociceptive behaviors and whether it would cause the relevant electrophysiological changes in a chronic constriction injury (CCI) model of neuropathic pain in mice. Gent was administered from the seventh day after surgery for 8 consecutive days. Behavioral parameters and sciatic functional index were assessed immediately before surgery and on days 7, 8, 10, 12, and 14 post-CCI, and electrophysiological activities of sciatic nerve were recorded immediately after the behavioral test on the last day. The present study has shown that administration of Gent (at a dose of 50 and 100 mg/kg) increased behavioral parameters from day 8 compared with the CCI-NS group. Electrophysiological data indicated that CCI caused a significant reduction in nerve conduction velocities in the sciatic nerves and the amplitudes of compound action potential, while Gent at a dose of 50 or 100 mg/kg caused a significant recovery of electrophysiological changes induced by CCI. Our data indicated that Gent has antinociceptive effects on neuropathic pain induced by CCI.

Modeling the predictive value of pain intensity on costs and resources utilization in patients with peripheral neuropathic pain

OBJECTIVE

The aim of the present analysis was to model the association and predictive value of pain intensity on cost and resource utilization in patients with chronic peripheral neuropathic pain (PNP) treated in routine clinical practice settings in Spain.

METHODS

We performed a secondary economic analysis based on data from a multicenter, observational, and prospective cost-of-illness study in patients with chronic PNP that is refractory to prior treatment. Pain intensity was measured using the Short-Form McGill Pain Questionnaire. Univariate and multivariate linear regression models were fitted to identify independent predictors of cost and health care/non-health care resource utilization.

RESULTS

A total of 1703 patients were included in the current analysis. Pain intensity was an independent predictor of total costs ([total costs]=35.6 [pain intensity]+214.5; coefficient of determination [R(2)]=0.19, P<0.001), direct costs ([direct costs]=10.8 [pain intensity]+257.7; R=0.06, P<0.001), and indirect costs ([indirect costs]=24.8 [pain intensity]-43.4; R(2)=0.20, P<0.001) related to chronic PNP in the univariate analysis. Pain intensity remains significantly associated with total costs, direct costs, and indirect costs after adjustment by other covariates in the multivariate analysis (P<0.001). None of the other variables considered in the multivariate analysis were predictors of resource utilization.

DISCUSSION

Pain intensity predicts the health care and non-health care resource utilization, and costs related to chronic PNP. Management of patients with drugs associated with a higher reduction of pain intensity may have a greater impact on the economic burden of that condition.

Capsaicin 8% patch versus oral pregabalin in patients with peripheral neuropathic pain

BACKGROUND

Clinical trials have not yet compared the efficacy of capsaicin 8% patch with current standard therapy in peripheral neuropathic pain (PNP).

OBJECTIVES

Head-to-head efficacy and safety trial comparing the capsaicin patch with pregabalin in PNP.

METHODS

Open-label, randomized, multicentre, non-inferiority trial. Patients with PNP, aged 18-80 years, were randomly assigned to either the capsaicin 8% patch (n = 282) or an optimised dose of oral pregabalin (n = 277), and assessed for a ≥30% mean decrease in Numeric Pain Rating Scale (NPRS) score from baseline to Week 8. Secondary endpoints included optimal therapeutic effect (OTE), time-to-onset of pain relief and treatment satisfaction.

RESULTS

The capsaicin 8% patch was non-inferior to pregabalin in achievement of a ≥30% mean decrease in NPRS score from baseline to Week 8 (55.7% vs. 54.5%, respectively; Odds ratio: 1.03 [95% CI: 0.72, 1.50]). The proportion of patients achieving OTE at Week 8 was 52.1% for the capsaicin 8% patch versus 44.8% for pregabalin (difference: 7.3%; 95% CI: -0.9%, 15.6%). The median time-to-onset of pain relief was significantly shorter for capsaicin 8% patch versus pregabalin (7.5 vs. 36.0 days; Hazard ratio: 1.68 [95% CI: 1.35, 2.08]; p < 0.0001). Treatment satisfaction was also significantly greater with the capsaicin 8% patch versus pregabalin. TEAEs were mild-to-moderate in severity, and resulted in treatment discontinuation only with pregabalin (n = 24). Systemic adverse drug reactions ranged from 0 to 1.1% with capsaicin 8% patch and 2.5 to 18.4% with pregabalin.

CONCLUSIONS

The capsaicin 8% patch provided non-inferior pain relief to an optimized dose of pregabalin in PNP, with a faster onset of action, fewer systemic side effects and greater treatment satisfaction.

Adding pregabalin or gabapentin for the management of community-treated patients with painful diabetic peripheral neuropathy: a comparative cost analysis

BACKGROUND AND OBJECTIVE

Painful diabetic peripheral neuropathy (pDPN) is a highly prevalent complication of diabetes mellitus, which is associated with substantial costs to society and national health systems. This economic impact varies depending on the therapeutic management provided to patients. The objective of this study was to compare healthcare resource utilization and costs among pDPN patients newly treated with pregabalin or gabapentin in routine medical practice.

METHODS

We performed a retrospective medical records study of pDPN patients newly treated with pregabalin or gabapentin as an add-on therapy who are covered by the Badalona Serveis Assistencials (BSA) health plan, a healthcare provider in Spain, from 2006 to 2009. Healthcare resource utilization and days off work were assessed. The societal perspective was used to estimate costs.

RESULTS

Three hundred and ninety-five records were eligible for analysis: 227 (57.5%) included pregabalin and 168 (42.5%) gabapentin. Mean (standard deviation) concomitant use of analgesics throughout the study was higher in the gabapentin cohort [3.9 (2.2) vs. 3.1 (2.1); p < 0.05], mainly due to greater use of non-narcotics (78.0 vs. 71.8%; p < 0.05) and opioids (32.7 vs. 28.6%; p < 0.05). Healthcare costs accounted for 59.2% of total costs, of which 71.9% occurred in primary care, with a mean cost per patient of €2,476 (year 2010 values). Adjusted mean (95% CI) total costs were significantly lower in pregabalin-treated patients [€2,003 (1,427-2,579)] than in gabapentin-treated patients [€3,127 (2,463-3,790)] (p = 0.013), mainly due to lower healthcare costs [€1,312 (1,192-1,432) vs. €1,675 (1,537-1,814); p < 0.001].

CONCLUSIONS

Adding pregabalin to existing pDPN therapy resulted in lower total healthcare costs and lower resource utilization than resulted from adding gabapentin.

Protective effect of hesperetin in rat model of partial sciatic nerve ligation induced painful neuropathic pain: an evidence of anti-inflammatory and anti-oxidative activity

Behavioral, biochemical and gene expression changes were investigated in a rat model of partial sciatic nerve ligation (PSNL) after administration of hesperetin (20, 50mg/kg; p.o.), pregabalin (10mg/kg; p.o.) or vehicle (1 ml/kg, p.o.). Thirty-six animals were randomly divided into six groups. Left sciatic nerve was exposed and ligated, animals in the control and test groups were treated orally with respective drugs for fifteen days. Nociceptive threshold was assessed on 0 day and thereafter every three days. Three weeks later, sciatic nerve tissue homogenate was prepared and subjected for estimation of oxidative markers namely total protein, nitric oxide, lipid peroxidase, interleukins (IL-1β and IL-6) and TNF-α. Administration of hesperetin resulted in a dose dependent attenuation in PSNL-induced mechanical and thermal hyperalgesia, mechanical allodynia as well as down regulation of IL-1β, IL-6 and TNF-α, and biochemical markers. Consequently, it can be concluded that anti-hyperalgesic effect of hesperetin in rats after PSNL may be attributed to various oxidative markers as well as the pro-inflammatory mediators secreted at the injury site. Hesperetin appears to be a promising candidate for the development as a novel therapeutic for the patients suffering from the neuropathic pain.

Effectiveness of pregabalin as monotherapy or combination therapy for neuropathic pain in patients unresponsive to previous treatments in a Spanish primary care setting

Background and Objective

Patients from a previous study of neuropathic pain (NP) in the Spanish primary care setting still had symptoms despite treatment. Subsequently, patients were treated as prescribed by their physician and followed up for 3 months. Since pregabalin has been shown to be effective in NP, including refractory cases, the objective of this study was to assess the effectiveness of pregabalin therapy in patients with NP refractory to previous treatments.

Methods

This was a post hoc analysis of pregabalin-naïve NP patients treated with pregabalin in a 3-month follow-up observational multicenter study to assess symptoms and satisfaction with treatment. Patients were evaluated with the Douleur Neuropathique en 4 questions (DN4), the Brief Pain Inventory (BPI) and the Treatment Satisfaction for Medication Questionnaire (SATMED-Q) overall satisfaction domain.

Results

1,670 patients (mean age 58 years, 59 % women), previously untreated or treated with ≥1 drug other than pregabalin, were treated with pregabalin (37 % on monotherapy). At 3 months, pain intensity and its interference with activities decreased by half (p < 0.0001), while the number of days with no or mild pain increased by a mean of 4.5 days (p < 0.0001). Treatment satisfaction increased twofold (p < 0.0001). Patients with a shorter history of pain and those with neuralgia and peripheral nerve compression syndrome (PCS) as etiologies had the highest proportion on monotherapy and showed the greatest improvements in pain-related parameters in their respective group categories.

Conclusion

Treatment with pregabalin (as monotherapy or combination therapy) provides benefits in pain and treatment satisfaction in patients with NP, including refractory cases. Shorter disease progression and neuralgia and PCS etiologies are favorable factors for pregabalin treatment response.

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.

Pregabalin: latest safety evidence and clinical implications for the management of neuropathic pain

Used mainly for the management of neuropathic pain, pregabalin is a gabapentinoid or anticonvulsant that was initially developed as an antiepileptic agent. After more than a decade of experience with pregabalin, experience and studies have shown that the adverse effect profile of pregabalin is well tolerated for the management of neuropathic pain and other conditions. Its use is associated with benign central nervous system and systemic adverse effects, and there are very limited metabolic, idiosyncratic or known teratogenic adverse effects. Along with its efficacy in particular neuropathic pain conditions, pregabalin's safety led it to be one of the first pharmacotherapies considered for the management of neuropathic pain. This review discusses the use of pregabalin as well as its potential adverse effects, including the most commonly noted features of sedation, dizziness, peripheral edema and dry mouth. Although other adverse effects may occur, these appear to be uncommon. The review also discusses the clinical implications of pregabalin's use for the clinician.

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.

Economic impact of a triptan Rx-to-OTC switch in six EU countries

INTRODUCTION

Triptans have been safely and effectively used in the management of migraine for more than fifteen years, and it seems reasonable to wonder what would be the economic impact of moving a specific triptan to OTC availability. The objective of this study was then to examine the economic impact of payer policies of a triptan Rx-to-OTC switch in six EU countries (France, UK, Spain, Italy, Germany and Poland).

METHODS

A decision model was used to model the budgetary impact of a triptan Rx-to-OTC switch from the third-party payer (TPP) and the societal perspectives, using a one-year timeframe.

RESULTS

From the TPP perspective, it is estimated that the current overall direct spending on the management of migraine attacks across the 6 EU Member States is €582 million annually, and that the savings would reach €75 million (13% of the overall direct economic burden of migraine). From the societal perspective, €86 million annually would be added.

CONCLUSIONS

Given evidence of effectiveness and safety, and given the potential savings, a triptan Rx-to-OTC switch is a reasonable public policy decision.

Antinociceptive effect of matrine on vincristine-induced neuropathic pain model in mice

Chemotherapy drugs treatment causes neuropathic pain, hyperalgesia and allodynia are common components of neuropathic pain, so effectively therapeutic strategy is required. In this study, we evaluated the antinociceptive effects of matrine on vincristine-induced neuropathic pain in mice. Vincristine (100 μg/kg i.p.) was administered once per day for 7 days (day 0-6) in mice. Matrine (15, 30, 60 mg/kg, i.p.) was repeated administration in early phase (day 0-6) or late phase (day 7-13). Hyperalgesia and allodynia were evaluated by withdrawal response using von Frey filaments, plantar and cold-plate on 7, 14 and 21 day. Injection of vincristine produced mechanical hyperalgesia and cold allodynia. Matrine was found to produce a protective role in both von Frey filaments and cold-plate test. The analysis of the effect supports the hypothesis that matrine is useful in therapy of vincristine-induced neuropathic pain. In conclusion, this study demonstrates that administration of matrine is associated with antinociceptive effect on mechanical and cold stimuli in a mice model of vincristine-induced neuropathy pain.

Cost savings associated with early initiation of pregabalin in the management of peripheral neuropathic pain

OBJECTIVE

Peripheral neuropathic pain (PNP) is associated with significant economic burden. Guidelines recommend the early adoption of appropriate pharmacological interventions. The aim of this study was to explore whether early initiation of pregabalin was associated with lower economic burden, than later initiation, in the management of refractory chronic PNP.

METHODS

A secondary analysis of a multicenter, observational cost-of-illness study was carried out in adults older than 18 years of age with refractory chronic PNP. Patients were pregabalin naive, with a poor response to previous analgesic therapy, defined as pain >40 in a 0 to 100 mm visual analog scale after, at least, 1 analgesic. The total costs, health care and indirect, assessed 12 weeks before the initiation of pregabalin were analyzed according to the time elapsed since diagnosis.

RESULTS

One thousand one hundred thirty-nine outpatients, 59.3 (12.8) years old, 59.3% women, 2.0 (3.5) years with a diagnosis of PNP, fulfilled the criteria for analysis. Adjusted (pain intensity, sex, age, and body mass index) mean total costs 12 weeks before the baseline visit were significantly lower when pregabalin was initiated early (<6 mo; n=389) in comparison with later initiation; 6 to 12 months (n=328), or >12 months (n=422) after diagnosis; €2439 (2197; 2681) versus €3011 (2758; 3264) and €2945 (2717; 3173), respectively (P<0.01 in both cases). Lower health care costs and fewer lost-workday equivalents with early initiation of pregabalin were the main factors contributing to these findings.

DISCUSSION

Early initiation of pregabalin treatment after diagnosis in patients with refractory chronic PNP may result in substantial cost savings from a societal perspective in daily practice in Spain.

Platelet-rich plasma and the elimination of neuropathic pain

Peripheral neuropathic pain typically results from trauma-induced nociceptive neuron hyperexcitability and their spontaneous ectopic activity. This pain persists until the trauma-induced cascade of events runs its full course, which results in complete tissue repair, including the nociceptive neurons recovering their normal biophysical properties, ceasing to be hyperexcitable, and stopping having spontaneous electrical activity. However, if a wound undergoes no, insufficient, or too much inflammation, or if a wound becomes stuck in an inflammatory state, chronic neuropathic pain persists. Although various drugs and techniques provide temporary relief from chronic neuropathic pain, many have serious side effects, are not effective, none promotes the completion of the wound healing process, and none provides permanent pain relief. This paper examines the hypothesis that chronic neuropathic pain can be permanently eliminated by applying platelet-rich plasma to the site at which the pain originates, thereby triggering the complete cascade of events involved in normal wound repair. Many published papers claim that the clinical application of platelet-rich plasma to painful sites, such as muscle injuries and joints, or to the ends of nerves evoking chronic neuropathic pain, a process often referred to as prolotherapy, eliminates pain initiated at such sites. However, there is no published explanation of a possible mechanism/s by which platelet-rich plasma may accomplish this effect. This paper discusses the normal physiological cascade of trauma-induced events that lead to chronic neuropathic pain and its eventual elimination, techniques being studied to reduce or eliminate neuropathic pain, and how the application of platelet-rich plasma may lead to the permanent elimination of neuropathic pain. It concludes that platelet-rich plasma eliminates neuropathic pain primarily by platelet- and stem cell-released factors initiating the complex cascade of wound healing events, starting with the induction of enhanced inflammation and its complete resolution, followed by all the subsequent steps of tissue remodeling, wound repair and axon regeneration that result in the elimination of neuropathic pain, and also by some of these same factors acting directly on neurons to promote axon regeneration thereby eliminating neuropathic pain.

Pregabalin versus gabapentin in the management of peripheral neuropathic pain associated with post-herpetic neuralgia and diabetic neuropathy: a cost effectiveness analysis for the Greek healthcare setting

BACKGROUND

The anticonvulsants pregabalin and gabapentin are both indicated for the treatment of peripheral neuropathic pain. The decision on which treatment provides the best alternative, should take into account all aspects of costs and outcomes associated with the two therapeutic options. The objective of this study was to examine the cost - effectiveness of the two agents in the management of patients with painful diabetic neuropathy or post - herpetic neuralgia, under the third party payer perspective in Greece.

METHODS

The analysis was based on a dynamic simulation model which estimated and compared the costs and outcomes of pregabalin and gabapentin in a hypothetical cohort of 1,000 patients suffering from painful Diabetic Peripheral Neuropathy (DPN) or Post-Herpetic Neuralgia (PHN). In the model, each patient was randomly allocated an average pretreatment pain score, measured using an eleven-point visual analogue scale (0 - 10) and was "run through" the model, simulating their daily pain intensity and allowing for stochastic calculation of outcomes, taking into account medical interventions and the effectiveness of each treatment.

RESULTS

Pregabalin demonstrated a reduction in days with moderate to severe pain when compared to gabapentin. During the 12 weeks the pregabalin arm demonstrated a 0.1178 (SE 0.0002) QALY gain, which proved to be 0.0063 (SE 0.0003) higher than that in the gabapentin arm. The mean medication cost per patient was higher for the pregabalin arm when compared to the gabapentin arm (i.e. €134.40) over the 12 week treatment period. However, this higher cost was partially offset by the reduced direct medical costs (i.e. the cost of specialist visits, the cost of diagnostic tests and the other applied interventions). Comparing costs with respective outcomes, the ICERs for pregabalin versus gabapentin were €13 (95%CI: 8 - 18) per additional day with no or mild pain and €19,320 (95%CI: 11,743 - 26,755) per QALY gained.

CONCLUSIONS

Neuropathic pain carries a great disease burden for patients and society and, is also, associated with a significant economic burden. The treatment of pain associated with DPN and PHN with pregabalin is a cost-effective intervention for the social security in Greece compared to gabapentin. Thus, these findings need to be taken into consideration in the decision - making process when considering which therapy to use for the treatment of neuropathic pain.

Cost analysis of adding pregabalin or gabapentin to the management of community-treated patients with peripheral neuropathic pain

OBJECTIVE

To compare the cost of adding either pregabalin or gabapentin to the management of community-treated patients with peripheral neuropathic pain (PNP).

METHODS

A retrospective observational study was conducted using medical records from a Spanish health care provider claims database. Patients receiving health care for PNP, above 18 years and for which either pregabalin or gabapentin was initiated between 2006 and 2008 were included. Economic evaluation included health care resource utilization costs and costs due to sick leave.

RESULTS

A total of 1163 patients with PNP were eligible for analysis: 764 were prescribed pregabalin and 399 gabapentin in addition to current pain therapy. Mean age was 59.2 years and 62.2% were female. Concomitant use of analgesics was higher in the gabapentin cohort (3.2 vs. 2.7; P = 0.003), mainly due to non-steroidal anti-inflammatory drugs (74.9% vs. 69.5%; P = 0.018) and opioids (27.7% vs. 17.9%; P = 0.031). Adjusted total costs per patient was lower in pregabalin-treated patients (€2514 vs. €3241; P = 0.003), due to less sick leave (€1067 vs. €1633; P = 0.018) and lower health care costs (€1447 vs. €1609; P = 0.004). The higher acquisition cost of pregabalin (€351 vs. €191; P < 0.001) was largely compensated with lower costs in medical visits, physiotherapy, hospital stays and concomitant analgesics.

CONCLUSIONS

In community-treated patients with PNP, total costs were considerably less for those patients initiated with pregabalin therapy than for those patients starting gabapentin add-on therapy. The relatively higher treatment acquisition cost of pregabalin was largely compensated by the overall lower costs for the other components of health care resources and sick leave, thus reducing the economic impact on the health care provider's budget and society.

A clinical study to compare the efficacy and safety of pregabalin sustained release formulation with pregabalin immediate release formulation in patients of diabetic peripheral neuropathic pain

OBJECTIVE

To compare the efficacy and safety of sustained release (SR) formulation of pregabalin with immediate release (IR) formulation in patient with diabetic peripheral neuropathic pain.

MATERIALS AND METHODS

In this open label, randomized, comparative, multicentric study, the primary efficacy measure was reduction in visual analogue scale (VAS) of short form McGill pain questionnaire (SF-MPQ) score from baseline to last visit. The secondary evaluation measures included reduction in SF-MPQ descriptive score and present pain intensity score and change in clinical global impression - improvement of illness (CGI-I) and clinical global impression - severity of illness (CGI-S) from baseline to last visit. Total duration of the study was 12 weeks. Safety evaluation was done by recording treatment emergent adverse events and laboratory investigations at baseline and end of treatment.

RESULTS

Of 265 randomized patients, 133 received pregabalin SR tablets and 132 pregabalin IR. Patients randomized to both treatments responded to respective treatments. The least square means of VAS score in both the groups were reduced significantly (P <0.01). Reduction in both groups was similar (P = ns). At the end of the trial in both the groups, there was a significant reduction in the SF-MPQ descriptive score (P <0.01), severity of illness as well as clinically significant improvement in the symptoms. Difference between the groups for CGI-I (P = 0.37) and CGI-S (P = 0.41) score was not statistically significant. Treatment in both the groups was found safe and well tolerated.

CONCLUSION

The study shows that the pregabalin SR is safe and effective in patients of diabetic peripheral neuropathic pain. The results of the study demonstrated that pregabalin SR has comparable efficacy and safety as pregabalin IR.

Behavioral testing in rodent models of orofacial neuropathic and inflammatory pain

Orofacial pain conditions are often very debilitating to the patient and difficult to treat. While clinical interest is high, the proportion of studies performed in the orofacial region in laboratory animals is relatively low, compared with other body regions. This is partly due to difficulties in testing freely moving animals and therefore lack of reliable testing methods. Here we present a comprehensive review of the currently used rodent models of inflammatory and neuropathic pain adapted to the orofacial areas, taking into account the difficulties and drawbacks of the existing approaches. We examine the available testing methods and procedures used for assessing the behavioral responses in the face in both mice and rats and provide a summary of some pharmacological agents used in these paradigms to date. The use of these agents in animal models is also compared with outcomes observed in the clinic.

Peripheral neuropathy: evidence-based treatment of a complex disorder

Peripheral neuropathy (PN) is a common and often progressive condition frequently seen in primary care. The chronic pain associated with PN, or neuropathic pain, can significantly diminish patients' quality of life and be challenging to treat.

Pharmacological versus microvascular decompression approaches for the treatment of trigeminal neuralgia: clinical outcomes and direct costs

In idiopathic trigeminal neuralgia (TN) the neuroimaging evaluation is usually normal, but in some cases a vascular compression of trigeminal nerve root is present. Although the latter condition may be referred to surgery, drug therapy is usually the first approach to control pain. This study compared the clinical outcome and direct costs of (1) a traditional treatment (carbamazepine [CBZ] in monotherapy [CBZ protocol]), (2) the association of gabapentin (GBP) and analgesic block of trigger-points with ropivacaine (ROP) (GBP+ROP protocol), and (3) a common TN surgery, microvascular decompression of the trigeminal nerve (MVD protocol). Sixty-two TN patients were randomly treated during 4 weeks (CBZ [n = 23] and GBP+ROP [n = 17] protocols) from cases of idiopathic TN, or selected for MVD surgery (n = 22) due to intractable pain. Direct medical cost estimates were determined by the price of drugs in 2008 and the hospital costs. Pain was evaluated using the Numerical Rating Scale (NRS) and number of pain crises; the Hospital Anxiety and Depression Scale, Sickness Impact Profile, and satisfaction with treatment and hospital team were evaluated. Assessments were performed at day 0 and 6 months after the beginning of treatment. All protocols showed a clinical improvement of pain control at month 6. The GBP+ROP protocol was the least expensive treatment, whereas surgery was the most expensive. With time, however, GBP+ROP tended to be the most and MVD the least expensive. No sequelae resulted in any patient after drug therapies, while after MDV surgery several patients showed important side effects. Data reinforce that, (1) TN patients should be carefully evaluated before choosing therapy for pain control, (2) different pharmacological approaches are available to initiate pain control at low costs, and (3) criteria for surgical interventions should be clearly defined due to important side effects, with the initial higher costs being strongly reduced with time.