Low-dose doxepin: in the treatment of insomnia.

Doxepin binds with high specificity and affinity to the histamine H(1) receptor compared with other receptors. Therefore, at low doses, doxepin selectively antagonises H(1) receptors, which is believed to promote the initiation and maintenance of sleep. In three large, well designed, phase III trials in adult or elderly patients with chronic primary insomnia, oral, low-dose doxepin 3 or 6 mg once daily improved wake time after sleep onset, total sleep time and sleep efficiency to a significantly greater extent than placebo. Significant between-group differences in polysomnographic sleep recordings that favoured low-dose doxepin were evident after a single administration of the drug. Other efficacy measures, including patient-reported sleep quality, also favoured low-dose doxepin over placebo. Symptom control was maintained for up to 12 weeks of low-dose doxepin administration and there was no evidence of physical dependence or worsening insomnia after doxepin withdrawal. Oral, low-dose doxepin 6 mg was also significantly more effective than placebo in a large, well designed trial modelling transient insomnia in healthy adults, according to polysomnographic recordings (e.g. in latency to persistent sleep). Oral, low-dose doxepin was generally well tolerated in clinical trials.

Etoricoxib: a review of its use in the symptomatic treatment of osteoarthritis, rheumatoid arthritis, ankylosing spondylitis and acute gouty arthritis.

Etoricoxib is a selective cyclo-oxygenase (COX)-2 inhibitor, approved in Europe for the symptomatic treatment of osteoarthritis, rheumatoid arthritis, ankylosing spondylitis and acute gouty arthritis. Etoricoxib provided similar symptomatic relief to nonselective NSAIDs in patients with these conditions, and to celecoxib in patients with osteoarthritis. The drug was associated with fewer uncomplicated upper gastrointestinal (GI) adverse events than nonselective NSAIDs, and was noninferior to diclofenac in terms of the rate of thrombotic cardiovascular (CV) events. Etoricoxib may be considered as a treatment option for patients requiring NSAID therapy, particularly those at risk of upper GI events, after careful consideration of significant risk factors for CV events (including uncontrolled hypertension). As with all NSAIDs, the potential GI and CV risks of treatment with etoricoxib should be weighed against the potential benefits in individual patients, and it should be administered at the lowest effective dose for as short a duration as possible.

Lisdexamfetamine dimesylate: in attention-deficit hyperactivity disorder in adults.

Lisdexamfetamine dimesylate is a long-acting amfetamine prodrug that requires in vivo hydrolysis to gradually release active d-amfetamine. It is approved in the US for the treatment of attention-deficit hyperactivity disorder (ADHD) in adults and in children aged 6-12 years. In a study in adult stimulant abusers, oral lisdexamfetamine 50 or 100 mg showed less 'likability' response than immediate-release d-amfetamine 40 mg on the Drug Rating Questionnaire-Subject (DRQS) Liking scale. However, there was no significant difference between lisdexamfetamine 150 mg and d-amfetamine 40 mg. In a randomized, double-blind, phase III trial in adult patients with ADHD, oral lisdexamfetamine 30, 50 or 70 mg/day for 4 weeks caused a significantly greater improvement in ADHD-Rating Scale (ADHD-RS) total score than placebo; significant between-group differences favouring lisdexamfetamine were evident after 1 week. Lisdexamfetamine was generally well tolerated in adult patients with ADHD, with most treatment-emergent adverse events being of mild to moderate severity and consistent with the known effects of psychostimulants.

Pregabalin: a review of its use in fibromyalgia.

Oral pregabalin, a calcium channel alpha(2)delta-subunit ligand with analgesic, anxiolytic and antiepileptic activity, has shown efficacy in the treatment of fibromyalgia. It has a multidimensional effect in the treatment of this complex condition, and is associated with rapid and clinically significant improvements in several outcome measures relating to core symptoms of the syndrome, including pain and sleep, in patients with long-standing fibromyalgia. Pregabalin treatment is also associated with improvements in the overall health status of these patients. The beneficial effects of pregabalin are durable in patients with an initial response to the drug. The most common adverse events associated with the drug are dizziness and somnolence, which are generally mild to moderate in intensity and are tolerated by many patients. Pregabalin is, therefore, a valuable option in the first-line treatment of patients with fibromyalgia.

Amlodipine/atorvastatin fixed-dose combination: a review of its use in the prevention of cardiovascular disease and in the treatment of hypertension and dyslipidemia.

Amlodipine/atorvastatin (Caduet) is a once-daily fixed-dose combination of the dihydropyridine calcium channel antagonist amlodipine and the HMG-CoA reductase inhibitor atorvastatin. In Europe, the combination is indicated for the prevention of cardiovascular events in hypertensive patients with three concomitant cardiovascular risk factors and, in the US, it is indicated for the management of hypertension and dyslipidemia in patients for whom treatment with both agents is appropriate. In clinical trials, the fixed-dose combination of amlodipine/atorvastatin effectively managed two important risk factors simultaneously in hypertensive patients at risk of cardiovascular disease or in those with concomitant hypertension and dyslipidemia. The combination is bioequivalent to amlodipine and atorvastatin given alone and does not modify the efficacy of either single agent. Amlodipine/atorvastatin is generally well tolerated, with a tolerability profile consistent with that of each single agent. Compared with the coadministration of each single agent, the convenience of single-pill amlodipine/atorvastatin has the potential to improve patient adherence and the management of cardiovascular risk in selected patients, thereby improving clinical outcomes.

Pramipexole: in restless legs syndrome.

Pramipexole is an oral, non-ergoline dopamine agonist with selectivity for the dopamine D(3) receptor, which was recently approved in the EU and the US for the treatment of idiopathic restless legs syndrome (RLS) in adults. In a polysomnographic study, pramipexole 0.125, 0.25, 0.50 or 0.75 mg once daily for 3 weeks significantly reduced from baseline the periodic limb movement index compared with placebo (-27 to -53 vs -3). Pramipexole at a median dosage of 0.35 mg/day for 6 weeks significantly reduced from baseline the mean International RLS Study Group rating scale (IRLS) score compared with placebo (-12.4 vs -6.1) and produced a significantly higher response ('much improved' or 'very much improved') rate (63% vs 33%) according to the Clinical Global Impressions-Improvement (CGI-I) scale. In a controlled-withdrawal study in which responders to pramipexole following 6 months' therapy were randomised to pramipexole or placebo for 12 weeks, significantly less pramipexole than placebo recipients reached the target event of predefined worsening of symptoms (21% vs 86%). Treatment with pramipexole 0.25, 0.50 or 0.75 mg once daily for 12 weeks significantly reduced IRLS scores from baseline values (-13 to -14 vs -9) and produced significantly higher proportions of CGI-I responders (68-75% vs 51%) compared with placebo. Pramipexole was generally well tolerated, with most adverse events being transient and of mild to moderate severity.

The efficacy and tolerability of newer biologics in rheumatoid arthritis: best current evidence.

(1) Biologics have had a tremendous impact on the management of rheumatoid arthritis.(2) Three new biologics have been approved or filed for approval for the treatment of rheumatoid arthritis in the last 2 years: abatacept, rituximab, and tocilizumab.(3) The utility of the newer biologics against the background of existing, well established biologics (infliximab, etanercept, adalimumab, and anakinra) has not been evaluated systematically.

Imatinib: a review of its use in the management of gastrointestinal stromal tumours.

Imatinib (Gleevec, Glivec is a small molecule inhibitor of tyrosine kinase that has been evaluated for efficacy in patients with gastrointestinal stromal tumours (GIST). The drug is approved for the treatment of unresectable and/or metastatic, KIT-positive GIST in the US, Europe and many other countries. Imatinib has had a significant impact on the management of advanced GIST, which has traditionally had a poor prognosis, and has quickly become the first choice of treatment in the medical therapy of unresectable and/or metastatic, KIT-positive GIST. In randomised, nonblind trials, imatinib 400-800 mg/day produced complete or partial responses in up to two-thirds of patients, with long-term efficacy, and substantially prolonged progression-free and overall survival. The drug was generally well tolerated in GIST patients, including during long-term treatment. Imatinib dosages higher than 400 mg/day (up to 800 mg/day) may improve progression-free survival, with an increase in dosage benefiting some patients who show disease progression at the lower dosage, particularly in those with exon 9 mutation; however, there is also a dose-related increase in imatinib toxicity. Mutational genotype and other, non-biomolecular factors may aid in guiding imatinib therapy and predicting prognosis in GIST patients. Further data are required to evaluate the use of imatinib in adjuvant and neoadjuvant settings. Nevertheless, imatinib currently provides the most effective treatment option in the management of advanced GIST.

Imatinib: a review of its use in chronic myeloid leukaemia.

Imatinib (Gleevec, Glivec) is a synthetic tyrosine kinase inhibitor used in the treatment of chronic myeloid leukaemia (CML). It is specifically designed to inhibit the breakpoint cluster region (BCR)-Abelson (ABL) fusion protein that results from the chromosomal abnormality known as the Philadelphia chromosome. CML is characterised by this abnormality, which leads to abnormalities of the peripheral blood and bone marrow including an increase in the number of granular leukocytes. Imatinib is approved in numerous countries worldwide for the treatment of newly diagnosed Philadelphia chromosome-positive (Ph+) chronic-phase CML, Ph+ accelerated-phase or blast-crisis CML, and in patients with Ph+ chronic-phase CML who have failed to respond to interferon-alpha therapy. It is also indicated in paediatric patients with newly diagnosed Ph+ chronic-phase CML, in accelerated-phase or blast-crisis CML, or in chronic-phase CML after failure of interferon-alpha therapy or when the disease has recurred after haematopoietic stem cell transplantation (HSCT). Approved indications, however, may vary by country. Imatinib is effective and generally well tolerated in patients with Ph+ CML. In patients with newly diagnosed chronic-phase CML, imatinib was more effective than interferon-alpha plus cytarabine in preventing progression of the disease and in achieving haematological and cytogenetic responses. Overall survival rates remain high after 5 years of follow-up, and historical comparisons with other treatments demonstrate improved overall survival with imatinib in the long term. Patients with accelerated-phase or blast-crisis CML, or those who have not responded to prior interferon-alpha therapy also benefit from imatinib treatment. Some patients become resistant or intolerant to imatinib therapy; management strategies to overcome these problems include dosage adjustment, other treatments, or combination therapy with imatinib and other agents. Allogeneic HSCT is currently the only potentially curative treatment, but it is associated with high rates of morbidity and mortality and is not suitable for all patients. The introduction of imatinib has had a marked impact on outcomes in patients with CML. It remains a valuable treatment for all stages of the disease, especially initial treatment of newly diagnosed Ph+ chronic-phase CML, and is endorsed by European and US treatment guidelines as a first-line option.

Spotlight on reteplase in thrombotic occlusive disorders.

Reteplase (Retavase) is a plasminogen activator, mimicking endogenous tissue plasminogen activator (t-PA), a serine protease, converting plasminogen to plasmin and thereby precipitating thrombolysis. It is a third-generation recombinant form of t-PA that operates in the presence of fibrin (i.e. it is fibrin specific). Reteplase can be administered as a bolus dose (nonweight-based), rather than an infusion, which promotes rapid and safe administration. The ease of administration of this reteplase dosage regimen (two 10U bolus doses, each over 2 minutes, 30 minutes apart) is conducive to prehospital initiation of thrombolytic treatment in patients with ST-segment elevation myocardial infarction (STEMI), which reduces the time to treatment, a critical factor in improving long-term survival. In large randomized clinical trials of patients with STEMI, reteplase was superior to alteplase for coronary artery patency (according to TIMI [thrombolysis in myocardial infarction] flow) at 60 and 90 minutes, but there was no significant difference between agents for mortality rate and incidence of intracranial bleeding. The 35-day mortality rates were equivalent for reteplase and streptokinase recipients; there was reduced incidence of some cardiac events with reteplase versus streptokinase, but a greater incidence of hemorrhagic stroke. Reteplase has also shown thrombolytic efficacy (in nonapproved indications) as a catheter-directed intra-arterial or intravenous infusion for peripheral vessel occlusions, as 5-minute bolus doses (in 1U increments) for acute ischemic stroke, as a low-dose solution for occluded catheters or grafts, and as an intravenous double bolus for massive pulmonary embolism. Across studies in these indications, the incidence of bleeding complications associated with reteplase treatment appeared to be similar to that associated with other fibrin-specific thrombolytic agents. With its efficacy, and the ease of administration of the bolus doses potentially minimizing dosage errors when treatment is administered under time pressure, reteplase is a valuable option for pre- or in-hospital thrombolytic treatment in patients with STEMI, and is a useful thrombolytic for the treatment of the other thrombotic occlusive disorders described.

Spotlight on ranolazine in chronic stable angina pectoris.

Ranolazine (Ranexa), a piperazine derivative, is a new antianginal agent approved for the treatment of chronic stable angina pectoris for use as combination therapy when angina is not adequately controlled with other antianginal agents. While the exact mechanism of action of ranolazine is not known, its antianginal and anti-ischemic effects do not appear to depend upon changes in BP or heart rate. An extended-release (ER) oral formulation of ranolazine has been developed to facilitate twice-daily administration whilst maintaining therapeutically effective plasma concentrations. In patients with chronic stable angina, ranolazine ER monotherapy was shown to improve exercise duration at trough plasma drug concentration in a dose-dependent manner compared with placebo. The drug was effective as adjunctive therapy in patients with chronic stable angina whose condition was not controlled adequately with conventional antianginal therapy. In randomized clinical trials, ranolazine ER was well tolerated, with no overt effects on cardiovascular hemodynamics or conduction, apart from a modest increase in corrected QT interval (but no torsades de pointes). Importantly, the efficacy and tolerability of ranolazine ER were not affected by old age and co-morbid conditions (heart failure or diabetes mellitus). Comparative trials of ranolazine ER with other antianginal agents and trials examining its effects on long-term morbidity and mortality in patients with ischemic heart disease are required to determine with greater certainty the place of the drug in current antianginal therapy. Nevertheless, ranolazine ER may well prove to be a useful alternative and adjunct to conventional hemodynamic antianginal therapy in the treatment of chronic stable angina.

Spotlight on darbepoetin alfa in the treatment of anemia in patients with cancer receiving chemotherapy.

Darbepoetin alfa (Aranesp) is an analog of recombinant human erythropoietin (rHuEPO) produced using recombinant DNA technology. The high number of sialic acid moieties in darbepoetin alfa results in a prolonged half-life and enhanced in vivo biologic activity compared with rHuEPO (as demonstrated in animal studies), and permits a reduction in the frequency of administration. Subcutaneous darbepoetin alfa 2.25 microg/kg once weekly or 500microg once every 3 weeks (with a provision for dosage adjustments) is an effective and well tolerated erythropoietic agent in anemic patients with cancer receiving chemotherapy. In randomized, controlled clinical trials, the drug increased hemoglobin levels and reduced the need for blood transfusions in patients with various types of nonmyeloid malignancies, and also ameliorated anemia-related fatigue, thereby improving their health-related quality of life scores. The once-every-3-weeks dosage regimen provides further convenience by offering the possibility of synchronizing its administration with most chemotherapy regimens. Direct comparisons between approved dosages of darbepoetin alfa and other erythropoietic agents have not been conducted. Such comparisons would be very helpful in formulating definitive conclusions about their relative efficacy and cost effectiveness. Darbepoetin alfa provides an effective and well tolerated treatment option for the treatment of anemia in patients with cancer receiving chemotherapy.

Varenicline: a review of its use as an aid to smoking cessation therapy.

Varenicline is an orally administered alpha4beta2 nicotinic acetylcholine (ACh) receptor partial agonist. It has been approved by the US FDA (Chantix) and the European Commission (Champix) for use as an aid to smoking cessation therapy. Varenicline is an effective and generally well tolerated treatment for use in smokers who want to quit. In two well designed, phase III trials, 12 weeks' treatment with varenicline was associated with significantly higher continuous abstinence rates at weeks 9-12 than placebo or bupropion sustained-release (SR). In the longer term, continuous abstinence rates for weeks 9 through 52 demonstrated that the odds of remaining abstinent were 2.7 to 3.1 times higher with 12 weeks of varenicline treatment than with placebo; the significant difference between varenicline and bupropion SR was also maintained in the longer term in one trial. Moreover, varenicline appeared to attenuate the urge to smoke, negative affect withdrawal symptoms and the reinforcing effects of smoking. Among those achieving abstinence, an additional 12 weeks of varenicline therapy helped increase the likelihood of long-term abstinence. Thus, varenicline is a valuable new agent for use as an aid to smoking cessation treatment.

Rivastigmine: in Parkinson's disease dementia.

Rivastigmine is a carbamate-type dual inhibitor of brain acetyl- and butyrylcholinesterases that has been evaluated in the symptomatic treatment of patients with mild to moderate dementia associated with idiopathic Parkinson's disease. Oral rivastigmine 3-12 mg/day for 24 weeks was significantly more effective than placebo in ameliorating cognitive and functional decline, including attentional deficits, in patients with Parkinson's disease dementia in a randomised, double-blind trial. The beneficial effects of rivastigmine observed in the double-blind trial were generally maintained in a 24-week extension of this study in which all patients received active treatment; placebo recipients who switched to rivastigmine also experienced improvements in their cognitive and functional symptoms at week 48. Rivastigmine appeared to be generally well tolerated, with the most common adverse events being mild to moderate in intensity and cholinergic in nature. Parkinsonian symptoms (mainly tremor) were more common in rivastigmine than placebo recipients.

Reteplase: a review of its use in the management of thrombotic occlusive disorders.

Reteplase (Retavase) is a plasminogen activator, mimicking endogenous tissue plasminogen activator (t-PA), a serine protease, converting plasminogen to plasmin and thereby precipitating thrombolysis. It is a third-generation recombinant form of t-PA that operates in the presence of fibrin (i.e. it is fibrin specific). Reteplase can be administered as a bolus dose (nonweight-based) rather than an infusion, which promotes rapid and safe administration. The ease of administration of this reteplase dosage regimen (two 10U bolus doses, each over 2 minutes, 30 minutes apart) is conducive to prehospital initiation of thrombolytic treatment in patients with ST-segment elevation myocardial infarction (STEMI), which reduces the time to treatment, a critical factor in improving long-term survival. In large randomized clinical trials of patients with STEMI, reteplase was superior to alteplase for coronary artery patency (according to TIMI [thrombolysis in myocardial infarction] flow) at 60 and 90 minutes, but there was no significant difference between agents for mortality rate and incidence of intracranial bleeding. The 35-day mortality rates were equivalent for reteplase and streptokinase recipients; there was reduced incidence of some cardiac events with reteplase versus streptokinase, but a greater incidence of hemorrhagic stroke. Reteplase has also shown thrombolytic efficacy (in nonapproved indications) as a catheter-directed intra-arterial or intravenous infusion for peripheral vessel occlusions, as 5-minute bolus doses (in 1U increments) for acute ischemic stroke, as a low-dose solution for occluded catheters or grafts, and as an intravenous double bolus for massive pulmonary embolism. Across studies in these indications, the incidence of bleeding complications associated with reteplase treatment appeared to be similar to that associated with other thrombolytic agents. With its efficacy, and the ease of administration of the bolus doses potentially minimizing dosage errors when treatment is administered under time pressure, reteplase is a valuable option for pre- or in-hospital thrombolytic treatment in patients with STEMI, and is a useful thrombolytic for the treatment of the other thrombotic occlusive disorders described.

Human papillomavirus quadrivalent (types 6, 11, 16, 18) recombinant vaccine (Gardasil).

Human papillomavirus (HPV) quadrivalent recombinant vaccine is a mixture of virus-like particles derived from the L1 capsid proteins of HPV types 6, 11, 16 and 18. It is administered intramuscularly in a three-dose regimen, with the initial injection followed by subsequent doses at months 2 and 6. The vaccine is indicated for use in the prevention of cervical cancer, vulvar and vaginal precancer and cancers, precancerous lesions and genital warts associated with HPV types 6, 11, 16 or 18 infection in adolescents and young women. The quadrivalent vaccine has demonstrated good immunogenicity in young women (16-26 years) and male and female adolescents (aged 9-15 years), inducing high and persistent anti-HPV antibody titres. In a randomised phase III trial designed to bridge efficacy in young women to adolescents (using immunogenicity as a surrogate), the quadrivalent HPV vaccine in adolescents was at least as immunogenic as that in young women. In randomised, double-blind, placebo-controlled trials in >20 000 young women (aged 16-26 years), the vaccine was highly effective in preventing cervical dysplasia of any grade and external genital lesions related to HPV types 6, 11, 16 and 18 infection. These women were followed up for an average of 2 years.black triangle The vaccine was well tolerated, with injection-site reactions and fever being the most common vaccine-related adverse events.

Darbepoetin alfa: a review of its use in the treatment of anaemia in patients with cancer receiving chemotherapy.

Darbepoetin alfa (Aranesp) is an analogue of recombinant human erythropoietin (rHuEPO) produced using recombinant DNA technology. The high number of sialic acid moieties in darbepoetin alfa results in a prolonged half-life and enhanced in vivo biological activity compared with rHuEPO (as demonstrated in animal studies) and permits a reduction in the frequency of administration. Subcutaneous darbepoetin alfa 2.25 microg/kg once weekly or 500 microg once every 3 weeks (with a provision for dose adjustments) is an effective and well tolerated erythropoietic agent in anaemic patients with cancer receiving chemotherapy. In randomised, controlled clinical trials, the drug increased haemoglobin levels and reduced the need for blood transfusions in patients with various types of nonmyeloid malignancies and also ameliorated anaemia-related fatigue, thereby improving their health-related quality of life (HR-QOL) scores. The once-every-3-weeks dosage regimen provides further convenience by offering the possibility of synchronising its administration with most chemotherapy regimens. Direct comparisons between approved dosages of darbepoetin alfa and other erythropoietic agents have not been conducted. Such comparisons would be very helpful in formulating definitive conclusions about their relative efficacy and cost effectiveness. Darbepoetin alfa provides an effective and well tolerated treatment option for the treatment of anaemia in patients with cancer receiving chemotherapy.

Lubiprostone.

Lubiprostone (Amitiza) is an oral bicyclic fatty acid that selectively activates type 2 chloride channels in the apical membrane of the gastrointestinal epithelium, resulting in increased fluid secretion. In two pivotal, randomised, double-blind, multicentre phase III studies in patients with chronic idiopathic constipation, the frequency of spontaneous bowel movements (SBMs) was significantly greater in patients receiving lubiprostone 24microg twice daily than in those receiving placebo at each weekly timepoint throughout both 4-week studies (p < 0.05). At week 1 in one pivotal trial, the mean frequency of SBMs in the lubiprostone group was 5.9 per week compared with 4.0 per week in the placebo group (p < 0.0001) [baseline SBMs 1.3 and 1.5 per week]. Significantly greater improvements occurred with lubiprostone than placebo in the degree of straining, stool consistency and constipation severity (where reported) in both pivotal studies (p < 0.05 for all comparisons at all timepoints). Lubiprostone was generally well tolerated in clinical trials with no reports of treatment-related serious adverse events in pivotal trials. Nausea was the most common adverse event, occurring in up to 31% of patients receiving lubiprostone.