Comparative aspects of triptans in treating migraine

Subcutaneous sumatriptan delivery devices: comparative ease of use and preference among migraineurs

BACKGROUND

Several sumatriptan subcutaneous autoinjector devices for acute treatment of migraine patients are available, each device differs with respect to design and features. Determining device preference and ease of use is important because patients experiencing a migraine attack are often functionally impaired.

OBJECTIVE

The objective of this human factors study was to compare migraine patients' device use performance and preferences for three sumatriptan subcutaneous autoinjectors: a disposable two-step device (Zembrace^® SymTouch^®), a disposable three-step device (Sumavel^® DosePro^®), and a multistep reloadable device (Imitrex^® STATdose^®), using simulated injections.

METHODS

Each study subject performed two unaided simulated injections with each of three different drug delivery devices, which were presented in counterbalanced order. The participants were then asked to rate the three devices on various subjective measures. The primary end point was overall device preference using a visual analog scale.

RESULTS

A total of 54 subjects participated and each subject performed two simulated injections with each of the three devices. Most subjects preferred the two-step device (88.9%) to the three-step (13.0%) and the reloadable (1.9%). The two-step device had higher mean overall preference ratings (F (2, 159)=56.6, P<0.01) and higher ratings for ease of use, intuitiveness, convenience, portability, and control. The two-step device had a first injection full-dose delivery success rate of 44.4%, higher than both the reloadable (24.1%) and the three-step (3.7%) devices. The number of errors with the two-step device (n=3) was ~90% lower than the three-step (n=49) and reloadable (n=44) devices.

CONCLUSION

In this human factors study, 54 migraineurs used simulated injections to compare three sumatriptan subcutaneous delivery devices. Zembrace SymTouch, a two-step device, was most preferred compared with Sumavel DosePro and Imitrex STATdose. It also ranked highest for ease of use and various other measures. In this study, migraine patients preferred the autoinjector that they rated as simpler and more intuitive.

Human factors validation study of 3 mg sumatriptan autoinjector, for migraine patients

Background

Migraine pain relief is reported by more than 50% of patients who receive low dose (3 mg) of sumatriptan. Currently, there is no two-step autoinjector of low-dose sumatriptan available on the market for acute migraine treatment. To fulfill this need, a fully assembled, single-dose, subcutaneous autoinjector (sumatriptan 3 mg; product-code DFN-11) was developed. The device allows for injection with a simple two-step, push-to-inject process and provides feedback of the injection activation, progress, and completion.

Objective

To determine if DFN-11 autoinjector can be used correctly and safely by migraine patients.

Methods and participants

A human factors validation study was conducted with 45 migraine patients (30 oral-only medications users; 15 injectable sumatriptan users) who performed one unaided simulated injection. Two days prior, half the oral participants were briefly trained. All others were only given the device to inspect and written instructions to review. No injections were performed during the initial session. All participants received written instructions at the injection session.

Results

All participants (45/45; 100%) performed the injection without any errors. Objective measures included device removal from packaging, cap removal, expiration date check, inspection of fluid in window, identification of allowable injection site, proper device positioning, dose confirmation, and device disposal. All participants (45/45; 100%) reported no difficulty administering the injection and no concerns about using the autoinjector during a severe migraine onset.

Conclusion

The results showed that the DFN-11 autoinjector can be used with safe handling without patterns of confusion, failures, high-risk errors, wet injections, or patient safety risks. The DFN-11 autoinjector was validated to be used correctly and safely by migraine patients, whether they were injection experienced, unexperienced, trained, or self-trained.

Headache management: pharmacological approaches

Headache is one of the most common conditions presenting to the neurology clinic, yet a significant proportion of these patients are unsatisfied by their clinic experience. Headache can be extremely disabling; effective treatment is not only essential for patients but is rewarding for the physician. In this first of two parts review of headache, we provide an overview of headache management, emerging therapeutic strategies and an accessible interpretation of clinical guidelines to assist the busy neurologist.

Cost-effectiveness analysis of interventions for migraine in four low- and middle-income countries

BACKGROUND

Evidence of the cost and effects of interventions for reducing the global burden of migraine remains scarce. Our objective was to estimate the population-level cost-effectiveness of evidence-based migraine interventions and their contributions towards reducing current burden in low- and middle-income countries.

METHODS

Using a standard WHO approach to cost-effectiveness analysis (CHOICE), we modelled core set intervention strategies for migraine, taking account of coverage and efficacy as well as non-adherence. The setting was primary health care including pharmacies. We modelled 26 intervention strategies implemented during 10 years. These included first-line acute and prophylactic drugs, and the expected consequences of adding consumer-education and provider-training. Total population-level costs and effectiveness (healthy life years [HLY] gained) were combined to form average and incremental cost-effectiveness ratios. We executed runs of the model for the general populations of China, India, Russia and Zambia.

RESULTS

Of the strategies considered, acute treatment of attacks with acetylsalicylic acid (ASA) was by far the most cost-effective and generated a HLY for less than US$ 100. Adding educational actions increased annual costs by 1-2 US cents per capita of the population. Cost-effectiveness ratios then became slightly less favourable but still less than US$ 100 per HLY gained for ASA. An incremental cost of > US$ 10,000 would have to be paid per extra HLY by adding a triptan in a stepped-care treatment paradigm. For prophylaxis, amitriptyline was more cost-effective than propranolol or topiramate.

CONCLUSIONS

Self-management with simple analgesics was by far the most cost-effective strategy for migraine treatment in low- and middle-income countries and represents a highly efficient use of health resources. Consumer education and provider training are expected to accelerate progress towards desired levels of coverage and adherence, cost relatively little to implement, and can therefore be considered also economically attractive. Evidence-based interventions for migraine should have as much a claim on scarce health resources as those for other chronic, non-communicable conditions that impose a significant burden on societies.

Discovery of a potent, orally bioavailable and highly selective human neuronal nitric oxide synthase (nNOS) inhibitor, N-(1-(piperidin-4-yl)indolin-5-yl)thiophene-2-carboximidamide as a pre-clinical development candidate for the treatment of migraine

We recently reported a series of 1,6-disubstituted indoline-based thiophene amidine compounds (5) as selective neuronal nitric oxide synthase (nNOS) inhibitors to mitigate the cardiovascular liabilities associated with hERG K(+) channel inhibition (IC(50) = 4.7 μM) with previously reported tetrahydroquinoline-based selective nNOS inhibitors (4). The extended structure-activity relationship studies within the indoline core led to the identification of 43 as a selection candidate for further evaluations. The in vivo activity in two different pain (spinal nerve ligation and migraine pain) models, the excellent physicochemical and pharmacokinetic properties, oral bioavailability (F(po) = 91%), and the in vitro safety profile disclosed in this report make 43 an ideal candidate for further evaluation in clinical applications related to migraine pain.

Why pharmacokinetic differences among oral triptans have little clinical importance: a comment

Triptans, selective 5-HT1B/1D receptor agonists, are specific drugs for the acute treatment of migraine that have the same mechanism of action. Here, it is discussed why the differences among kinetic parameters of oral triptans have proved not to be very important in clinical practice. There are three main reasons: (1) the differences among the kinetic parameters of oral triptans are smaller than what appears from their average values; (2) there is a large inter-subject, gender-dependent, and intra-subject (outside/during the attack) variability of kinetic parameters related to the rate and extent of absorption, i.e., those which are considered as critical for the response; (3) no dose-concentration–response curves have been defined and it is, therefore, impossible both to compare the kinetics of triptans, and to verify the objective importance of kinetic differences; (4) the importance of kinetic differences is outweighed by non-kinetic factors of variability of response to triptans. If no oral formulations are found that can allow more predictable pharmacokinetics, the same problems will probably also arise with new classes of drugs for the acute treatment of migraine.

Practical considerations for the treatment of elderly patients with migraine

Treatment of migraine presents special problems in the elderly. Co-morbid diseases may prohibit the use of some medications. Moreover, even when these contraindications do not exist, older patients are more likely than younger ones to develop adverse events. Managing older migraine patients, therefore, necessitates particular caution, including taking into account possible pharmacological interactions associated with the greater use of drugs for concomitant diseases in the elderly. Paracetamol (acetaminophen) is the safest drug for symptomatic treatment of migraine in the elderly. Use of selective serotonin 5-HT(1B/1D) receptor agonists ('triptans') is not recommended, even in the absence of cardiovascular or cerebrovascular risk, and NSAID use should be limited because of potential gastrointestinal adverse effects. Prophylactic treatments include antidepressants, beta-adrenoceptor antagonists, calcium channel antagonists and antiepileptics. Selection of a drug from one of these classes should be dictated by the patient's co-morbidities. Beta-adrenoceptor antagonists are appropriate in patients with hypertension but are contraindicated in those with chronic obstructive pulmonary disease, diabetes mellitus, heart failure and peripheral vascular disease. Use of antidepressants in low doses is, in general, well tolerated by elderly people and as effective, overall, as in young adults. This approach is preferred in patients with concomitant mood disorders. However, prostatism, glaucoma and heart disease make the use of tricyclic antidepressants more difficult. Fewer efficacy data in the elderly are available for selective serotonin reuptake inhibitors, which can be tried in particular cases because of their good tolerability profile. Calcium channel antagonists are contraindicated in patients with hypotension, heart failure, atrioventricular block, Parkinson's disease or depression (flunarizine), and in those taking beta-adrenoceptor antagonists and monoamine oxidase inhibitors (verapamil). Antiepileptic drug use should be limited to migraine with high frequency of attacks and refractoriness to other treatments. Promising additional strategies include ACE inhibitors and angiotensin II type 1 receptor antagonists because of their effectiveness and good tolerability in patients with migraine, particularly in those with hypertension. Because of its favourable compliance and safety profile, botulinum toxin type A can be considered an alternative treatment in elderly migraine patients who have not responded to other currently available migraine prophylactic agents. Pharmacological treatment of migraine poses special problems in regard to both symptomatic and prophylactic treatment. Contraindications to triptan use, adverse effects of NSAIDs, and unwanted reactions to some antiemetics reduce the list of drugs available for the treatment of migraine attacks in elderly patients. The choice of prophylactic treatment (beta-adrenoceptor antagonists, calcium channel antagonists, antiepileptics, and more recently, some antihypertensive drugs) is influenced by co-morbidities and should be directed at those drugs that are believed to have fewer adverse effects and a better safety profile. Unfortunately, for most of these drugs, efficacy studies are lacking in the elderly.