A sensitive LC-MS/MS method was developed and validated for the quantification of almotriptan in rat brain and blood dialysates. Almotriptan is a 5HT1B/1D receptor agonist used for the treatment of migraine pain. Method consists of rapid gradient elution program with 10mM ammonium formate (pH 3) and acetonitrile on a Xbridge column. The MRM transitions monitored were m/z 336.2-58.1 for almotriptan and m/z 448.2-285.3 for the IS. The assay was linear in the range of 0.1-20ng/ml, with acceptable precision and accuracy along with adequate sensitivity. The between batch accuracy was in the range of 99.0-104.3% with precision in between 0.6% and 5.8%. Microdialysis is an important sampling technique, with the capability of capturing the concentrations of various analytes in different bio fluids, at a single time point. This method was applied to quantify brain and blood dialysate samples obtained from a microdialysis study of rats treated with almotriptan (10mg/kg, p.o.). In vivo recovery experiments were performed to correct the dialysate concentrations into extracellular concentrations. Mean peak dialysate concentrations of almotriptan were found to be 152±78 and 7.4±1.0ng/ml in blood and prefrontal cortex, respectively. The brain penetration of almotriptan is characterized by the AUCbrain/AUCblood found to be 0.07±0.05. The results revealed the importance of measuring the unbound almotriptan concentrations in the brain over the blood for understanding its PK/PD relationship.

Migraine is a common disease in children and adolescents. The incidence of migraine has increased alarmingly in the general population during recent decades. Migraine causes considerable individual suffering and impaired quality of life. Therefore, appropriate management is essential. In this article, the treatment of acute migraine in children and adolescents will be reviewed. Only a few randomized controlled studies have been published and high placebo rates are a major problem for proving superiority of active drugs. Generally, acetaminophen (paracetamol) and ibuprofen are accepted as drugs of first choice, even though the evidence is poor for the former and limited for latter. Among 14 studies on triptans in adolescents, 9 showed some superiority over placebo with respect to pain relief and pain freedom, and among 6 studies in children, 5 suggest some superiority over placebo. Sumatriptan nasal spray and zolmitriptan nasal spray have been approved for adolescents in Europe; almotriptan has been approved for adolescents in the USA, as has rizatriptan for patients aged 6-17 years. A recent study demonstrated the efficacy of a fixed combination of sumatriptan and naproxen in adolescents with migraine. In conclusion, evidence for the pharmacological treatment of acute migraine in children is very poor and evidence for adolescents is better but still limited.

Introduction: Migraine is a multifactorial neurovascular disorder characterized by recurrent episodes of disabling pain attacks, accompanied with gastrointestinal, neurological systems dysfunction. The pharmacologic treatment of migraine is classically divided in the management of the acute attack and preventive strategies. Triptans represent a powerful pharmacological tool in acute migraine treatment. However, a significant portion of treated patients cannot have access to this class due to possible adverse affects. Today, a total of seven triptan molecules are available, representing a commonly prescribed migraine treatment. Areas covered: The authors take a systematic approach to discuss the pharmacodynamic and pharmacokinetic aspects of almotriptan . They consider the emerging data on the clinical efficacy in the treatment of migraine and menstrual-related migraine. The data were obtained by searching the following key words in MEDLINE: pharmacokinetic, pharmacodynamic, triptans, almotriptan, migraine, menstrual migraine, relatively to the period 1989 - 2012. Expert opinion: The excellent efficacy and superior tolerability profile of almotriptan administered early offer a potential improvement over existing triptans for the symptomatic treatment of migraine attacks. Compared with other triptans, the different pathways involved in the metabolism of almotriptan ensure a limited variability of clinical response to the drug, making it less susceptible to the individual genomic background.

Menstrual migraine (MM) is a highly prevalent condition associated with considerable disability. Migraine attacks occur exclusively around the menstrual period in approximately 10% of women with migraine, that is, pure menstrual migraine, while at least 50% of them also experience migraine at other times of the month, that is, menstrually related migraine (MRM). The therapeutic approach to patients with MRM is based on treatment of the attack, or prophylactic strategies. Triptans are recommended as first-line treatments for moderate to severe migraine attacks, including MM. Frovatriptan is one of the newest triptans. Its high affinity for 5-HT receptors and long half-life contribute to its distinctive clinical effect, characterized by a more sustained and prolonged effect than other triptans. Indeed, frovatriptan proved to be effective in treating the acute attack, but was particularly effective in the short-term preventive therapy of MM. In addition, frovatriptan is one of the safest triptans, with the lowest risk of treatment-emergent adverse events. Following extensive evidence from randomized pharmacological trials, frovatriptan has now gained a grade A recommendation from the guidelines for short-term prophylaxis of MM. Recent analyses of direct comparative trials also suggest that frovatriptan might have an important role in the acute treatment of MRM. In these studies, frovatriptan showed pain relief and pain-free rates similar to those of zolmitriptan, rizatriptan, and almotriptan, but with significantly lower recurrence rates. More well-designed, randomized, prospective studies, specifically enrolling women with MM, will be needed in the near future to confirm the efficacy of frovatriptan in this migraine subtype.

This study was aimed determining the effectiveness, tolerance and satisfaction of patients with migraine as regards different triptans, according to the characteristics of their attacks. At the same time it sought to establish a predictive model that can be used to recommend one or another, depending on those characteristics.Retrospective observation-based study conducted in headache units in a number of different centres. Patients included in the study were those with migraine who used the same triptan to treat their attacks. Data concerning preference, effectiveness, speed and tolerance were analysed.The analysis included 160 patients (88 females), with a mean age of 42.92 years. The most commonly used triptans were eletriptan, almotriptan and rizatriptan. Both patients and doctors reported a high degree of satisfaction (88% and 65%) with the triptan that was used. In the surveys on preference, patients preferred their current triptan to the previous one (83%) or to non-specific drugs. The overall score on a visual analogue scale was above 7 for all the triptans, without any differences from one to another. On analysing the use of a particular triptan depending on the characteristics of the attacks, no statistically significant differences were found.In this selected group of patients, triptans are a treatment that patients claim to be very satisfied with. Although there are no overall differences in the scores among different triptans, the fact that certain triptans are used more by patients after previous experiences with others suggests that they are more effective. We did not find any parameter that predicts the use of a particular triptan.

OBJECTIVES

To conduct a systematic review and analysis of trial data submitted to the US Food and Drug Administration (FDA) to identify possible causes for the failure of pediatric trials of triptans for treatment of migraines. DATA SOURCE The FDA website for drug information and published literature. STUDY SELECTION All pediatric efficacy and pharmacokinetics trial data of drugs used for abortive treatment of migraine submitted to the FDA from January 1, 1999, through December 31, 2011. MAIN OUTCOME MEASURES Patient demographic baseline characteristics, inclusion and exclusion criteria, trial designs, efficacy end points, and pharmacokinetic profiles were analyzed and compared across drug products.

RESULTS

We analyzed data for sumatriptan succinate nasal spray and zolmitriptan, eletriptan hydrobromide, almotriptan malate, and rizatriptan benzoate tablets. Seven efficacy trials had a randomized, double-blinded, placebo-controlled, parallel-group trial design. In 4 trials, patients were required to have a history of migraine attacks lasting at least 4 hours. High response rates for placebo were observed in all trials, with pain relief at 2 hours ranging from 53% to 57.5%. Nonrandomization of patients with an early placebo response design was used in the rizatriptan trial in 2011. Compared with the rizatriptan trial conducted in 1999, the 2011 rizatriptan trial reduced the placebo response rate by 6% for headache freedom at the 2-hour posttreatment end point owing to study design. The pharmacokinetic profiles between adolescents and adults were statistically similar.

CONCLUSIONS

High placebo response rates are consistent across all trials and may represent the principal challenge in pediatric trials of drugs for abortive treatment of migraine. Enrichment with selection of subjects with long-lasting migraine attacks is not sufficient to overcome high placebo response rates. Another enrichment strategy, the nonrandomization of patients with an early placebo response, successfully reduces the high placebo response rate for rizatriptan and is a trial design that should be considered for future pediatric trials of abortive migraine therapeutics.

Frovatriptan (Migard®; Frova®) is an orally administered triptan approved for the acute treatment of adults with migraine, with or without aura. This article reviews the pharmacology of frovatriptan, focusing on its efficacy and tolerability. The precise mechanism of action of frovatriptan is unknown, but is thought to stem from agonism at serotonin 5-HT(1B) and 5-HT(1D) receptors, resulting in inhibition of intracranial and extracerebral artery vasodilation, along with possible anti-inflammatory and pain inhibiting effects. Frovatriptan appears to be functionally selective for 5-HT receptors in human basilar arteries over coronary arteries, which could translate into a low cardiovascular risk. In contrast to other triptans, frovatriptan has a long terminal elimination half-life in blood of ≈26 hours, which can be expected to be associated with a sustained treatment effect. Oral frovatriptan 2.5 mg was efficacious in patients with moderate to severe migraine attacks; in randomized, double-blind trials the proportion of patients with headache response at 2 hours (primary endpoint) was consistently significantly higher in frovatriptan than placebo groups. Frovatriptan was generally well tolerated in short-term clinical trials and when used over the longer term. The most frequent treatment-emergent adverse events occurring at a frequency ≥1% higher in frovatriptan than placebo recipients were dizziness, fatigue, headache, paraesthesia, flushing, skeletal pain, hot or cold sensation, dry mouth, chest pain and dyspepsia. In a study in patients with coronary artery disease, or who were at high risk of coronary artery disease, there was no increase over placebo in the occurrence of clinically significant ECG changes or in cardiac rhythm disturbances. In a further trial, frovatriptan administered early in a migraine attack was more efficacious than placebo followed by later administration of frovatriptan as pain progressed. Three crossover trials compared early administration of frovatriptan 2.5 mg with almotriptan 12.5 mg, rizatriptan 10 mg and zolmitriptan 2.5 mg in patients with migraine. There were no significant between-group differences in patient drug preference scores (primary endpoint) or in other endpoints, except for headache recurrence, which favoured frovatriptan in two of the trials. The trials did not test noninferiority of frovatriptan to the comparator. In a placebo-controlled trial that included a sumatriptan active treatment arm, sumatriptan 100 mg was significantly more efficacious than frovatriptan 2.5 mg for this primary endpoint. Frovatriptan was generally better tolerated than all four triptan comparators. In summary, frovatriptan was an efficacious acute treatment for moderate to severe migraine attacks and had a favourable tolerability profile, although in a single trial, it was not as efficacious as sumatriptan. Administration of frovatriptan early in an attack while the attack was at a mild level of intensity was more efficacious than late administration. Furthermore, in clinical trials adopting this early administration strategy, frovatriptan was not significantly less efficacious than almotriptan, rizatriptan and zolmitriptan, appeared to have a more sustained treatment effect, and was better tolerated than the comparators. Frovatriptan provides an alternative treatment for migraine, especially in patients who have had adverse events or frequent headache recurrences with triptans or other antimigraine drugs, and who are amenable to adopting an early administration strategy.

A simple, sensitive and selective method has been developed for quantification of Almotriptan (AL) in human plasma using Almotriptan-d(6) (ALD6) as an internal standard. Almotriptan and Almotriptan-d(6) were detected with proton adducts at m/z 336.1→201.1 and 342.2→207.2 in multiple reaction monitoring (MRM) positive mode, respectively. The method was linear over a concentration range of 0.5-150.0 ng/mL. The limit of detection (LOD) and limit of quantification (LOQ) for Almotriptan were 0.2 pg/mL and 0.5 ng/mL, respectively. Liquid-liquid extraction was used followed by MS/MS (ion spray). The method was shown to be precise with an average within-run and between-run variation of 0.68 to 2.78% and 0.57 to 0.86%, respectively. The average within-run and between-run accuracy of the method throughout its linear range was 98.94 to 102.64% and 99.43 to 101.44%, respectively. The mean recovery of drug and internal standard from human plasma was 92.12 ± 4.32% and 89.62 ± 6.32%. It can be applied for clinical and pharmacokinetic studies.

Two stability indicating chromatographic methods were proposed for the determination of almotriptan, eletriptan, and rizatriptan, in presence of their acid degradation products. The first method is a quantitative densitometric thin layer chromatography. The developing systems were; acetonitrile: methanol: dichloromethane: ammonia (10:6:3:1 v/v), ethyl acetate: methanol: ammonia (15:4:1 v/v), and methanol: acetonitrile: ammonia (9:4:1 v/v) for almotriptan, eletriptan and rizatriptan respectively. The TLC plates were scanned at 235 nm. Linear relationships were obtained over concentration ranges (5-50 μg/spot) for almotriptan and rizatriptan, and (5-60 μg/spot) for eletriptan. The second method based on the separation and determination of the studied drugs, using RP-HPLC technique. The separation was achieved on C18 Hypersil column, elution was carried out using phosphate buffer pH 3: methanol: acetonitrile (2: 1:1 v/v) at flow rate 2 mL/min and UV detection at 235 nm. Linear relationships were obtained over concentration ranges (10-200 μg/mL) for almotriptan and eletriptan, and (10-180 μg/mL) for rizatriptan. The chromatographic methods were successfully applied for the determination of each of the studied drugs in pure form, tablet form, and in laboratory prepared mixtures with their acid degradation products.

The objective of this study was to review the efficacy and safety of frovatriptan (F) versus rizatriptan (R), zolmitriptan (Z) and almotriptan (A), in women with menstrually related migraine (IHS criteria) through a pooled analysis of three individual studies. Subjects with a history of migraine with or without aura were randomized to F 2.5 mg or R 10 mg (study 1), F or Z 2.5 mg (study 2), and F or A 12.5 mg (study 3). The studies had an identical multicenter, randomized, double-blind, crossover design. After treating three episodes of migraine in no more than 3 months with the first treatment, patients had to switch to the next treatment for other 3 months. 346 subjects formed intention-to-treat population of the main study; 280 of them were of a female gender, 256 had regular menses and 187 were included in the menstrual migraine subgroup analysis. Rate of pain free at 2, 4 and 24 h was 23, 52 and 67 % with F and 30, 61 and 66 % with comparators (P = NS). Pain relief episodes at 2, 4 and 24 h were 37, 60 and 66 % for F and 43, 55 and 61 % for comparators (P = NS). Rate of recurrence was significantly (P < 0.05) lower under F either at 24 h (11 vs. 24 % comparators) or at 48 h (15 vs. 26 % comparators). Number of menstrual migraine attacks associated with drug-related adverse events was equally low (P = NS) between F (5 %) and comparators (4 %).