Focus on trial endpoints of clinical relevance and the use of almotriptan for the acute treatment of migraine

A novel test to compare two treatments based on endpoints involving both nonfatal and fatal events

In a clinical trial comparing two treatment groups, one commonly-used endpoint is time to death. Another is time until the first nonfatal event (if there is one) or until death (if not). Both endpoints have drawbacks. The wrong choice may adversely affect the value of the study by impairing power if deaths are too few (with the first endpoint) or by lessening the role of mortality if not (with the second endpoint). We propose a compromise that provides a simple test based on the time to death if the patient has died or time since randomization augmented by an increment otherwise. The test applies the ordinary two-sample Wilcoxon statistic to these values. The formula for the increment (the same for experimental and control patients) must be specified before the trial starts. In the simplest (and perhaps most useful) case, the increment assumes only two values, according to whether or not the (surviving) patient had a nonfatal event. More generally, the increment depends on the time of the first nonfatal event, if any, and the time since randomization. The test has correct Type I error even though it does not handle censoring in a customary way. For conditions where investigators would face no easy (advance) choice between the two older tests, simulation results favor the new test. An example using a renal-cancer trial is presented.

Treatment strategies for menstrually related migraine

Approximately 50% of migrainous women suffer from menstrually related migraine (MRM), a type of migraine in which the attacks occur at the same time as or near the menstrual flow. Attacks of MRM tend to be longer, more intense and disabling and sometimes less responsive to treatment than non-menstrual migraines. Similar to the management of non-menstrual migraine, the use of triptans and NSAIDs is the gold standard for MRM treatment. In this paper, the most important studies in the literature that report the effectiveness of triptans, of certain associated drugs and other analgesic agents are summarized. Preventive strategies that can be used if a prophylactic treatment is needed is also analyzed, with particular attention paid to the use of perimenstrual prophylaxis with triptans and/or NSAIDs. Moreover, considering the peculiar interaction between menstrual migraine and female sex hormones, brief mention is made to possible hormonal manipulations.

Intranasal ketorolac tromethamine (SPRIX®) containing 6% of lidocaine (ROX-828) for acute treatment of migraine: Safety and efficacy data from a phase II clinical trial

Objective

Ketorolac is a non-triptan, non-opioid, mixed cyclooxygenase (COX)1/2-inhibitor for short-term management of moderate-to-severe acute pain. This trial evaluated an intranasal formulation of ketorolac tromethamine (SPRIX®) containing 6% lidocaine (ROX-828) for the acute treatment of migraine with and without aura as defined by the International Headache Society.

Methods

Patients were randomly assigned 1:1 to self-treat with intranasal ROX-828 (31.5 mg ketorolac tromethamine/200 µL, containing 6% of lidocaine) or placebo (with 6% lidocaine) within four hours of a new migraine attack rated ≥ moderate in pain intensity. Assessments included headache intensity and associated migraine symptoms (nausea, vomiting, phonophobia, photophobia) measured at baseline and at regular intervals through 48 hours post-dosing, and global impression of efficacy (seven-point scale) measured at two hours.

Results

Randomized patients who had a migraine attack ( N = 140) were evaluable (ROX-828, N = 68; placebo, N = 72). Patients receiving ROX-828 showed a significant ( p < 0.05) improvement in pain relief at all time points except 0.5 and 24 hours compared with those who received placebo. More patients achieved pain-free status with ROX-828 than with placebo at 1.5, 3, 4, 24 and 48 hours ( p < 0.05); significance at the two-hour time point, which was the primary endpoint, was not met. Patients’ global impression of efficacy showed statistically significantly better results for patients receiving ROX-828 than for those receiving placebo. Associated migraine symptoms were significantly improved ( p < 0.05) with ROX-828 relative to placebo at several time points throughout the observation period. The most frequently reported adverse events in both groups were associated with nasal discomfort.

Conclusion

Self-administered intranasal ROX-828 was well tolerated. While the primary endpoint was not met, the results provide preliminary evidence that ROX-828 improves migraine pain.

Almotriptan for the treatment of acute migraine: a review of early intervention trials

Almotriptan is a serotonin (5-hydroxytryptamine)(1B/1D) receptor agonist (triptan) that has shown consistent efficacy in the acute treatment of migraine with excellent tolerability. It is an effective, well-tolerated and cost-effective triptan, as demonstrated by improvement in rigorous, patient-orientated end points, such as 'sustained pain-free without adverse events'. Results from post hoc analyses, observational studies and well-controlled, prospective clinical trials have shown that significant improvements can be achieved if almotriptan 12.5 mg is administered within an hour of migraine onset, particularly when pain is mild, rather than waiting until pain is moderate-to-severe. Benefits were also achieved with early treatment of moderate-to-severe pain. Time-to-treatment was the best predictor of headache duration, whereas initial headache intensity best predicted most other efficacy outcomes. Early administration of almotriptan 12.5 mg not only produced rapid symptomatic relief, it also improved the patient's quality of life and ability to resume normal daily functioning. Furthermore, the efficacy of almotriptan is not significantly affected by allodynia (purported to reduce the efficacy of triptans). Thus, the excellent efficacy and tolerability profile of almotriptan administered early in a migraine attack indicate that it may be a first-line treatment option in this common, underdiagnosed and undertreated disorder.

Allodynia-associated symptoms, pain intensity and time to treatment: predicting treatment response in acute migraine intervention

OBJECTIVE

To evaluate the relationship between treatment outcomes and allodynia-associated symptoms (AAS) at the time of treatment with almotriptan.

METHODS

Analyses were performed with data collected prospectively from patients in 2 recently completed early intervention trials, AXERT Early miGraine Intervention Study (AEGIS) and AXERT 12.5 mg time vs Intensity Migraine Study (AIMS): 2-hour pain free, 2-hour pain relief (AEGIS only), sustained pain free (SPF), use of rescue medication, and median headache duration (AIMS only), in the presence and absence of pretreatment AAS, which was determined by responses to a questionnaire. Analyses were conducted to evaluate possible prognostic variables.

RESULTS

The presence of pretreatment AAS did not have a significant effect on 2-hour pain-free, 2-hour pain-relief or SPF rates, use of rescue medication, or headache duration. Significant factors for most favorable outcomes (greater 2-hour pain-free, 2-hour pain-relief and SPF rates, less use of rescue medication, and shorter headache duration) included treatment with almotriptan 12.5 mg, treatment of mild or moderate headache pain, and treatment within 1 hour of headache onset.

CONCLUSION

Almotriptan 12.5 mg was efficacious in providing 2-hour pain free, 2-hour pain relief, SPF, and reducing rescue medication use irrespective of the presence of AAS at the time of treatment. The most optimal efficacy outcomes occurred when patients treated migraine attacks early and before the onset of severe pain. The presence of AAS, which may indicate an early phase of allodynia, did not influence the efficacy of almotriptan therapy.

Use of the sustained pain-free plus no adverse events endpoint in clinical trials of triptans in acute migraine

OBJECTIVE

To assess the relationship between the sustained pain free (SPF) and adverse event (AE) rates associated with six oral serotonin 5-HT(1B/1D) receptor agonists (triptans) used for the treatment of acute migraine, employing data from a previous meta-analysis (that included almotriptan, eletriptan, naratriptan, rizatriptan, sumatriptan and zolmitriptan, but not frovatriptan) in order to provide a rationale for the use of the rate of patients who are SPF plus no AE (SNAE) as an endpoint in trials of medications for acute migraine.

BACKGROUND

The attributes of drug treatment for acute migraine that are most important to people who experience them are complete pain relief, lack of recurrence, rapid onset and lack of AEs. The endpoints used to assess therapy for acute migraine do not always address these elements.

METHODS

The relationship between SPF and AE rates was explored using nonparametric regression techniques, and the box-plot method was used to identify outliers. The estimated SNAE rate for each triptan was calculated with and without assuming independence between efficacy and tolerability.

RESULTS

At the level of the individual agent, there was a significant relationship between the efficacy and tolerability of each triptan, with the exception of almotriptan 12.5 mg, which had an AE rate approximately 30% lower than would be expected, and eletriptan 20 mg, which had an AE rate approximately 20% higher than would be expected, on the basis of their efficacy. Almotriptan 12.5 mg and eletriptan 20 mg had the highest and lowest base-case values for SNAE, respectively, and both qualified statistically as outliers to the distribution of SNAE values obtained with the other triptans. The probability that each triptan was superior to the reference agent (sumatriptan 100 mg) in terms of SNAE was calculated across all possible values (at the level of the individual patient) for the relationship between efficacy and tolerability. Again, almotriptan 12.5 mg and eletriptan 20 mg had the highest and lowest values for their SNAE rates, respectively, and almotriptan 12.5 mg qualified statistically as an outlier from the distribution of the probabilities obtained for the other triptans.

CONCLUSION

This analysis determined that higher SPF rates were strongly associated with higher AE rates, with the notable exception of almotriptan 12.5 mg, which had a lower than expected AE rate, resulting in the highest SNAE rate of the included triptans and doses. SNAE is a useful measure that can be used to discriminate between therapies and this endpoint incorporates the attributes that are most relevant to patient satisfaction with treatment. We recommend calculation of the SNAE rate at the level of the individual patient in future clinical trials of medication for the treatment of acute migraine to facilitate selection of a treatment for acute migraine that offers the best chance for effective management.

Crossover, double-blind clinical trial comparing almotriptan and ergotamine plus caffeine for acute migraine therapy

In this randomized, double-blind, crossover clinical trial, adult patients treated two migraine attacks: one with almotriptan 12.5 mg and the other with ergotamine 2 mg plus caffeine 200 mg. Treatment with almotriptan was associated with a significantly greater proportion of patients achieving 2-h pain free (20.9% vs. 13.7%; P < 0.05) and 2-h pain relief (57.7% vs. 44.5%; P < 0.01) compared with ergotamine plus caffeine therapy; significant differences were not seen at 1 h. Rates for sustained pain free and sustained pain free plus no adverse events (AEs) also were significantly greater after almotriptan treatment than after the use of ergotamine plus caffeine (P < 0.05). Almotriptan was associated with a significantly lower rate of photophobia at 90 min (P < 0.05), phonophobia at 60, 90, and 120 min (P < 0.05 to <0.01), and nausea and vomiting at 90 and 120 min (P < 0.01) compared with ergotamine plus caffeine. A significantly greater proportion of patients were more satisfied with almotriptan than with ergotamine plus caffeine (P < 0.05). Sixteen patients reported adverse events during almotriptan treatment and 27 patients reported AEs during the ergotamine plus caffeine therapy. Most AEs were mild-to-moderate and did not result in treatment-related discontinuations. In conclusion, almotriptan was associated with significantly greater efficacy for treating migraine compared with ergotamine plus caffeine, was generally well tolerated and was associated with greater rate of treatment satisfaction.

Almotriptan and zolmitriptan in the acute treatment of migraine

OBJECTIVE

To compare almotriptan and zolmitriptan in the treatment of acute migraine.

METHODS

This multicentre, double-blind trial randomized adult migraineurs to almotriptan 12.5 mg (n = 532) or zolmitriptan 2.5 mg (n = 530) for the treatment of a single migraine attack. The primary end point was sustained pain free plus no adverse events (SNAE); other end points included pain relief and pain free at several time points, sustained pain free, headache recurrence, use of rescue medication, functional impairment, time lost because of migraine, treatment acceptability, and overall treatment satisfaction.

RESULTS

No significant difference was seen in SNAE (almotriptan 29.2% vs zolmitriptan 31.8%) or the other efficacy end points measured. The incidence of triptan-associated AEs and triptan-associated central nervous system AEs was significantly lower for patients receiving almotriptan compared to zolmitriptan.

CONCLUSIONS

Almotriptan and zolmitriptan were associated with similar efficacy and overall tolerability in the treatment of acute migraine. Almotriptan was associated with a significantly lower rate of triptan-associated AEs.