Efficacy and safety of 400 and 800 mg etodolac vs. 1,000 mg paracetamol in acute treatment of migraine: a randomized, double-blind, crossover, multicenter, phase III clinical trial

Have the IHS Guidelines for controlled trials of acute treatment of migraine attacks been followed? Laying the ground for the 4th edition

Background

The International Headache Society (IHS) has published four editions of Guidelines for acute clinical trials in migraine in the past 28 years. This continuous update process has been driven by the increasing amount of scientific data in the field of migraine and by the need to continuously improve the quality of trials.

Objectives

To illustrate: i) the results of the analysis on the adherence of published trials to the 3rd edition published in 2012, in order to identify the critical areas that needed to be addressed in the 4th edition and ii) the changes introduced in this latter edition for improving adherence and methodology robustness.

Methods

We searched and reviewed all controlled trials on acute treatment of migraine published in the period 2012–2018 and we assessed their adherence to the 3rd edition of the IHS Guidelines using a score system based on the most important recommendations. Afterwards, we compared the two editions of the Guidelines and assessed the changes between them.

Results

We included data from 24 controlled clinical trials. Most trials had a randomized double-blind controlled (RDB) design, while a minority (16.7%) were non-randomized double-blind trials. Less than half (44.6%) of the RDB trials used the recommended “pain-free at 2 hours” endpoint as the primary efficacy measure. Trial design and evaluation of results were the areas that diverged the most from the recommendations.

Conclusion

Adherence to IHS guidelines for clinical trials has been suboptimal so far. The new edition has been adapted and optimized to facilitate uptake and strengthen the quality of evidence.

Evaluating the reporting of adverse events in controlled clinical trials conducted in 2010–2015 on migraine drug treatments

Background

In 2008, the International Headache Society published guidelines on the “evaluation and registration of adverse events in clinical drug trials on migraine”. They listed seven recommendations for reporting adverse events in randomized controlled trials on migraine. The present study aimed to evaluate adherence to these recommendations, and based on the results, to recommend improvements.

Methods

We searched the PubMed/MEDLINE database to identify controlled trials on migraine drugs published from 2010 to 2015. For each trial, we noted whether five of the recommended parameters were presented. In addition, we noted whether adverse events were reported in abstracts.

Results

We identified 73 trials; 51 studied acutely administered drugs and 22 studied prophylactic drugs for migraine. The number of patients with any adverse events were reported in 74% of acute-administration and 86% of prophylactic drug trials. Only 30 (41%) of the 73 studies reported adverse events with data in the abstracts, and 27 (37%) abstracts did not mention adverse events.

Conclusion

Adverse events, both frequency and symptoms, should be reported to allow a fair judgement of benefit/tolerability ratio when randomized controlled trials in migraine treatment are published. Clinically significant adverse events should be included in the abstract of every randomized controlled trial in migraine treatment.

Recent advances in migraine therapy

Migraine is a common and highly disabling neurological disorder associated with a high socioeconomic burden. Effective migraine management depends on adequate patient education: to avoid unrealistic expectations, the condition must be carefully explained to the patient soon as it is diagnosed. The range of available acute treatments has increased over time. At present, abortive migraine therapy can be classed as specific (ergot derivatives and triptans) or non-specific (analgesics and non-steroidal anti-inflammatory drugs). Even though acute symptomatic therapy can be optimised, migraine continues to be a chronic and potentially progressive condition. In addition to the drugs officially approved for migraine prevention by international governmental regulatory agencies, numerous different agents are commonly used for this indication, showing various levels of evidence of efficacy and tolerability. Guidelines published in recent years, based on evidence-based medicine data on migraine prophylaxis, are a useful source of guidance, especially for primary care physicians and neurologists without specific expertise in headache medicine. Although the field of pharmacological migraine prevention has seen few advances in recent years, potential novel approaches are now being developed. This review looks at emerging pharmacological strategies for acute and preventive migraine treatment that are nearing or have already entered the clinical trial phase. Specifically, it discusses preclinical and clinical data on compounds acting on calcitonin gene-related peptide or its receptor, the serotonin 5-HT1F receptor, nitric oxide synthase, and acid-sensing ion channel blockers.

Acute Treatment of Migraine

Migraine is one of the most frequent disabling neurological conditions with a major impact on the patient's quality of life. Migraine has been described as a chronic disorder that characterized with attacks. Attacks are characterized by moderate-severe, often unilateral, pulsating headache attacks, typically lasting 4 to 72 hours. Migraine remains underdiagnosed and undertreated despite advances in the understanding of its pathophysiology. This article reviews management of migraine acute pharmacological treatment. Currently, for the acute treatment of migraine attacks, non-steroidal anti-inflammatory drugs (NSAIDs) and triptans (serotonin 5HT1B/1D receptor agonists) are recommended. Before intake of NSAID and triptans, metoclopramide or domperidone is useful. In very severe attacks, subcutaneous sumatriptan is first choice. The patient should be treated early in the attack, use an adequate dose and formulation of a medication. Ideally, acute therapy should be restricted to no more than 2 to 3 days per week to avoid medication overuse.

Paracetamol (acetaminophen) with or without an antiemetic for acute migraine headaches in adults

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 11, 2010 (Derry 2010). Migraine is a common, disabling condition and a burden for the individual, health services and society. Many sufferers choose not to, or are unable to, seek professional help and rely on over-the-counter analgesics. Co-therapy with an antiemetic should help to reduce nausea and vomiting, which are commonly associated with migraine.

OBJECTIVES

To determine the efficacy and tolerability of paracetamol (acetaminophen), alone or in combination with an antiemetic, compared with placebo and other active interventions in the treatment of acute migraine in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and the Oxford Pain Relief Database for studies through 4 October 2010 for the original review, and to 13 February 2013 for the update. Two clinical trials registers (ClinicalTrials.gov and gsk-clinicalstudyregister.com) were also searched on both occasions.

SELECTION CRITERIA

We included randomised, double-blind, placebo- or active-controlled studies using self-administered paracetamol to treat a migraine headache episode, with at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Numbers of participants achieving each outcome were used to calculate relative risk and numbers needed to treat (NNT) or harm (NNH) compared with placebo or other active treatment.

MAIN RESULTS

Searches for the update identified one additional study for inclusion. Eleven studies (2942 participants, 5109 attacks) compared paracetamol 1000 mg, alone or in combination with an antiemetic, with placebo or other active comparators, mainly sumatriptan 100 mg. For all efficacy outcomes paracetamol was superior to placebo, with NNTs of 12 (19% response with paracetamol, 10% with placebo), 5.0 (56% response with paracetamol, 36% with placebo) and 5.2 (39% response with paracetamol, 20% with placebo) for 2-hour pain-free and 2- and 1-hour headache relief, respectively, when medication was taken for moderate to severe pain.Paracetamol 1000 mg plus metoclopramide 10 mg was not significantly different from oral sumatriptan 100 mg for 2-hour headache relief; there were no 2-hour pain-free data.Adverse event rates were similar between paracetamol and placebo, and between paracetamol plus metoclopramide and sumatriptan. No serious adverse events occurred with paracetamol alone, but more serious and/or severe adverse events occurred with sumatriptan than with the combination therapy (NNH 32).

AUTHORS' CONCLUSIONS

Paracetamol 1000 mg alone is statistically superior to placebo in the treatment of acute migraine, but the NNT of 12 for pain-free response at two hours is inferior to at of other commonly used analgesics. Given the low cost and wide availability of paracetamol, it may be a useful first choice drug for acute migraine in those with contraindications to, or who cannot tolerate, non-steroidal anti-inflammatory drugs (NSAIDs) or aspirin. The addition of 10 mg metoclopramide gives short-term efficacy equivalent to oral sumatriptan 100 mg. Adverse events with paracetamol did not differ from placebo; serious and/or severe adverse events were slightly more common with sumatriptan than with paracetamol plus metoclopramide.