Low efficacy of transdermal sumatriptan in migraine

Safety Problems With a Transdermal Patch for Migraine: Lessons From the Development, Approval, and Marketing Process

OBJECTIVE

We sought to analyze publicly available information about patient harm associated with an iontophoretic sumatriptan patch, to identify what went wrong and to suggest ways in which similar problems might be prevented in the future.

BACKGROUND

The Zecuity® sumatriptan iontophoretic transdermal system was marketed for acute treatment of migraine. The patch was withdrawn less than 10 months after its introduction because of multiple reports of scarring and burning. As of 2018, the FDA Adverse Event Reporting System public dashboard lists a total of 2889 reports of safety problems with the patch, 904 of which were classified as serious.

METHODS

For this narrative review, we examined US Food and Drug Administration documents related to the new drug application for this product and its approval. We searched Clinicaltrials.gov, PubMed, Google, Facebook, Twitter, and Instagram public posts for relevant information relating to the patch, its approval, marketing, and complications.

RESULTS

The FDA knew about problems with burns and scarring prior to approval of the product, and turned down the initial new drug application for this reason and because of other quality problems with the patch. The reapplication was approved despite continued concerns of several FDA reviewers about safety. The approval required the manufacturer to comply with enhanced postmarketing safety reporting. However, product information and labeling did not mention the possibility of burns or scarring. Approval was based on 1 clinical trial and 2 open label studies in which reporting of adverse events was suboptimal. The clinical trials had been prospectively registered but outcomes had been changed around the time the trial concluded. Aggressive marketing efforts and social media activity may have contributed to inaccurate perceptions of safety and efficacy, but social media also provided a written and photographic record of burns and other harm suffered by patients who used the patch.

CONCLUSIONS

Our review identified several problems with the development, testing, approval, and marketing of the Zecuity patch. To improve the process of developing headache treatments, it is important to consider the lessons that can be drawn from an examination of this high-profile failure of the drug development and regulatory system.

Sumatriptan: a review of its pharmacokinetics, pharmacodynamics and efficacy in the acute treatment of migraine

INTRODUCTION

Sumatriptan was developed more than 20 years ago as a 5-HT1B/1D receptor agonist, the first drug in a new class of specific anti-migraine drugs, the triptans. A large amount of information and experience has been gained from the clinical trials undertaken as well the various formulations of sumatriptan used over this period of time.

AREAS COVERED

This evaluation specifically reviews the pharmacokinetics, pharmacodynamics, clinical efficacy, and safety of different formulations and dosages of sumatriptan used for the acute treatment of migraines. Special clinical trials of the timing of dosage and sumatriptan in combination with other triptans as well as non-triptan drugs are also included.

EXPERT OPINION

Oral sumatriptan is effective, but not in a convincing majority (60%) of patients in clinical trials. Sumatriptan has failed to show superiority over more standard and cheaper treatment such as aspirin or aspirin plus metoclopramide. In addition, migraine patients want to quickly become pain free, and to remain pain free, but oral sumatriptan at 100 mg managed to keep patients pain free for 24 h is only 20% of cases. Even though sumatriptan has been a major step forward in providing a new specific therapy for the treatment of migraines, there are still are limitations in its use. There is still an unmet need to develop new non-triptan, anti-migraine drugs which act as effective treatment for those who suffer with migraines.