Satsuma Pharmaceuticals' hopes for a timely FDA approval of its intranasal migraine therapy, STS101, have been dashed due to manufacturing problems. The FDA issued a complete response letter (CRL) citing chemistry, manufacturing, and controls (CMC) issues. This setback delays the potential availability of a new option for acute migraine treatment using a novel dry powder formulation of dihydroergotamine mesylate (DHE).
STS101: Aims and Setbacks
STS101, a dry powder intranasal formulation of DHE, was designed as a convenient and portable treatment for acute migraine attacks, with or without aura, in adult patients. DHE has been used to treat migraine since the 1940s. Satsuma aimed to improve upon existing DHE formulations like Migranal by Bausch Health, addressing limitations such as variable drug absorption and cumbersome administration. However, the recent CRL indicates that Satsuma has not yet adequately addressed manufacturing concerns raised by the FDA.
Competitive Landscape
The acute migraine market is becoming increasingly competitive. Impel Neuropharma received FDA approval for its Trudhesa nasal spray in 2021. Additionally, non-DHE options like Pfizer’s nasally-administered CGRP inhibitor Zavzpret (zavegepant) and oral CGRP inhibitors such as Pfizer’s Nurtec ODT (rimegepant) and AbbVie’s Ubrelvy (ubrogepant) have entered the market. Analysts had once projected peak sales of $400 million for STS101, but these projections were made before the program delays and the emergence of competing therapies.
Satsuma's Response
Satsuma intends to work with the FDA to address the CMC issues and resubmit the marketing application. Dr. Ryoichi Nagata, president and CEO of Satsuma, stated that the CRL did not raise concerns about the clinical data package and did not request new clinical trials. The company remains committed to completing the review process for STS101 as quickly as possible.
DHE in Migraine Treatment
DHE acts as an agonist at 5-HT1D receptors and has been a mainstay in migraine treatment for decades, initially administered intravenously and later via subcutaneous and intramuscular injections. While triptans and CGRP inhibitors have largely superseded DHE, some patients do not respond well to these alternatives, and DHE remains a valuable option. STS101 was designed to deliver optimal drug plasma levels, balancing efficacy with a reduction in adverse events like nausea and vomiting.
