Not long after a Friday morning earnings call in which Intelgenx Corp. CEO Horst Zerbe said his team was still awaiting word from the FDA on its resubmitted 505(b)(2) application for its acute migraine candidate, Rizaport Versafilm, that news arrived in the form of a complete response letter (CRL), its third following earlier CRLs in February 2014 and April 2019. Company shares, which trade on both the TSX Venture Exchange and OTCQX market plunged after a midmorning trading halt requested by the company, with the U.S.-listed shares (OTCQX:IGXT) falling 59.3% to 12 cents per share by 1 p.m. ET.
According to the Saint Laurent, Quebec-based company, the FDA said it can't approve the new drug application for Rizaport in its present form and requested additional information, though specifics were not disclosed. It did not request a new bioequivalence study, perhaps satisfied to accept previous bioequivalence data on the drug generated in 2012.
"Obviously, we are surprised and disappointed," said Zerbe. "We are committed to addressing the concerns raised by the FDA in the CRL. To that end, we will request a meeting with the agency as soon as reasonably possible to discuss the scope of the CRL comments to obtain clarification and determine next steps."
Rizaport is an oral thin-film formulation of the 5-HT1 receptor agonist rizatriptan, the active drug in Maxalt-MLT orally disintegrating tablets, a migraine product marketed by Merck & Co. Inc. It was co-developed with Tel Aviv, Israel-based Redhill Biopharma Ltd., which also helped commercialize it until terminating its agreement with Intelgenx at the end of 2017.
The medicine employs Intelgenx’s Versafilm technology, which consists of a thin polymeric film comprising components that are approved by the FDA for use in food, pharmaceutical and cosmetic products and are commonly used by breath-freshening strips.
Despite the medicine's troubles in the U.S., following a positive opinion for its MAA under the European decentralized procedure in 2015, it has since gained market approvals for the treatment of acute migraines in Germany, Luxembourg and Spain.