A nasal gel version of the motion sickness drug scopolamine has failed to make the grade with the FDA. The U.S. regulator has sent a complete response letter (CRL) to Defender Pharmaceuticals, rejecting DPI-396 for the prevention of nausea and vomiting induced by motion.
Barry Feinberg, M.D., the CEO of Defender, a privately held St. Louis company, said in a release that the firm will schedule a meeting with the FDA so it can “understand the issues raised in the CRL so we can develop and implement a comprehensive action plan.”
“We remain confident that our intranasal scopolamine is a safe and effective therapy,” Feinberg added.
In 2012, the NASA teamed with Irvine, California-based Epiomed Therapeutics to develop a nasal spray version of scopolamine. Astronauts often experience motion sickness in space. Two years later, Defender purchased Epiomed, according to the St. Louis Post-Dispatch.
Also working to develop the treatment has been the U.S. Naval Medical Research Unit. If Defender can gain approval of DPI-396, the company plans to make it available to the military first then offer it on the open market.
Novartis previously won an FDA approval for a scopolamine patch in 2012, according to a consumer pamphlet (PDF) posted online. The FDA first approved scopolamine in 1979, according to the drug's label.
The patch is administered behind the ear and is commonly used by people travelling through the air or at sea. It is also used to prevent postoperative nausea.
While effective for days, the treatment causes drowsiness. Defender’s formulation of intranasal scopolamine is a smaller, more concentrated dose designed for more rapid absorption.
It was found effective compared to placebo in a phase 3 study of more than 500 participants who were exposed to motion on an ocean trip. Those using DPI-396 were less likely to vomit, to have moderate to severe nausea or to request antihistamine rescue treatment.
The company and NASA also are conducting a phase 2 trial, recruiting astronauts to undergo motion simulation exercises, testing their ability to maintain their balance and execute motor skills like writing and other movements while avoiding nausea.
Defender has other potential uses in mind for DPI-396, such as combating depression and avoiding motion sickness when wearing virtual reality goggles.

https://www.pharma.com/pharma/fda-rejects-defenders-motion-sickness-nasal-gel-candidate