The FDA approval for Emend is based on two multicenter studies of 1,658 patients undergoing open abdominal surgery. Patients were randomized to receive Emend 40mg one to three hours before anesthesia or GlaxoSmithKline’s Zofran 4mg given intravenously immediately before anesthesia.
The studies found that Emend 40mg was superior to Zofran 4mg IV in preventing vomiting through 24 hours following surgery.
A single 125mg dose of Emend was also studied. However, no additional clinical benefit was seen as compared to the 40mg dose.
Emend belongs to a class of medications called substance P/neurokinin 1 (NK-1) receptor antagonists and is believed to work through a novel mechanism that primarily blocks nausea and vomiting signals to the brain.
This novel mechanism is distinct from how current anti-vomiting therapies work, including 5-HT3 receptor antagonists, such as Zofran, which primarily target nausea and vomiting signals in the gut. Emend represents the first new class of therapy for the management of postoperative nausea and vomiting (PONV) in more than 10 years.