Lundbeck and Otuska’s brexpiprazole hits the mark in PTSD trial

Lundbeck and Otuska’s brexpiprazole-sertraline cocktail has hit the mark in a post-traumatic stress disorder (PTSD) phase 2. The data give Lundbeck a boost at a time when its recently installed CEO is hunting for ways to improve on lackluster growth forecasts.

Investigators enrolled 321 patients in the trial and randomized them to receive placebo, sertraline or brexpiprazole as monotherapies or the two drugs in combination. Lundbeck was looking to the trial for evidence that serotonin-dopamine activity modulator brexpiprazole—sold under the brand name Rexulti—improves scores on a PTSD scale, either when given as a monotherapy or in combination.   

The brexpiprazole monotherapy arm failed to beat placebo. Sertraline, a selective serotonin reuptake inhibitor also known as Zoloft, also failed to move the needle. But the two drugs in combination bested the control, resulting in the trial hitting its primary endpoint with a p value of less than 0.01.

Lundbeck and Otsuka are yet to provide a detailed look at the data, but the snippets they have shared paint the trial in a positive light. The combination hit multiple, as-yet-undisclosed secondary goals. Lundbeck described the safety and tolerability data as “good” and in line with previous data on the drugs.

The next step is to find out what the FDA makes of the data and their implications for the future of brexpiprazole in PTSD. Lundbeck and Otsuka plan to meet with the agency to get its take by the end of the year.

A positive outcome from the meeting and, further down the line, the delivery of validatory clinical data would open up new opportunities for an important drug for Lundbeck. Brexpiprazole won FDA approval in major depressive disorder in 2015, but its efforts to expand the list of indications have hit some snags. 

Mixed data from a pair of phase 3 trials of brexpiprazole as a treatment for agitation in Alzheimer’s disease led Lundbeck and Otsuka to roll the dice on a third study. If the trial hits its goals, Lundbeck could bring brexpiprazole to market in the Alzheimer’s indication around 2022.

The pressure on brexpiprazole to deliver in Alzheimer’s and, to a lesser extent, PTSD, has grown as other pipeline prospects have faltered and approved products have run into commercial challenges. Notably, antipsychotic Lu AF35700 failed a phase 3 trial in treatment-resistant schizophrenia, taking a chunk out of Lundbeck’s stock price and depriving CEO Deborah Dunsire of a driver of growth.