PH94B for Generalized Anxiety Disorder (GAD)
Generalized anxiety disorder (GAD) is a common chronic neuropsychiatric disorder characterized by persistent, debilitating and excessive concern and worry about family, friends, health, money, work, or other everyday issues and situations. Individuals with GAD find it difficult to control their worry and may worry more about actual circumstances than seems appropriate. They may also expect the worst even when there is no apparent reason to do so. GAD is diagnosed when an individual is unable or finds it difficult to control worry on more days than not for at least six months and has three or more of the many symptoms of GAD, such as excessive and ongoing worrying and tension, an unrealistic view of problems, restlessness, irritability, difficulty concentrating, or being easily startled. This differentiates GAD from worry that may be specific to a set stressor or for a more limited period of time. According to the Anxiety and Depression Association of America, GAD affects approximately 6.8 million adults in the U.S. in any given year. GAD comes on gradually and can begin across the life cycle, though the risk is highest between childhood and middle age.
People with GAD do not know how to stop the worry cycle and feel it is beyond their control, even though they usually realize that their anxiety is more intense than the situation warrants. Many individuals with GAD may avoid situations because they have the disorder, or they may not take advantage of important professional or social opportunities in their lives due to their anxiety and worry. When their anxiety is severe, it is difficult for individuals with GAD to carry out even the simplest of daily activities. Currently, the standard of care for GAD includes psychotherapy and certain medications with limited therapeutic benefits and various side effects and safety concerns, including antidepressants (SSRIs and SNRIs) and benzodiazepines.
PH94B demonstrated efficacy in a small placebo-controlled study in patients with GAD. Twenty-one patients were randomized to receive 200 pg PH94B or placebo in a one second aerosol pulse to the chemosensory epithelium of the anterior nasal septum. Thirty minutes after treatment there was mean reduction of 32.0% for the PH94B group and 19.6% for the placebo group in the total Hamilton Anxiety Rating Scale (HAM-A) score. Electrophysiological changes (respiratory, cardiac, and electrodermal frequency), concordant with the reduction in anxiety, were significantly greater for the PH94B group. These transient anti-anxiety effects of PH94B may warrant further investigation in a Phase 2b GAD trial.