Pherin Pharmaceuticals lead program PH94B nasal spray, a Phase 3 ready product, is being developed for the acute treatment of Social Anxiety Disorder under USFDA guidance.

Pherin Pharmaceuticals

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Mental Illness

Effective Anxiety Disorder Medication

Social anxiety disorder, previously called social phobia, describes a collection of disorders that share many similar clinical features and treatment strategies. Social anxiety disorder is the most common anxiety disorder, with a lifetime prevalence of 13-14%; and it is among the most common psychiatric illness, ranking third after depression and substance abuse. Although both pharmacological and non-pharmacological therapies are considered useful in the treatment of social anxiety disorder, it is estimated that only 30%-50% of people with social anxiety disorder currently receive professional treatment. This disorder can significantly impair a person's occupational and social functioning, as well as place high economic demands on society.

Lonely Teen

Social Anxiety Disorder

Patients with social anxiety disorder experience a marked and persistent fear of most social or performance situations in which they believe embarrassment could occur. Exposure of these patients to social or performance situations almost invariably provokes an immediate anxiety response. The subjects learn either to avoid these situations or to endure them with dread. The avoidance, fear or anxious anticipation of these situations interferes significantly with the person's daily routine, having a marked impact on occupational functioning and social life.

In all instances, there is a discrete period of intense fear or discomfort, accompanied by both physical and cognitive symptoms that develop abruptly and reach a peak within minutes. These symptoms may include heart pounding, sweating, trembling, shortness of breath, nausea, dizziness and the fear of losing control or of dying. The severity of the episode varies widely, and it may occur daily, weekly or less frequently, depending on the exposure of the patient to the phobic situation.


Pharmaceuticals used to treat social anxiety disorder include beta-blockers, antidepressants such as selective serotonin reuptake inhibitors (SSRIs) and selective norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, monoamine oxidase inhibitors, and benzodiazepines. The use of these medications typically requires a prolonged period of treatment and is associated with some undesirable side effects. Furthermore, these medications must be taken daily, on a prophylactic basis. At Pherin Pharmaceuticals, we believe that a product with a novel mechanism of action, full safety profile, and very rapid onset of efficacy that is used on an on-demand basis as needed for treatment of social anxiety disorder could have substantial clinical and economic advantages over currently available medications.

Pherin completed favorable randomized, placebo-controlled, double-blind, longitudinal Phase 2 clinical trials, using PH94B nasal spray in patients diagnosed with social anxiety disorder. The analysis of 91 patients that completed treatment shows that PH94B reduced symptoms in 75.6%, as compared with placebo (37% only). PH94B was significantly superior to placebo to relieve performance anxiety symptoms (t = 3.16; p < .01) and social interaction anxiety (t = 2.67, p < .01) during a public speaking challenge. These effects were achieved within 15 minutes after intranasal administration of 800 nanograms (0.8 thousandths of a milligram) of PH94B.

Favorable Results

There were no adverse events, or side effects reported associated with the nasal administration of PH94B, and the medication was well tolerated by the treated individuals. After completion of the Phase 2B clinical trials, Pherin held a successful End-of-Phase 2-Meeting with the US Food and Drug Administration (US FDA) regarding PH94B. Based upon these favorable results, an updated version of Phase 3 clinical protocol was submitted to the US FDA to allow Pherin to move into Phase 3 clinical trials.

A Phase 3 pilot feasibility trial using PH94B nasal spray in men and women was completed. Men and women (mean age 40.2 years) who met predetermined criteria for event frequency and severity were randomized to two-weeks of treatment with PH94B or placebo, used on a PRN basis up to four times daily, self-administered 15-minutes before entering a feared situation. Patients carried a diary to rate the severity of their anxiety on a scale from 0 to 100 (SUD scores).

PH94B improved social anxiety symptoms on the primary endpoint (SUD scores) significantly better than placebo (p = 0.006), and the drug superiority over placebo was similar for men and women. PH94B also showed a significant advantage to placebo on several secondary endpoints as the Liebowitz Social Anxiety Scale (LSAS), Patient Global Improvement (PGI) and Clinical Global Improvement (CGI).

Adverse effects were mild and did not show drug-placebo differences. These findings are significant because they support the follow-up Phase 3 trials, and because PH94B could be the first systematically studied PRN treatment for Social Anxiety Disorder that could be used either as a monotherapy or as an adjunctive treatment.

In October 2018 VistaGen Therapeutics acquired worldwide license of Phase 3-Ready PH94B nasal spray from Pherin Pharmaceuticals for as-needed treatment of Social Anxiety Disorder.

Clinical Trial


Depression is a mood disorder characterized by extreme and persistent disruption of a person's usual emotional state, affecting physical health as well as how the sufferer feels, thinks, and behaves toward others. Depression is a physical disorder resulting from an imbalance of essential chemicals within the brain.

Because of its disabling effects and the possibility of suicide, major depression requires treatment. Depression is the most common psychiatric illness in the United States, afflicting an estimated 17.6 million people each year. The typical time of onset of depression is early middle age, and depression is particularly common among the elderly. It is estimated that untreated depression costs American employers as much as $43.0 billion per year through sick days, lost productivity, employee turnover and medical bills.

Depressed Man


The most commonly used treatments for depression are antidepressant medications, psychotherapy or a combination of the two. The major types of antidepressants currently available commercially include tricyclic antidepressants, monoamine oxidase inhibitors, selective serotonin reuptake inhibitors, and so-called new-generation antidepressants. These medications have significant side effects, and many have limitations related to the situations and patients in which they can be used. In most cases, antidepressant medications must be taken for four to six weeks before they begin to produce substantial improvement in a depressed person's mood. Furthermore, finding the right antidepressant at precisely the correct dosage for a given individual usually involves a significant period of trial and adjustment. In many cases, the use of adjunct medication has been found helpful in curbing the symptoms of depression during the period before antidepressant medication achieves its therapeutic efficacy.

PH10 Pherine

PH10 is being is being developed for its therapeutic advantages as an antidepressant treatment, particularly  during the early stage of treatment  for its vrapid onset of efficacy and very low incidence of side effects. 

Nasal Spray

An exploratory Phase 2A randomized study was conducted in 30 patients diagnosed with major depression, to compare the efficacy and safety of .4 and .8 micrograms PH10 and placebo self-administered intranasally in spray form up to 2 times daily.

Results show a significant dose-dependent effect of PH10 nasal spray on Hamilton Depression Scores significantly better from the impact of treatment with placebo. The clinical efficacy of PH10 nasal spray on Hamilton Depression Scores increased progressively starting on the first day of treatment and continuing along the 8-weeks treatment period.

In October 2018 VistaGen Therapeutics dcquired worldwide rights from POherin Pharmaceuticals to develop and commercialize PH10 for treatment of Major Depressive Disorder.