Squarex Announces Positive Results from Completed Phase 2 Study of SQX770 in the Prevention of Recurrent Herpes Labialis

ST. PAUL, Minn., Aug. 5, 2019 /PRNewswire/ -- Squarex, a clinical-stage pharmaceutical company developing a topical immunomodulator for the long-term prevention of recurrent cold sores and other infections caused by herpes simplex viruses, today announced positive results from a Phase 2 study of its investigational compound SQX770, a topical formulation of the immunomodulator squaric acid dibutyl ester (SADBE), in patients with recurrent herpes labialis. The company intends to initiate a Phase 3 clinical trial following a planned FDA end of phase 2 meeting later this year.

The multi-center, placebo-controlled, double-blinded randomized Phase 2 clinical trial involved 139 subjects who reported four or more herpes labialis episodes in the past 12 months. The study was designed to determine if the topical application of SADBE can delay outbreaks of HSV-1.

Results from the Phase 2 study demonstrated that a single topical dose of SQX770 applied to the upper arm significantly extended time to next herpes labialis outbreak and reduced both the frequency and severity of outbreaks. The greatest effect was recorded during days 43 to 121 following the drug's application. These findings suggest SQX770 immunotherapy can take up to 6 weeks to fully exert a clinically meaningful effect on the immune system.

Groups of patients received 1 or 2 doses of SQX770 or placebo.  During the span between days 43 and 121, both the 1-dose group, as well as the pooled treatment groups demonstrated statistically significantly superior results compared to the placebo group for the following endpoints:

• average number of outbreaks;
• time to next outbreak;
• proportion of subjects with an outbreak; and
• proportion of subjects with moderate or severe outbreaks.

No serious adverse events (SAEs) were reported. The adverse events (AE) that were reported, such as local reaction due to the sensitization and challenge responses on the skin were what investigators expected to see with a topical immunomodulator.

"We are extremely pleased with the results observed in the Phase 2 trial of SQX770," stated Jack Talley, Chief Executive Officer of Squarex. "Our findings confirm and validate the results from two previous studies including a previous placebo controlled clinical trial and therefore, pave the road for the initiation of a Phase 3 trial. With no current preventative treatment options on the market for the millions of patients who suffer from recurrent HSV-1 outbreaks, we are excited to continue the clinical development and hopefully becoming the first and only choice for combating herpes labialis – cold sores or oral herpes."

About SQX770
SQX770, Squarex's lead drug candidate, is a topical formulation of the immunomodulator squaric acid dibutyl ester (SADBE) for the prevention of recurrent cold sores (herpes labialis) and other infections caused by herpes simplex viruses. Now in Phase 2 clinical trials, it could be the first and only drug designed to prevent herpes labialis outbreaks to receive approval from the U.S. FDA.

About Herpes Labialis
Herpes labialis is a common condition characterized by blisters or erosions on the lips and skin around the mouth and nose. Most cases are caused by herpes simplex virus type 1 (HSV-1), but 10-15% of cases are caused by HSV-2 with this percentage reportedly increasing. The natural history of HSV-1 infection leading to herpes labialis is that the virus typically initially infects oral mucosa, and then migrates to sensory neurons and establishes latency, typically in the trigeminal ganglion.  The virus is later activated from latency by various events including fever, stress, cold or flu infection, immunosuppression, and sunlight.  Upon activation, the virus migrates down sensory neurons to epithelial cells, typically on the vermillion border of the lip, and causes cell lysis and outbreaks as epidermal lesions. Outbreaks typically last 1-2 weeks.  The frequency and severity of outbreaks is thought to be dependent on the effectiveness of immune control of the virus.

About Squarex
Squarex is a clinical-stage pharmaceutical company developing a topical formulation of the immunomodulator squaric acid dibutyl ester for the prevention of recurrent cold sores (herpes labialis) and other infections caused by Herpes Simplex Viruses. Its Phase 1/2 placebo-controlled clinical trial showed the drug was safe and effective in preventing cold sore outbreaks, tripling the time to next cold sore outbreak from 40 days to more than 120. When FDA approved, SQX770 would be the first and only drug on the market to prevent cold sore outbreaks in the more than 2% of the U.S. population with greater than six outbreaks per year.

Contacts:
Tiberend Strategic Advisors, Inc. 

Sharen Tilman (Investors)
[email protected]
(646) 604-5149

Johanna Bennett (Media)
[email protected]
(212) 375-2686

SOURCE Squarex