US-based biotechnology firm Strategic Science and Technologies (SST) has started a Phase I trial of its product candidate SST-6006 to treat women with female sexual arousal disorder (FSAD).

SST-6006 is a first-in-class topical sildenafil product candidate currently being developed for the treatment of sexual health conditions in both men and women.

The trial is designed to evaluate the safety, tolerability and pharmacokinetics of SST-6006 in healthy, post-menopausal women following a single dose applied topically to the vaginal tissue.

"This marks an important milestone for the treatment of FSAD, a significant unmet and under discussed need for many women."

The company said that a single centre, open-label, placebo-controlled, within-subject dose-escalation trial design will be used to assess three dose levels of SST-6006.

In the trial, safety evaluations will include physical examination, clinical laboratory evaluations, ECG, and adverse events.

In order to determine concentrations of sildenafil in plasma, pharmacokinetic analyses will be completed at pre-specified time points from pre-dose up to 32 hours post-dose.

In nonclinical and clinical studies conducted in healthy men, the topical application of SST-6006 has resulted in very low systemic absorption of sildenafil, compared to a comparable oral dose of sildenafil, providing the potential to reduce the side effects long associated with oral phosphodiesterase type-5 (PDE-5) inhibitors.

SST scientific founder and chief executive officer Eric Fossel said: "Based on the positive results in the Phase I trial in men, we are excited to begin our clinical evaluation of SST-6006 in women with FSAD. This marks an important milestone for the treatment of FSAD, a significant unmet and under discussed need for many women.

"With SST-6006’s novel topical delivery and potential review by the FDA as an over-the-counter product, we believe it could be a groundbreaking new therapy that positively impacts sexual health in both men and women."

The company aims to show that SST-6006 is a safe and effective treatment for women with FSAD, and intends to pursue potential registration of SST-6006 as an over-the-counter (OTC) topical product.

SST-6006 is developed using the company’s KNOSIS technology, a patented topical cream product containing 5% sildenafil citrate by weight.

Women of all ages are affected by FSAD, which is a disorder characterised by a persistent or recurrent inability to attain sexual arousal or to maintain arousal until the completion of a sexual activity.