Arletta Pharma's Lybrido™ Shows Statistically Significant Improvement in Female Sexual Dysfunction Phase II Trial
Key Insights
Arletta Pharma Solutions (search) reported positive Phase II results for Lybrido™, showing more than 60% average improvement in clitoral blood flow in women with Female Sexual Interest/Arousal Disorder (search).
The high-dose combination of testosterone and sildenafil achieved statistical significance (p=0.008) despite a small sample size of 16 premenopausal women.
The study validates dose selection for upcoming pivotal trials and represents the first objective biomarker evidence for the high-dose formulation in FSIAD (search) patients.
Arletta Pharma Solutions (search) announced compelling positive results from its Phase II Clitoral Doppler Duplex Ultrasound study evaluating Lybrido™, a combination therapy of testosterone and sildenafil, in women with Female Sexual Interest/Arousal Disorder (search) (FSIAD (search)). The study successfully achieved its primary endpoint, demonstrating objective physiological evidence of arousal response and confirming optimal dose selection for continued clinical development.
The investigator-initiated study, conducted at Chaim Sheba Medical Center (search) under Principal Investigator Prof. Cobi Reisman and Co-Investigator Dr. Anna Padoa, evaluated two dose-combinations of Lybrido™ in premenopausal women diagnosed with acquired generalized FSIAD (search). The study utilized standardized Clitoral Doppler Duplex Ultrasound to quantify clitoral blood flow parameters, serving as a key biomarker of genital arousal.
Robust Efficacy Signal Achieved
Both dose-combinations demonstrated more than 60% average improvement in Peak Systolic Velocity (PSV), the primary measure of clitoral blood flow. The high-dose combination (Testosterone 1.0 mg + Sildenafil 100 mg) achieved statistical significance (p=0.008), demonstrating a clear and consistent physiological arousal response despite the relatively small sample size of 16 participants.
"These results represent a watershed moment for Arletta Pharma's clinical development program," said Nicole Hijnen, Chief Executive Officer of Arletta Pharma Solutions (search). "For the first time, we have objective biomarker evidence demonstrating that our high-dose Lybrido™ formulation produces statistically significant physiological arousal responses in women with FSIAD (search), even with a small sample size."
Prof. Cobi Reisman, the study's Principal Investigator, commented that the results "offer physiological evidence suggesting that combination therapy with sublingual testosterone and oral sildenafil may produce notable improvements in clitoral blood flow, which can serve as an indicator of genital arousal capacity."
Study Design and Mechanism Validation
The randomized, open-label Phase II dose-response study enrolled 16 premenopausal women with acquired generalized FSIAD (search). Participants were randomized to receive either the standard dose-combination or the high dose-combination of testosterone plus sildenafil. The primary outcome measure was change from baseline in Peak Systolic Velocity of clitoral blood flow measured by Clitoral Doppler Duplex Ultrasound.
The results are consistent with Lybrido™'s known mechanism of action regarding phosphodiesterase 5 (search) (PDE5 (search)) inhibition's enhancement of genital blood flow. Previous research by van der Made, Bloemers et al. (2009) established that testosterone enhances the effect of PDE-5 inhibitors on genital blood flow in women with Hypoactive Sexual Desire Disorder (search), with combination therapy showing significantly superior results compared to either component alone (p<0.03).
Addressing Significant Unmet Medical Need
Female Sexual Interest/Arousal Disorder (search), as defined in the DSM-5, is characterized by persistent reductions in both sexual interest and/or arousal. FSIAD (search) is diagnosed when symptoms persist for a minimum of six months and cause clinically significant distress. An estimated 8% of adult women meet diagnostic criteria for FSIAD, representing approximately 250 million women worldwide.
Among female sexual disorders, low sexual desire and arousal consistently represent the most common issues affecting women, often leading to clinically significant distress, dissatisfaction in intimate relationships, and profoundly impacting emotional well-being and quality of life.
Innovative Dual-Action Therapy
Lybrido™ is an investigational on-demand, dual-action therapy designed to address both the psychological and physiological components of FSIAD (search) and Hypoactive Sexual Desire Disorder (search). The treatment consists of a novel dual-route, dual-release, fixed dose-combination tablet with a testosterone coating for sublingual administration and an inner-core component containing the PDE5 (search) inhibitor sildenafil.
The proprietary delayed-immediate-release formulation ensures that peak plasma concentration of sildenafil coincides with the window of increased sexual motivation induced by sublingually administered testosterone. This synchronized dual mechanism enables increased genital arousal through enhanced responsivity to sexual stimuli, with effects lasting 3 to 6 hours after intake.
Clinical Development Program Advancement
To date, Lybrido™ has been investigated in 20 Phase I and Phase IIa trials, plus large-scale Phase IIb trials conducted across 17 US research sites, establishing a substantial safety and efficacy database. The therapy addresses both central sexual motivation and peripheral genital arousal, representing a differentiated mechanism of action compared to currently available treatments.
In parallel with the planned pivotal study in Europe, Arletta Pharma is evaluating the initiation of a smaller Phase II study in the United States, focusing on the highest Lybrido™ dose-combination identified in the CDU study (1.0 mg Testosterone / 100 mg Sildenafil). The US Phase II trial is designed to further characterize the efficacy and safety profile of the high-dose regimen in the target population of women suffering from FSIAD (search).