Evofem Biosciences Secures Patent Protection for SOLOSEC Through 2041, Strengthening Market Position for Single-Dose STI Treatment
Key Insights
Evofem Biosciences announced that a new U.S. patent covering SOLOSEC (secnidazole) for trichomoniasis (search) treatment has been listed in the FDA Orange Book, extending market exclusivity until December 2041.
The company now holds eleven Orange Book-listed patents for SOLOSEC, the first and only single-dose oral treatment FDA-approved for both bacterial vaginosis (search) and trichomoniasis (search) in the United States.
An ongoing NIH-funded Phase 4 clinical trial is evaluating SOLOSEC's effectiveness versus metronidazole, with investigators hypothesizing 1.75 times lower repeat infection rates with the single-dose regimen.
Evofem Biosciences announced that a newly-issued U.S. patent covering SOLOSEC (secnidazole) 2g oral granules for trichomoniasis (search) treatment has been listed in the FDA Orange Book, significantly strengthening the company's intellectual property portfolio and extending market exclusivity through December 2041.
Patent Portfolio Expansion
The newly listed U.S. Patent No. 12,280,037 covers "method and pharmaceutical composition for treating or preventing trichomoniasis (search) and uses thereof." Issued by the U.S. Patent and Trademark Office on April 22, 2025, the patent focuses on treatment of Trichomonas vaginalis (search) infections with broad claims centered on pharmacokinetics and formulation features of Evofem's single-dose oral antimicrobial agent.
"The Orange Book listing of this patent covering SOLOSEC's method, pharmaceutical composition, and use in trichomoniasis (search) is an important step in further strengthening our patent portfolio," said Evofem Biosciences CEO Saundra Pelletier. "The patent itself extends SOLOSEC's intellectual property and market exclusivity into December 2041, which significantly benefits prescribers, patients, and our investors with a longer opportunity to build the SOLOSEC brand – the first and only single-dose oral treatment FDA-approved to treat BV as well as trichomoniasis – in the U.S."
With this addition, Evofem now holds eleven Orange Book-listed patents covering SOLOSEC into late 2041, providing substantial protection for the company's flagship antimicrobial product.
Clinical Significance and Market Impact
Trichomoniasis (search) represents the most common non-viral sexually transmitted infection globally, with an estimated 6.9 million new infections with T. vaginalis occurring in the U.S. each year. The condition presents significant treatment challenges, as undiagnosed infections and lack of compliance with multi-day treatment regimens are critical contributing factors to its persistence.
SOLOSEC addresses these challenges through its single-dose formulation, designed to provide a complete course of treatment in one oral dose. All sexual partners of people infected with trichomoniasis (search) should be treated with the same dose simultaneously to prevent reinfection, making the convenience of single-dose therapy particularly valuable.
Ongoing Clinical Research
Patient recruitment is currently underway in an investigator-led, NIH-funded Phase 4 clinical trial evaluating the effectiveness and cost-effectiveness of SOLOSEC versus metronidazole for T. vaginalis treatment in both men and women. The study compares single-dose SOLOSEC against the standard twice-daily metronidazole regimen administered for seven days.
Study investigators hypothesize that the rate of repeat infections with T. vaginalis will be 1.75 times lower in the SOLOSEC arm compared to the multi-dose oral metronidazole arm. Additionally, researchers expect that while single-dose SOLOSEC will have higher initial cost, it will prove more cost-effective compared to multi-dose metronidazole, largely due to lower breakthrough rates of infection.
Product Portfolio and Regulatory Status
SOLOSEC (secnidazole) 2g oral granules is FDA-approved as an oral antibiotic for treating two sexual health conditions: bacterial vaginosis (search) in females 12 years of age and older, and trichomoniasis (search) in people 12 years of age and older. The drug provides a complete course of therapy in a single dose, distinguishing it from traditional multi-day treatment regimens.
Evofem also commercializes PHEXXI (lactic acid, citric acid, and potassium bitartrate), the first and only hormone-free, on-demand prescription contraceptive vaginal gel. The company generates revenue from both FDA-approved products as part of its focus on addressing unmet needs in women's sexual and reproductive health.
Corporate Developments
Evofem filed a preliminary proxy on July 24, 2025, regarding its planned Special Meeting of Stockholders. Shareholders will vote on a proposal to approve transactions under an Amended and Restated Merger Agreement between Evofem, Aditxt, Inc., and Adifem, Inc. Under the agreement, Adifem will merge with Evofem, with Evofem surviving as a wholly owned subsidiary of Aditxt. A definitive proxy filing is expected in the coming weeks.