Dare Bioscience Inc (NASDAQ:DARE) is a mover and shaker out on the Street today, with investors sparking the stock on an almost 17% upturn. Why the excitement? The women’s health firm announced that it has entered into a merger agreement with Pear Tree Pharmaceuticals to secure the rights to develop PT-101, a proprietary vaginal formulation of tamoxifen, as a potential treatment for vulvar and vaginal atrophy (VVA) in patients with hormone-receptor-positive breast cancer, including estrogen receptor-positive (ER-positive) and progesterone receptor-positive (PR-positive) breast cancer.
Oral tamoxifen is already approved by the FDA as a treatment for hormone-receptor-positive breast cancer. PT-101 incorporates the active ingredient tamoxifen in a tablet formulation designed to deliver the drug vaginally.
VVA is a chronic condition characterized by pain during intercourse, vaginal dryness and irritation brought on from reduced estrogen levels. For many women, first-line treatments typically include localized estrogen therapy. However, this therapeutic approach is often contraindicated for more than two million women diagnosed with, or at risk of recurrence of, ER-positive and PR-positive breast cancer. Daré intends to develop this novel local application of tamoxifen to mitigate the symptoms of VVA for patients with or at risk for hormone-receptor-positive breast cancer, including women currently on anti-cancer therapy.
If approved, PT-101 has the potential to be the first treatment specifically developed for VVA in patients with hormone-receptor positive breast cancer.
“Adding vaginal tamoxifen to our innovative portfolio of novel women’s health products aligns perfectly with our mission of meaningfully impacting women’s lives by identifying and advancing products that address therapeutic gaps in contraception, sexual health and vaginal health,” said Sabrina Martucci Johnson, President and CEO, Daré Bioscience. “We are optimistic about the potential for this clinical candidate to become the first VVA therapy designed explicitly for hormone-receptor-positive breast cancer patients.”
Approximately 10 percent of women in the U.S. will develop breast cancer. The prevalence of VVA in postmenopausal breast cancer patients is reported to be between 42 and 70 percent. Daré believes there is a large unmet need for a novel non-hormonal VVA treatment specifically developed for this subset of cancer patients and survivors.
“There is a need to find a safe and efficacious way to treat vulvar and vaginal atrophy (VVA) in women who have hormone receptor positive breast cancer,” commented Dr. Shari Goldfarb, assistant attending physician at the Memorial Sloan Kettering Cancer Center. There are currently no FDA approved treatments that have been specifically developed for use in this population, despite the significant proportion of hormone-receptor positive patients who develop VVA.”
PT-101 has been evaluated in four subjects in a proof-of-concept human study where it was shown to improve vaginal dryness and decrease vaginal pH. In 2018 Daré plans to optimize the vaginal formulation before initiating additional clinical work.
The closing of the merger with Pear Tree is subject to a number of conditions, including approval of the merger by Pear Tree’s stockholders. Upon the closing of the merger transaction, PT-101 will be incorporated into to Daré’s growing portfolio of novel clinical-stage therapeutic candidates that address unmet needs in women’s reproductive health. The pipeline currently includes Ovaprene™, a non-hormonal, monthly contraceptive ring in pre-pivotal studies, and topical sildenafil, a potential treatment for female sexual arousal disorder that is in Phase 2 development.