Daré Bioscience, Inc. announced the publication of data from a Phase 1 trial evaluating the pharmacokinetics of DARE-HRT1, an investigational intravaginal ring (IVR) designed to deliver bio-identical 17ß-estradiol and bio-identical progesterone continuously over a 28-day period as part of a hormone therapy regimen, in the journal Menopause, which is the journal of the North American Menopause Society. Daré previously reported positive topline results from this study, as well as from a subsequent Phase 1 /2 clinical trial of DARE-HRT1. Hormone therapy is used to treat the vasomotor symptoms (VMS) and genitourinary syndrome associated with menopause.

DARE-HRT1 has the potential to be the first FDA-approved product to offer vaginal delivery of combination bio-identical estradiol and bio-identical progesterone hormone therapy in a convenient monthly format. Daré plans to advance DARE-HRT1 into a single Phase 3 clinical trial to support a new drug application for DARE-HRT1 for the treatment of moderate to severe VMS due to menopause in women with intact uteri. The IVR technology used in DARE-HRT1 was developed by Dr. Robert Langer from the Massachusetts Institute of Technology and Dr. William Crowley from Massachusetts General Hospital and Harvard Medical School.

Unlike other IVR technologies, Daré's IVR drug delivery technology is designed to release more than one active ingredient via a solid ethylene vinyl acetate polymer matrix without the need for a membrane or reservoir to contain the active drug or to control the release, allowing for sustained drug delivery. Thirty-two (32) healthy postmenopausal women, with an average age of 57 years, were recruited at two Australian sites to participate in this open-label, three arm study. The first arm received one DARE-HTR1 ring for 28 days designed to release 17ß-estradiol (E2) at a rate of 80 µg/day and progesterone (P4) at 4mg/day.

The second arm received an alternative DARE-HRT1 ring for 28 days releasing E2 at 160 µg/day and P4 at 8mg/day. The third arm received both oral Estrofem (1mg E2) and Prometrium (100 mg P4) daily for 29 days. Blood samples were taken predose then intensively over the first day (day 1) and periodically thereafter over the remaining 27 days.

After removal of the DARE-HRT1 rings on the morning of day 29, intensive samples were collected. Similar procedures were conducted with women enrolled in the oral group. The plasma samples were analyzed for E2, estrone (E1), and P4 using validated bioanalytical methods.