Antares Pharma And Population Council Announce Preliminary Positive Phase 2 Trial Results

Main Category: Women's Health / Gynecology
Also Included In: Clinical Trials / Drug Trials
Article Date: 19 May 2009 - 5:00 PDT

email to a friend   printer friendly   opinions  

Antares Pharma, Inc. (NYSE Amex: AIS) and the Population Council announced preliminary positive results from the Phase 2 trial for a novel contraceptive gel containing the progestin Nestorone and the bio-identical estrogen estradiol (NES/E2) utilizing the Antares ATD (advanced transdermal delivery) gel system.

The trial is a dose finding, open-label, cross-over study to evaluate the effect of NES/E2 transdermal gel delivery on ovulation suppression in normal ovulating women. Eighteen women have participated in the trial, which is taking place in three sites: Los Angeles, California; Santo Domingo, Dominican Republic; and Santiago, Chile, and is scheduled to conclude active treatment in October 2009.

The preliminary data shows that all doses suppress ovulation. In addition, no serious adverse events have been recorded, and there have been no instances of skin irritation to date in the study.

Each woman in the study receives three separate doses of the gel for 21 days, separated by a washout month in which no products are administered. The primary objective of the study is to find the lowest acceptable dose of the NES/E2 gel to achieve appropriate therapeutic levels for effective contraception (ovulation suppression), as measured by progesterone levels and ultrasound evaluation of follicular development. Secondary objectives include determining the plasma profile of estradiol needed to reach estrogen replacement levels and to maintain regular bleeding patterns. General safety and tolerability of the NES/E2 gel, including any local skin irritation, is also being assessed.

This study follows on the successful completion of a Phase 1 study, which found an effective combined dose that consistently delivered Nestorone. In the Phase 1 study, serum levels, following multiple administrations, matched the target range expected to provide effective contraception. Blood levels for estradiol were also, on average, within the range for maintenance of a normal estrogenic environment and likely resulting in regular bleeding patterns.

Commenting on the progress of the current study, Regine Sitruk-Ware, executive director for research and development in the Reproductive Health Program of the Population Council, said, "We are encouraged by the preliminary results for this study. This is the first time these formulations have been used with ovulating women, and thus far they are meeting our expectations for both safety and efficacy."

Antares senior vice president and managing director of the pharmaceutical group Dario Carrara Ph.D., said, "We are very pleased with the progress of the study and that the interim results validate the product concept. A transdermal gel offers an excellent opportunity to provide safe and effective contraception through an innovative drug delivery system in a large and growing global market segment."

The National Survey of Family Growth has revealed that 31 percent of women discontinue use of reversible contraceptives for method-related reasons within six months of starting use, and 44 percent do so within 12 months. The novel NES/E2 transdermal gel offers a potentially attractive contraceptive option, in that both the formulation and the active compounds are designed to reduce the adverse events profile observed with current contraceptive methods and therefore could result in higher continuation rates by users. Worldwide contraception product sales in 2005 were $3.6 billion, with projections of approximately $4.5 billion by 2010, as reported by Thomson Pharma®.

Under the terms of a joint development agreement, Antares is responsible for research and development activities as they relate to ATD formulation and manufacturing, using the Population Council's patented and other proprietary information covering the compound. The Population Council is responsible for research on Nestorone and clinical trial design development and management. Together the parties expect to partner Nesterone with a worldwide or regional organization in order to commercialize it.

About Nestorone®

Nestorone is a fourth-generation synthetic progestin contraceptive derived from progesterone that has no androgenic hormonal effects and a good safety profile. It is not active when administered orally and is therefore especially appropriate for topical application as well as for use when breastfeeding.

About ATD™ Gel Technology

ATD™ Gel Technology is a hydroalcoholic transdermal gel containing less than 50 percent ethanol and a patented mixture of penetration enhancers. The matrix including Nestorone and bio-identical estradiol is designed to simultaneously deliver both drugs across the skin in a controlled and sustained fashion over a 24-hour period, and result in therapeutic plasma levels. The gel is crystal clear and cosmetically appealing, and dries readily after application to the abdomen, thighs, arms, or shoulders without leaving residues. Due to the low ethanol content, the gel is minimally irritating, as demonstrated by a similar FDA-approved formulation using ATD™ Gel Technology, ELESTRIN™ (low-dose estradiol for treating menopausal hot flashes).

Source
Antares Pharma

• Additional
• References
• Citations