Aromatase inhibitors have been proven to fight breast cancer, but start-up Meditrina Pharmaceuticals Inc. thinks they also may be able to treat a variety of women's health conditions.

The Ann Arbor, Mich.-based company was founded in 2006 on the back of intellectual property licensed from Wayne State University and Mount Sinai Hospital in Toronto covering the use of aromatase inhibitors in pre-ablation endometrial thinning and ectopic pregnancy. Meditrina, named for the Roman goddess of health and wine, has used its patent portfolio to attract seed funding, build a six-person team and jump into a Phase II trial.

Three aromatase inhibitors are already FDA-approved: Arimidex (anastrazole, AstraZeneca plc), Aromasin (exemestane, Pfizer Inc.) and Femara (letrozole, Novartis AG). They treat breast cancer by decreasing the production of estrogen in the adrenal and other tissues of postmenopausal women whose ovaries already have stopped producing the hormone.

Meditrina cofounder, President and CEO Thomas Collet said the "enzymology is the same" in premenopausal women, even though their ovaries still are producing estrogen. The company plans to use a higher-dose aromatase inhibitor to target premenopausal women, and Collet noted that Meditrina's drugs will be formulated as capsules rather than tablets.

Although all three approved aromatase inhibitors are branded products, Collet said their composition-of-matter patents will expire by the time Meditrina's drugs hit the market via a 505(b)(2) approval pathway. Co-founder and Chief Operating Officer Holly Vene added that the company's initial research indicated insurers would be willing to cover Meditrina's products as long as they are "priced competitively," and noted that they "will not be A-B substitutable" with the existing aromatase inhibitors.

Earlier this year, Meditrina began a Phase II trial of an aromatase inhibitor dubbed Femathina for thinning of the endometrial lining prior to ablation in the treatment of abnormal uterine bleeding.

About 2.4 million patient visits to OB/GYNs each year can be attributed to abnormal bleeding, Vene said, and the 50 percent who don't respond to drugs undergo either a hysterectomy or endometrial ablation. Four out of the five devices approved for ablation require endometrial thinning first, which is achieved with Gonadotropin-Releasing Hormone (GnRH) agonists.

But the GnRH agonists must be injected and are "difficult to tolerate because they put women into a state similar to postmenopause that lasts one to two months," Vene said. Meditrina hopes to provide an oral, better-tolerated option.

The Phase II trial is evaluating the ability of Femathina to affect estradiol levels and endometrial thinning at different points in the menstrual cycle of healthy volunteers, and data are expected before the end of the year. If successful, Meditrina plans to proceed to a second Phase II trial and then a Phase III.

Collet said the endometrial thinning market could generate about $200 million in peak U.S. annual sales.

Meditrina also plans to evaluate other doses of aromatase inhibitors in women's health indications such as endometriosis, uterine fibroids and ectopic pregnancy and has begun to expand its patent portfolio accordingly.

Collet estimated that endometriosis could generate $550 million to $600 million annually, with uterine fibroids bringing in $250 million to $500 million and ectopic pregnancy bringing in less than $100 million.

In preparation for its next round of trials, Meditrina is kicking its Series A fundraising process "into high gear," Collet said. The company previously raised $4.4 million in seed money and hopes to close the Series A early next year. Seed investors included the 21st Century Jobs Fund administered by the Michigan Economic Development Corp. and the Biosciences Research and Commercialization Center at Western Michigan University.

As of now, Meditrina holds all rights to its products. Vene said the company plans to seek partners for ex-U.S. rights after Phase II but will hold on to U.S. rights through registration and then decide whether to go it alone or seek a partner.