Duavive - The Yellow Trail of Horse Pee Drugs Crosses the Pond to Europe
An Animal Rights Article from All-Creatures.org


Vivian Farrell and Jane Allin, Intl. Fund for Horses / Tuesday's Horse Blog
January 2015

The alleged duel-acting horse pee/bazedoxifene drug DUAVIVE—also known as DUAVEE in North America—has now made its way to the EU.

PMU foal
PMU (pregnant mare urine) foal

Its foundation drug Premarin, which alone and in combination, has been responsible for countless cancer deaths, has now crossed international boundaries.

How did this happen? Follow the trail.


Wyeth—gobbled up by, and now a Division of, pharmaceutical giant Pfizer—started working on Aprela in 1999 as a sister, or follow-up drug, to Premarin and its family of drugs that include Prempro and Premphase.

These drugs are produced with the estrogen rich urine of pregnant horses to treat the effects of menopause. The drugs also have osteoporosis treatment properties.

What’s the difference between Premarin and Aprela? A subtle one.

Pfizer began working with Ligand in 1991 as a research and development collaboration to develop better therapies for osteoporosis which eventually yielding the formulation of the drug Aprela.

Aprela is a single-pill formulation of conjugated [equine] estrogen and selective estrogen receptor modulator bazedoxifene.

Bazedoxifene is used instead of a progestin to help protect the uterine lining against hyperplasia that may result from estrogen alone treatment.

Wyeth had originally planned to file for FDA approval of Aprela in 2007, but the submission was repeatedly delayed. After the merger Pfizer eventually submitted Aprela on behalf of themselves and its partner Ligand to the FDA in 2012.


Aprela was finally approved under the name DUAVEE during the last U.S. federal government “shutdown”.

DUAVEE (conjugated [equine] estrogens/bazedoxifene), formerly known as APRELA, is a progesterone-free treatment for moderate-to-severe vasomotor symptoms (hot flashes) associated menopausal and the prevention of postmenopausal osteoporosis.

DUAVEE combines the selective estrogen receptor modulator (SERM) bazedoxifene with PREMARIN®.

In October, 2013, DUAVEE was approved by the U.S. FDA.

Additionally, in July 2012, Pfizer announced that the European Medicines Agency (EMA) accepted for review the Marketing Authorization Application (MAA) for bazedoxifene/conjugated estrogens. (see http://www.ligand.com/pfizer)

If you think DUAVEE is not as dangerous to patients as the Premarin family of drugs, look at this:

In the United States, Duavee is marketed with a black box warning. The warning points out that women taking Duavee should not take additional estrogens. The warning also notes that Duavee brings with it an increased risk for endometrial cancer in women with a uterus who use unopposed estrogens.
Also included in the black box warning is a reminder that estrogen therapy should not be used to prevent cardiovascular disease or dementia. In addition, the prescription insert warns that the Women’s Health Initiative estrogen-alone study reported an increased risk for stroke as well as an increased risk for deep vein thrombosis.


DUAVIVE is the European marketing name for DUAVEE.

Ligand issued a News Release that states:

Pfizer received EU marketing authorization for DUAVIVE® (conjugated estrogens/bazedoxifene (BZA/CE)) from the European Commission.

In the EU, DUAVIVE™ is indicated for the treatment of estrogen deficiency symptoms in postmenopausal women with a uterus (with at least 12 months since the last menses) for whom treatment with progestin-containing therapy is not appropriate.

Ligand will be entitled to a milestone payment following Pfizer obtaining pricing of DUAVIVE® in a major European market.(see http://goo.gl/STgib0)

This is tragic news for women and horses.

The Ligand News Release also states in its Forward Looking Statements section:

This news release contains forward looking statements by Ligand that involve risks and uncertainties and reflect Ligand’s judgment as of the date of this release. Actual events or results may differ from Ligand’s expectations. For example, there can be no assurance that conjugated estrogens/bazedoxifene or any product in the Ligand pipelines will be successfully developed, that any of the milestone triggers will be achieved, that regulatory approvals will be granted, that acceptable pricing will be achieved in a timely manner, that patient and physician acceptance of these products will be achieved, that final results of human clinical trials will be consistent with any interim results, that final results will be supportive of regulatory approvals required to market products or that any revenue will be achieved from this partnered program.

Jane Allin, Research Analyst for The Horse Fund, who has unparalleled specialist knowledge on this issue states:

In other words, take at your own risk. The Pfizer Ph-amily of carcinogens rules.

Don’t believe the FDA approval process or the EU’s. Don’t believe that this drug is safe and most of all, these are simply conjugated estrogens.

And what happened to the “equine” part of them? That they are made with pregnant mare’s urine?

In our opinion this clearly indicates that even more women are at risk to suffer and die. We know for certain from the decades long history of these drugs that the horses used to make them certainly will, and by numbers and in locations that will be close to impossible to discover.

Allin warns:

Will the slick deceptive marketing ploy convince countries outside of the US to accept this as the panacea to age-related menopausal symptoms and osteoporosis?

Until now, 92% of the sales of the Pfizer/Wyeth Premarin family of drugs has been apportioned to the United States.

How convenient to market the synergistic effects of a known carcinogen and a risky SERM in a pretty little propaganda package that combats the woes of being female—both here and abroad.

Unfortunately many will buy into it.

Horse urine kills—don’t be a statistic.

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