Ella (ulipristal acetate)

Ulipristal acetate, a synthetic selective progesterone receptor modulator, is a postcoital contraceptive.

Ulipristal acetate is a synthetic selective progesterone receptor modulator and a derivative of 19-norprogesterone. The drug is structurally and pharmacologically related to mifepristone. Ulipristal, like mifepristone, exhibits antagonist activity at progesterone receptors and inhibits progesterone from binding to its receptors; however, the drug also possesses partial agonist activity at the progesterone receptor.

Animal studies indicate that the antiglucocorticoid activity of ulipristal is lower than its antiprogestin activity. The exact mechanism of action of ulipristal is unknown, but may involve inhibition or delay of ovulation or inhibition of follicular growth or rupture; alterations to the endometrium that may affect implantation also may contribute to efficacy. However, in doses used for postcoital contraception (30 mg), ulipristal acetate has no clinically important effect on the endometrium.

Peak plasma concentrations of ulipristal acetate and its active metabolite, monodemethyl ulipristal acetate, are reached 60-90 minutes following a single oral dose under fasting conditions. Administration of ulipristal with a high-fat meal reduced mean peak plasma concentrations by 40-45% and delayed the time to peak plasma concentration from a median of 0.75 to 3 hours. However, the differences resulting from administration of the drug with food are not expected to result in clinically important effects on efficacy or safety.

Ulipristal acetate is more than 94% bound to plasma proteins, mainly high density lipoprotein (HDL)-cholesterol, alpha-1-acid glycoprotein, and albumin. In vitro data show that ulipristal is metabolized mainly by the cytochrome P-450 (CYP) 3A4 isoenzyme to mono-demethylated and di-demethylated metabolites. The terminal half-life of ulipristal acetate is approximately 32 hours following oral administration.

USES: Ulipristal is used by women to prevent pregnancy after birth control failure (such as a broken condom) or unprotected sex. This medication is an emergency contraceptive and should not be used as a regular form of birth control. Using this medication will not stop an existing pregnancy or protect you or your partner against sexually transmitted diseases (such as HIV, gonorrhea, chlamydia).

This medication may not work well in women who are overweight (for example, body mass index greater than 30) or if you are using certain other medications. This effect can result in pregnancy. Talk to your doctor for more details and to see if this medication is right for you (see also Drug Interactions section).

Generic name: ulipristal acetate
Pronunciation: (UE-li-PRIS-tal)

The following indications are listed for Ella:

• Postcoital Contraception

Also known as: Emergency Contraception.

No ICD codes are available for this drug.