Prostin E2 Description

PROSTIN E2 Vaginal Suppository, an oxytocic, contains dinoprostone as the naturally occurring prostaglandin E2 (PGE2).

Its chemical name is (5Z,11α,13E,15S)-11,15-Dihydroxy-9-oxo-prosta-5,13-dien-1-oic acid and the structural formula is represented below:

The molecular formula is C20H32O5. The molecular weight of dinoprostone is 352.5. Dinoprostone occurs as a white crystalline powder. It has a melting point within the range of 64° to 71°C. Dinoprostone is soluble in ethanol and in 25% ethanol in water. It is soluble in water to the extent of 130 mg/100 mL.

Each suppository contains 20 mg of dinoprostone in a mixture of glycerides of fatty acids.

Prostin E2 - Clinical Pharmacology

PROSTIN E2 Vaginal Suppository administered intravaginally stimulates the myometrium of the gravid uterus to contract in a manner that is similar to the contractions seen in the term uterus during labor. Whether or not this action results from a direct effect of dinoprostone on the myometrium has not been determined with certainty at this time. Nonetheless, the myometrial contractions induced by the vaginal administration of dinoprostone are sufficient to produce evacuation of the products of conception from the uterus in the majority of cases.

Dinoprostone is also capable of stimulating the smooth muscle of the gastrointestinal tract of man. This activity may be responsible for the vomiting and/or diarrhea that is not uncommon when dinoprostone is used to terminate pregnancy.

In laboratory animals, and also in man, large doses of dinoprostone can lower blood pressure, probably as a consequence of its effect on the smooth muscle of the vascular system. With the doses of dinoprostone used for terminating pregnancy this effect has not been clinically significant. In laboratory animals, and also in man, dinoprostone can elevate body temperature. With the clinical doses of dinoprostone used for the termination of pregnancy some patients do exhibit temperature increases.

Indications and Usage for Prostin E2

1. PROSTIN E2 Vaginal Suppository is indicated for the termination of pregnancy from the 12th through the 20th gestational week as calculated from the first day of the last normal menstrual period.
2. PROSTIN E2 is also indicated for evacuation of the uterine contents in the management of missed abortion or intrauterine fetal death up to 28 weeks of gestational age as calculated from the first day of the last normal menstrual period.
3. PROSTIN E2 is indicated in the management of nonmetastatic gestational trophoblastic disease (benign hydatidiform mole).

Contraindications

1. Hypersensitivity to dinoprostone [see WARNINGS and ADVERSE REACTIONS]
2. Acute pelvic inflammatory disease
3. Patients with active cardiac, pulmonary, renal, or hepatic disease

Precautions

Adverse Reactions/Side Effects

The most frequent adverse reactions observed with the use of dinoprostone for abortion are related to its contractile effect on smooth muscle.

In the patients studied, approximately two-thirds experienced vomiting, one-half temperature elevations, two-fifths diarrhea, one-third some nausea, one-tenth headache, and one-tenth shivering and chills.

In addition, approximately one-tenth of the patients studied exhibited transient diastolic blood pressure decreases of greater than 20 mmHg.

Two cases of myocardial infarction following the use of dinoprostone have been reported in patients with a history of cardiovascular disease.

It is not known whether these events were related to the administration of dinoprostone.

Adverse effects in decreasing order of their frequency, observed with the use of dinoprostone, not all of which are clearly drug related include:

Prostin E2 Dosage and Administration

STORE IN A FREEZER NOT ABOVE –20°C (–4°F) BUT BRING TO ROOM TEMPERATURE JUST PRIOR TO USE.

REMOVE FOIL BEFORE USE.

A suppository containing 20 mg of dinoprostone should be inserted high into the vagina. The patient should remain in the supine position for ten minutes following insertion. Additional intravaginal administration of each subsequent suppository should be at 3- to 5-hour intervals until abortion occurs. Within the above recommended intervals administration time should be determined by abortifacient progress, uterine contractility response, and by patient tolerance. Continuous administration of the drug for more than 2 days is not recommended.

How is Prostin E2 supplied

PROSTIN E2 Vaginal Suppositories are available in foil strips of 5 individually sealed suppositories, NDC 0009-0827-03. Each suppository contains 20 mg of dinoprostone in a mixture of glycerides of fatty acids.

This product's labeling may have been updated. For current full prescribing information, please visit www.pfizer.com

Rx only

LAB-0063-5.0
03/2017

PRINCIPAL DISPLAY PANEL - 20 mg Suppository Blister Pack

Prostin E2® 20 mg

(dinoprostone) vaginal suppository
Pharmacia & Upjohn Co., Division of Pfizer Inc, NY, NY 10017

LOT
EXP

PRINCIPAL DISPLAY PANEL - 20 mg Suppository Blister Pack Carton

NDC 0009-0827-03

5—20 mg Suppositories
Rx only

Prostin E2®
(dinoprostone) vaginal
suppository

20 mg

Pfizer Injectables