EMCYT- estramustine phosphate sodium capsule

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

ESTRAMUSTINE PHOSPHATE SODIUM (UNII: 75F375MT2N) (ESTRAMUSTINE - UNII:35LT29625A)

Available from:

Pfizer Laboratories Div Pfizer Inc

INN (International Name):

ESTRAMUSTINE PHOSPHATE SODIUM

Composition:

ESTRAMUSTINE PHOSPHATE 140 mg

Administration route:

ORAL

Prescription type:

PRESCRIPTION DRUG

Therapeutic indications:

EMCYT Capsules are indicated in the palliative treatment of patients with metastatic and/or progressive carcinoma of the prostate. EMCYT Capsules should not be used in patients with any of the following conditions:

Product summary:

White opaque capsules, each containing estramustine phosphate sodium as the disodium salt monohydrate equivalent to 140 mg estramustine phosphate—bottle of 100 (NDC 0013-0132-02). NOTE EMCYT Capsules should be stored in the refrigerator at 36° to 46°F (2° to 8°C).

Authorization status:

New Drug Application

Summary of Product characteristics

EMCYT- ESTRAMUSTINE PHOSPHATE SODIUM CAPSULE
PFIZER LABORATORIES DIV PFIZER INC
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EMCYT
ESTRAMUSTINE PHOSPHATE SODIUM
CAPSULES
DESCRIPTION
Estramustine phosphate sodium, an antineoplastic agent, is an
off-white powder readily soluble in water.
EMCYT Capsules are white and opaque, each containing estramustine
phosphate sodium as the disodium salt
monohydrate equivalent to 140 mg estramustine phosphate, for oral
administration. Each capsule also
contains magnesium stearate, silicon dioxide, sodium lauryl sulfate,
and talc. Gelatin capsule shells contain
the following pigment: titanium dioxide.
Chemically, estramustine phosphate sodium is
estra-1,3,5(10)-triene-3,17-diol(17β)-,3-[bis(2-
chloroethyl)carbamate] 17-(dihydrogen phosphate), disodium salt,
monohydrate. It is also referred to as
estradiol 3-[bis(2-chloroethyl)carbamate] 17-(dihydrogen phosphate),
disodium salt, monohydrate.
Estramustine phosphate sodium has an empiric formula of C
H
Cl
NNa O P•H O, a calculated molecular
weight of 582.4, and the following structural formula:
CLINICAL PHARMACOLOGY
Estramustine phosphate (Figure 1) is a molecule combining estradiol
and nornitrogen mustard by a carbamate
link. The molecule is phosphorylated to make it water soluble.
Estramustine phosphate taken orally is readily dephosphorylated during
absorption, and the major
metabolites in plasma are estramustine (Figure 2), the estrone analog
(Figure 3), estradiol, and estrone.
Prolonged treatment with estramustine phosphate produces elevated
total plasma concentrations of estradiol
that fall within ranges similar to the elevated estradiol levels found
in prostatic cancer patients given
conventional estradiol therapy. Estrogenic effects, as demonstrated by
changes in circulating levels of steroids
and pituitary hormones, are similar in patients treated with either
estramustine phosphate or conventional
estradiol.
The metabolic urinary patterns of the estradiol moiety of estramustine
phosphate and estradiol itself are very
similar, although the metabolites deri