Kelnor 1/50

KELNOR 1/50- ethynodiol diacetate and ethinyl estradiol
Teva Pharmaceuticals USA, Inc.

Patients should be counseled that this product does not protect against HIV infection (AIDS) and other sexually transmitted diseases.

DESCRIPTION

Kelnor^® 1/50 (28 Day Regimen) (ethynodiol diacetate and ethinyl estradiol tablets USP). Each pink tablet contains 1 mg of ethynodiol diacetate, USP and 50 mcg of ethinyl estradiol, USP and the inactive ingredients include anhydrous lactose, magnesium stearate, microcrystalline cellulose, polacrilin potassium, and povidone. In addition, the coloring agents are D&C Red No. 30 Aluminum Lake and D&C Yellow No. 10 Aluminum Lake.

Each white tablet in the Kelnor 1/50 package is a placebo containing no active ingredients, and the inactive ingredients include anhydrous lactose, magnesium stearate and microcrystalline cellulose.

The chemical name for ethynodiol diacetate, USP is 19-nor-17α-pregn-4-en-20-yne-3β, 17-diol diacetate, and for ethinyl estradiol, USP it is 19-nor-17α-pregna-1, 3, 5 (10)-trien-20-yne-3, 17-diol. The structural formulas are as follows:

Ethynodiol Diacetate, USP

C₂₄ H₃₂ O₄ M.W. 384.51

Ethinyl Estradiol, USP

C₂₀ H₂₄ O₂ M.W. 296.40

Therapeutic class: Oral contraceptive.

CLINICAL PHARMACOLOGY

Combination oral contraceptives act primarily by suppression of gonadotropins. Although the primary mechanism of this action is inhibition of ovulation, other alterations in the genital tract, including changes in the cervical mucus (which increase the difficulty of sperm entry into the uterus) and the endometrium (which may reduce the likelihood of implantation) may also contribute to contraceptive effectiveness.

INDICATIONS AND USAGE

Kelnor 1/50 is indicated for the prevention of pregnancy in women who elect to use oral contraceptives as a method of contraception. Oral contraceptive products such as Kelnor 1/50, which contain 50 mcg of estrogen, should not be used unless medically indicated.

Oral contraceptives are highly effective. Table 1 lists the typical accidental pregnancy rates for users of combination oral contraceptives and other methods of contraception. The efficacy of these contraceptive methods, except sterilization and progestogen implants and injections, depends upon the reliability with which they are used. Correct and consistent use of methods can result in lower failure rates.

Table 1. Percentage of women experiencing an unintended pregnancy during the first year of typical use and the first year of perfect use of contraception and the percentage continuing use at the end of the first year. United States.

	% of women experiencing		% of women
	an unintended pregnancy		continuing
	within the first year of use		use at one
			year (C)
Method	Typical use (A)	Perfect use (B)
(1)	(2)	(3)	(4)
Chance (D)	85	85
Spermicides (E)	26	6	40
Periodic abstinence	25		63
Calendar		9
Ovulation method		3
Sympto-thermal (F)		2
Post-ovulation		1
Withdrawal	19	4
Cap (G)
Parous women	40	26	42
Nulliparous women	20	9	56
Sponge
Parous women	40	20	42
Nulliparous women	20	9	56
Diaphragm (G)	20	6	56
Condom (H)
Female (Reality)	21	5	56
Male	14	3	61
Pill	5		71
Progestin only		0.5
Combined		0.1
IUD
Progesterone T	2.0	1.5	81
Copper T 380A	0.8	0.6	78
LNg 20	0.1	0.1	81
Injection (Depo-Provera)	0.3	0.3	70
Implant (Norplant	0.05	0.05	88
and Norplant-2)
Female sterilization	0.5	0.5	100
Male sterilization	0.15	0.10	100
Emergency Contraceptive Pills: Treatment initiated within 72 hours after unprotected intercourse reduces the risk of pregnancy by at least 75%.(I)
Lactational Amenorrhea Method: LAM is a highly effective, temporary method of contraception.(J)
Source: Trussell J, Contraceptive efficacy. In Hatcher RA, Trussell J, Stewart F, Cates W, Stewart GK, Kowal D, Guest F, Contraceptive Technology: Seventeenth Revised Edition. New York NY: Irvington Publishers, 1998, in press.1 (A) Among typical couples who initiate use of a method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason. (B) Among couples who initiate use of a method (not necessarily for the first time) and who use it perfectly (both consistently and correctly), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason. (C) Among couples attempting to avoid pregnancy, the percentage who continue to use a method for one year. (D) The percents becoming pregnant in columns (2) and (3) are based on data from populations where contraception is not used and from women who cease using contraception in order to become pregnant. Among such populations, about 89% become pregnant within one year. This estimate was lowered slightly (to 85%) to represent the percent who would become pregnant within one year among women now relying on reversible methods of contraception if they abandoned contraception altogether. (E) Foams, creams, gels, vaginal suppositories, and vaginal film. (F) Cervical mucus (ovulation) method supplemented by calendar in the pre-ovulatory and basal body temperature in the post-ovulatory phases. (G) With spermicidal cream or jelly. (H) Without spermicides. (I) The treatment schedule is one dose within 72 hours after unprotected intercourse and a second dose 12 hours after the first dose. The Food and Drug Administration has declared the following brands of oral contraceptives to be safe and effective for emergency contraception: Ovral (1 dose is 2 white pills), Alesse (1 dose is 5 pink pills), Nordette or Levlen (1 dose is 2 light-orange pills), Lo/Ovral (1 dose is 4 white pills), Triphasil or Tri-Levlen (1 dose is 4 yellow pills). (J) However, to maintain effective protection against pregnancy, another method of contraception must be used as soon as menstruation resumes, the frequency or duration of breastfeeds is reduced, bottle feeds are introduced, or the baby reaches six months of age.