General Information

Crinone (progesterone gel) is a bioadhesive vaginal gel containing micronized progesterone in an emulsion system, which is contained in single use, polypropylene vaginal applicators.

Crinone 8% is indicated for progesterone supplementation or replacement as part of an Assisted Reproductive Technology ("ART") treatment for infertile women with progesterone deficiency.

Crinone 4% is indicated for the treatment of secondary amenorrhea. Crinone 8% is indicated for use in women who have failed to respond to treatment with Crinone 4%.

The recommended dosage/administration is as follows:

Assisted Reproductive Technology

• Crinone 8% is administered vaginally at a dose of 90 mg once daily in women who require progesterone supplementation. Crinone 8% is administered vaginally at a dose of 90 mg twice daily in women with partial or complete ovarian failure who require progesterone replacement. If pregnancy occurs, treatment may be continued until placental autonomy is achieved, up to 10 to 12 weeks.

Secondary Amenorrhea

• Crinone 4% is administered vaginally every other day up to a total of six doses. For women who fail to respond, a trial of Crinone 8% every other day up to a total of six doses may be instituted. It is important to note that a dosage increase from the 4% gel can only be accomplished by using the 8% gel. Increasing the volume of gel administered does not increase the amount of progesterone absorbed.

Mechanism of Action

Progesterone is a naturally occurring steroid that is secreted by the ovary, placenta, and adrenal gland. In the presence of adequate estrogen, progesterone transforms a proliferative endometrium into a secretory endometrium. Progesterone is essential for the development of decidual tissue, and the effect of progesterone on the differentiation of glandular epithelia and stroma has been extensively studied. Progesterone is necessary to increase endometrial receptivity for implantation of an embryo. Once an embryo is implanted, progesterone acts to maintain the pregnancy. Normal or near-normal endometrial responses to oral estradiol and intramuscular progesterone have been noted in functionally agonadal women through the sixth decade of life. Progesterone administration decreases the circulatory levels of gonadotropins.

Clinical Trial Results

ART Therapy

In a progesterone replacement clinical study, women requiring progesterone replacement were administered Crinone 8% at a dose of one applicator (90mg) twice daily. Of the 54 women who underwent an embryo transfer and were treated with crinone, 48% achieved a clinical pregnancy, and 31% delivered.

In a progesterone supplement clinical study, women requiring progesterone supplementation were evaluated following an in-vitro fertilization procedure. In this study, patients received one applicator (90mg) of crinone once daily. Of the 139 patients who received an embryo, 26% achieved a clinical pregnancy and 23% delivered.

Amenorrhea

In three parallel, open-label studies, 127 women (aged 18-44) with hypothalamic amenorrhea or premature ovarian failure were randomized to receive either Crinone 4% (n = 62) or Crinone 8% (n = 65). All women were treated with either conjugated estrogens 0.625 mg daily (n = 100) or transdermal estradiol (delivering 50 mcg/day) twice weekly (n = 27). Estrogen therapy was continuous for the entire three 28-day cycle studies. At Day 15 of the second cycle (six weeks after initiating estrogen replacement), women who demonstrated adequate response to estrogen therapy (by ultrasound) and who continued to be amenorrheic received Crinone every other day for six doses (Day 15 through Day 25 of the cycle). In cycle 2, Crinone 4% induced bleeding in 79% of women and Crinone 8% induced bleeding in 77% of women. In the third cycle, estrogen was continued and Crinone was administered every other day beginning on Day 15 for six doses. On Day 24 an endometrial biopsy was performed. In 53 women who received Crinone 4%, biopsy results were as follows: 7% proliferative, 40% late secretory, 19% mid secretory, 13% early secretory, 7% atrophic, 6% menstrual endometrium, 6% inactive endometrium and 2% negative endometrium. In 54 women who received Crinone 8%, biopsy results were as follows: 44% late secretory, 19% mid secretory, 11% early secretory, 19% atrophic, 5% menstrual endometrium and 2% "oral contraceptive like" endometrium.