5.1 Existing Pregnancy

ella is not indicated for termination of an existing pregnancy

5.2 Ectopic Pregnancy

A history of ectopic pregnancy is not a contraindication to use of this emergency contraceptive method.  Healthcare providers, however, should consider the possibility of ectopic pregnancy in women who become pregnant or complain of lower abdominal pain after taking ella.  A follow-up physical or pelvic examination is recommended if there is any doubt concerning the general health or pregnancy status of any woman after taking ella.

5.3 Repeated Use

ella is for occasional use as an emergency contraceptive. It should not replace a regular method of contraception. Repeated use of ella within the same menstrual cycle is not recommended, as safety and efficacy of repeat use within the same cycle has not been evaluated.

5.4 CYP3A4 Inducers

A CYP3A4 inducer, rifampin, decreases the plasma concentration of ella significantly. ella should not be administered with CYP3A4 inducers [see Drug interactions (7.1) and Clinical Pharmacology (12.3)].

5.5 Fertility Following Use

A rapid return of fertility is likely following treatment with ella for emergency contraception.

After use of ella, a reliable barrier method of contraception should be used with subsequent acts of intercourse that occur in that same menstrual cycle.
Because ella and the progestin component of hormonal contraceptives both bind to the progesterone receptor, using them together could reduce their contraceptive effect. After using ella, if a woman wishes to use hormonal contraception, she should do so no sooner than 5 days after the intake of ella, and she should use a reliable barrier method until the next menstrual period [see Drug Interactions (7.1 and 7.3) and Clinical Pharmacology (12.2)].

5.6 Effect on Menstrual Cycle

After ella intake, menses sometimes occur earlier or later than expected by a few days. In clinical trials, cycle length was increased by a mean of 2.5 days but returned to normal in the subsequent cycle. Seven percent of subjects reported menses occurring more than 7 days earlier than expected, and 19% reported a delay of more than 7 days. If there is a delay in the onset of expected menses beyond 1 week, rule out pregnancy.

Nine percent of women studied reported intermenstrual bleeding after use of ella.

5.7 Sexually Transmitted Infections/HIV

ella does not protect against HIV infection (AIDS) or other sexually transmitted infections (STIs).

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

ella was studied in an open-label multicenter trial (Open-Label Study) and in a comparative, randomized, single-blind, multicenter trial (Single-Blind Comparative Study). In these studies, a total of 2,637 (1,533 + 1,104) women in the 30 mg ulipristal acetate groups were included in the safety analysis. The mean age of women who received ulipristal acetate was 24.5 years and the mean body mass index (BMI) was 25.3. The racial demographics of those enrolled were 67% Caucasian, 20% Black or African American, 2% Asian, and 12% other. 

The most common adverse reactions (≥ 10%) in the clinical trials for women receiving ella were headache (18% overall) and nausea (12% overall) and abdominal and upper abdominal pain (12% overall). Table 1 lists those adverse reactions that were reported in ≥ 5% of subjects in the clinical studies (14).

6.2 Postmarketing Experience

Adolescents: the safety profile observed in adolescents aged 17 and younger in studies and post-marketing is similar to the safety profile in adults [see Pediatric Use (8.4)].

The following adverse reactions have been identified during post-approval use of ella:        Skin and Subcutaneous Tissue Disorders: Acne

Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

7.1 Changes in Emergency Contraceptive Effectiveness Associated with Co-Administration of Other Products

Drugs or herbal products that induce CYP3A4 decrease the plasma concentrations of ella, and may decrease its effectiveness [see Warnings and Precautions (5.4) and Pharmacokinetics (12.3)]. Avoid co-administration of ella and drugs or herbal products such as:

• barbiturates
• bosentan
• carbamazepine
• felbamate
• griseofulvin
• oxcarbazepine
• phenytoin
• rifampin
• St. John's Wort
• topiramate

Hormonal contraceptives: Progestin-containing contraceptives may impair the ability of ella to delay ovulation [see Warnings and Precautions (5.5) and Pharmacodynamics (12.2)]. Avoid co-administration of ella and hormonal contraceptives. If a woman wishes to start or resume hormonal contraception after the intake of ella, she should do so no sooner than 5 days afterwards, and she should use a reliable barrier method until the next menstrual period.

7.2 Increase in Plasma Concentrations of ella Associated with Co-Administered Drugs

CYP3A4 inhibitors such as itraconazole or ketoconazole increase plasma concentrations of ella [see Pharmacokinetics (12.3)].

7.3 Effects of ella on Co-Administered Drugs

Hormonal contraceptives: ella may impact the effect of the progestin component of hormonal contraceptives. Therefore, if a woman wishes to use hormonal contraception after using ella, she should use a reliable barrier method for subsequent acts of intercourse until her next menstrual period [see Warnings and Precautions (5.5) and Clincial Pharmacology(12.2)].

8.1 Pregnancy

8.2 Lactation

8.3 Females and Males of Reproductive Potential

8.4 Pediatric Use

Safety and efficacy of ella have been established in women of reproductive age.  The clinical trials of ella enrolled 41 females under age 18, and a post-marketing observational study evaluating effectiveness and safety of ella in adolescents enrolled 279 females under age 18, including 76 under age 16 years.   In these studies, the safety and efficacy profile observed in adolescents aged 17 and younger was similar to that in adults.  Use of ella before menarche is not indicated.

8.5 Geriatric Use

This product is not intended for use in postmenopausal women.

8.6 Race

While no formal studies have evaluated the effect of race, a cross-study comparison of two pharmacokinetic studies indicated that exposure in South Asians may exceed that in Caucasians and African Americans. However, no difference in efficacy and safety was observed for women of different races in clinical studies.

8.7 Hepatic Impairment

No studies have been conducted to evaluate the effect of hepatic disease on the disposition of ella.

8.8 Renal Impairment

No studies have been conducted to evaluate the effect of renal disease on the disposition of ella.

12.1 Mechanism of Action

When taken immediately before ovulation is to occur, ella postpones follicular rupture. The likely primary mechanism of action of ulipristal acetate for emergency contraception is therefore inhibition or delay of ovulation; however, alterations to the endometrium that may affect implantation may also contribute to efficacy. 

12.2 Pharmacodynamics

Ulipristal acetate is a selective progesterone receptor modulator with antagonistic and partial agonistic effects (a progesterone agonist/antagonist) at the progesterone receptor. It binds the human progesterone receptor and prevents progesterone from occupying its receptor.

The pharmacodynamics of ulipristal acetate depends on the timing of administration in the menstrual cycle. Administration in the mid-follicular phase causes inhibition of folliculogenesis and reduction of estradiol concentration.  

Pharmacodynamic data showed that administration of ella to 34 women in the late follicular phase postponed follicular rupture for at least 5 days in all (100%) of 8 subjects who took ella before the luteinizing hormone (LH) surge and 11 (79%) of 14 subjects who took ella immediately before ovulation (when LH has already started to rise).  However, treatment was not effective in postponing follicular rupture when administered on the day of LH peak.

Dosing in the early luteal phase does not significantly delay endometrial maturation but decreases endometrial thickness by 0.6 ± 2.2 mm (mean ± SD).

Hormonal Contraceptives after ella intake:

When a combined oral contraceptive pill (COC) containing ethinyl estradiol 30 µg + levonorgestrel 150 µg  was started the day after ella intake during the follicular phase, ella did not interfere with the COC's ability to suppress ovarian activity, as assessed by measurement of follicle size via transvaginal ultrasound, combined with serum progesterone and estradiol levels: ovarian activity was suppressed in 61.5% (24/39) of subjects receiving ella plus COC and 62.2% (23/37) of  subjects receiving a placebo plus the COC. The incidence of ovulation was similar between the group who received ella plus the COC [33.3% (13/39)]  and the group who received a placebo plus the COC [32.4% (12/37)]. [see Warnings and Precautions (5.5) and Drug Interactions (7.3)].

The initiation of a desogestrel 75 µg "progestin-only pill" the day after ella intake during the follicular phase was associated with a higher incidence of ovulation in the six days following ella intake compared to an ella-only treatment group, and a relatively slower onset (3 to 4 days) of thickened cervical mucus compared to a group given desogestrel without prior ella intake (2 days), suggesting an effect of prior use of ella on the ability of desogestrel to inhibit mucus permeability. [See Warnings and Precautions (5.5) and Drug Interactions (7.1; 7.3)].

12.3 Pharmacokinetics

Absorption

Following a single dose administration of ella in 20 women under fasting conditions, maximum plasma concentrations of ulipristal acetate and the active metabolite, monodemethyl-ulipristal acetate, were 176 and 69 ng/ml and were reached at 0.9 and 1 hour, respectively. 

Figure 1: Mean (± SD) Plasma Concentration-time Profile of Ulipristal Acetate and Monodemethyl-ulipristal Acetate Following Single Dose Administration of 30 mg Ulipristal Acetate

Cmax = maximum concentration
AUC0-t = area under the drug concentration curve from time 0 to time of last determinable concentration
AUC0-∞ = area under the drug concentration curve from time 0 to infinity
tmax = time to maximum concentration
t1/2 = elimination half-life
* Median (range)

Effect of food: Administration of ella together with a high-fat breakfast resulted in approximately 40 - 45% lower mean Cmax, a delayed tmax (from a median of 0.75 hours to 3 hours) and 20 - 25% higher mean AUC0-∞ of ulipristal acetate and monodemethyl-ulipristal acetate compared with administration in the fasting state. These differences are not expected to impair the efficacy or safety of ella to a clinically significant extent; therefore, ella can be taken with or without food.

Distribution

Ulipristal acetate is highly bound (> 94%) to plasma proteins, including high density lipoprotein, alpha-l-acid glycoprotein, and albumin.

Metabolism

Ulipristal acetate is metabolized to mono-demethylated and di-demethylated metabolites. In vitro data indicate that this is predominantly mediated by CYP3A4. The mono-demethylated metabolite is pharmacologically active.

Excretion

The terminal half-life of ulipristal acetate in plasma following a single 30 mg dose is estimated to 32.4 ± 6.3 hours. 

Drug interactions

CYP3A4 inducers: When a single 30 mg dose of ulipristal acetate was administered following administration of the strong CYP3A4 inducer, rifampin 600 mg once daily for 9 days, Cmax and AUC of ulipristal acetate decreased by 90% and 93% respectively. The Cmax and AUC of monodemethyl-ulipristal acetate decreased by 84% and 90% respectively [see Drug Interactions (7.1)].

CYP3A4 inhibitors: When a single 10 mg dose of ulipristal acetate was administered following administration of the strong CYP3A4 inhibitor, ketoconazole 400 mg once daily for 7 days, Cmax and AUC of ulipristal acetate increased by 2- and 5.9- fold, respectively. While the AUC of monodemethyl-ulipristal acetate increased by 2.4-fold, Cmax of monodemethyl-ulipristal acetate decreased by 47%. There was no in vivo drug-drug interaction study between ulipristal acetate 30 mg and CYP3A4 inhibitors [see Drug Interactions (7.1)].

In vitro studies demonstrated that ella does not induce or inhibit the activity of cytochrome P450 enzymes.

P-glycoprotein (P-gp) transporter: In vitro data indicate that ulipristal may be an inhibitor of P-gp at clinically relevant concentrations. When a single 60 mg dose of fexofenadine, a substrate of P-gp glycoprotein, was administered 1.5 hours after the administration of a single 10 mg dose of ulipristal acetate, there was no increase in Cmax or AUC of fexofenadine.

Breast Cancer Resistance Protein (BCRP) transporter: In vitro data indicate that ulipristal acetate may be an inhibitor of BCRP at the intestinal level.

The effects of ella on P-gp and BCRP transporters are unlikely to have any clinical consequences when considering ella's single dose treatment regimen, although there was no in vivo drug interaction study between ulipristal acetate 30 mg (ella) and substrates of P-pg and BCRP transporters.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity:

Carcinogenicity potential was evaluated in rats and mice. 

Sprague Dawley rats were exposed to ulipristal acetate daily for 99-100 weeks at doses of 1, 3, or 10 mg/kg/day, representing exposures up to 31 times higher than exposures at the maximum recommended human dose (MRHD).  There were no drug-related neoplasms in male rats.  In female rats, potential treatment-related neoplastic findings were limited to adrenal cortical adenomas in the intermediate dose group (3 mg/kg/day). Despite the increase, this incidence of adrenal cortical adenomas in females may not be relevant to clinical use.

Tg.rasH2 transgenic mice were exposed to ulipristal acetate for 26 weeks at doses of 5, 45, or 130 mg/kg/day, representing exposures 100 times higher than exposures at the MRHD.  There was no drug-related increase in neoplasm incidence in male or female mice.

Genotoxicity: Ulipristal acetate was not genotoxic in the Ames assay, in vitro mammalian assays utilizing mouse lymphoma cells and human peripheral blood lymphocytes , and in an in vivo micronucleus assay in mice.

Impairment of Fertility:  Single oral doses of ulipristal acetate prevented ovulation in 50% of rats at 2 times the human exposure based on body surface area (mg/m2).  Single doses of ulipristal acetate given on post-coital days 4 or 5 prevented pregnancy in 80-100% of  rats and in 50% of  rabbits when given on post-coital days 5 or 6 at drug exposures 4 and 12 times the human exposure based on body surface area.  Lower doses administered for 4 days to rats and rabbits were also effective at preventing ovulation and pregnancy.

14.1 Open-Label Study

This study was a multicenter open-label trial conducted at 40 family planning clinics in the United States. Healthy women with a mean age of 24 years who requested emergency contraception 48 to 120 hours after unprotected intercourse received a dose of 30 mg ulipristal acetate (ella). The median BMI for the study subjects was 25.3 and ranged from 16.1 to 61.3 kg/m2.

Twenty-seven pregnancies occurred in 1,242 women aged 18 to 35 years evaluated for efficacy. The number of pregnancies expected without emergency contraception was calculated based on the timing of intercourse with regard to each woman's menstrual cycle. ella statistically significantly reduced the pregnancy rate, from an expected rate of 5.5% to an observed rate of 2.2%, when taken 48 to 120 hours after unprotected intercourse.

14.2 Single-Blind Comparative Study

This study was a multicenter, single-blind, randomized comparison of the efficacy and safety of 30 mg ulipristal acetate (ella) to levonorgestrel (another form of emergency contraception). Subjects were enrolled at 35 sites in the U.S., the United Kingdom and Ireland, with the majority (66%) having been enrolled in the U.S. Healthy women with a mean age of 25 years who requested emergency contraception within 120 hours of unprotected intercourse were enrolled and randomly allocated to receive ella or levonorgestrel 1.5 mg. The median BMI for the study subjects was 25.3 and ranged from 14.9 to 70.0 kg/m2. 

In the ella group, 16 pregnancies occurred in 844 women aged 16 to 35 years when emergency contraception was taken 0 to 72 hours after unprotected intercourse. The number of pregnancies expected without emergency contraception was calculated based on the timing of intercourse with regard to each woman's menstrual cycle; ella statistically significantly reduced the pregnancy rate, from an expected 5.6% to an observed 1.9%, when taken within 72 hours after unprotected intercourse. There were no pregnancies observed in the women who were administered ella more than 72 hours after unprotected intercourse (10% of women who received ella).

14.3 Pooled Analysis

Data from the two studies were pooled to provide a total efficacy population of women treated with ulipristal acetate up to 120 hours after UPI. Time Trend analysis for the five 24-hour intervals from 0 to 120 hours between unprotected intercourse and treatment was conducted. There were no significant differences in the observed pregnancy rates across the five time intervals.

Subgroup analysis of the pooled data by BMI showed that for women with BMI > 30 kg/m2 (16% of all subjects), the observed pregnancy rate was 3.1% (95% CI: 1.7, 5.7), which was not significantly reduced compared to the expected pregnancy rate of 4.5% in the absence of emergency contraception taken within 120 hours after unprotected intercourse. In the comparative study, a similar effect was seen for the comparator emergency contraception drug, levonorgestrel 1.5 mg. For levonorgestrel, when used by women with BMI > 30 kg/m2, the observed pregnancy rate was 7.4% (95% CI: 3.9, 13.4), compared to the expected pregnancy rate of 4.4% in the absence of emergency contraception taken within 72 hours after unprotected intercourse.