EFFICACY AND SAFETY OF THE ESTETROL/DROSPIRENONE ORAL CONTRACEPTIVE IN US STUDY PARTICIPANTS WITH AND WITHOUT OBESITY

Objectives

We aimed to compare contraceptive efficacy and safety of estetrol 15 mg/drospirenone 3 mg in US study participants with and without obesity.

Methods

We analyzed US population data from a phase 3 trial of estetrol/drospirenone use for up to 13 cycles. The study enrolled 1,864 healthy US and Canadian participants 16-50 years old with body mass index (BMI) 18-35 kg/m². We evaluated efficacy (Pearl Index, pregnancies/100-person-years) in participants 16-35 years and safety (adverse events [AEs]) in all participants, with obesity defined as BMI≥30 kg/m².

Results

We included 1,712 (91.8%) US participants; 1,531(89.4%) were 16-35 years. BMIs for 418 (24.4%) participants with obesity were 32.6±1.7 kg/m² overall and 32.6±1.8 kg/m² for 365 participants aged 16-35. For participants without obesity, BMIs were 23.9±3.2 kg/m2 and 23.8±3.3 kg/m², respectively. Pearl indices for participants with and without obesity were 3.04 (95% CI, 1.116.61) and 2.86 (95% CI, 1.754.42), respectively (p>0.05). AEs were reported by 418 (56.0%) and 670 (51.8%) of participants with and without obesity (p=0.13). The most common AE that differed between groups was weight gain (5.3% vs 2.7%, respectively, p=0.02). Two serious AEs (1 per group) were considered study treatment related. Discontinuation for an AE occurred in 40(9.6%) and 116 (9.0%), respectively (p=0.7).

Conclusions

Contraceptive efficacy did not differ for US estetrol/drospirenone users with and without obesity. Although participants with obesity more frequently report weight gain, overall AE discontinuation rates did not differ. These results demonstrate a favorable efficacy and safety profile of estetrol/drospirenone users with obesity.