Chlormadinone, Ethinyl Estradiol

Pharmacological properties

continuous use of the drug Belar for 21 days inhibits the secretion of FSH and LG by the pituitary gland and, as a result, suppresses ovulation. endometrial proliferation and its secretory transformation occurs. the consistency of cervical mucus also changes. this complicates the passage of sperm through the cervical canal and leads to a violation of their mobility.

The minimum dose of chlormadinone acetate (HMA), providing a complete suppression of ovulation, is 1.7 mg. The dose required for endometrial transformation is 25 mg per cycle.

HMA is a progestogen with antiandrogenic properties. The mechanism of its action is based on the ability to replace androgens at specific receptors and may have a beneficial effect (for example, control of endogenous androgen and a decrease in the severity of acne or hirsutism).

The combined result of data from 6 large non-intervention studies was analyzed to evaluate the effectiveness of contraception, cycle parameters, dysmenorrhea symptoms and skin diseases when using tablets containing 0.03 mg of ethinyl estradiol (EE) and 2 mg of HMA for young and adult women with standard or prolonged cycles. Data on the use of the drug by 60 508 women (325 937.5 cycles) and their results are shown in the table:

At first, the prevalence of seborrhea and acne in 73.7% of young and 73.5% of adult women was the same for age subgroups, with the exception of adults aged ≥35 years, where it was slightly lower (66%). In each subgroup, there was a significant decrease in the severity of skin problems during the observation period. On the final visit, only 45.9% of young and 47.3% of adult women had seborrhea and acne.

The combination of EE and HMA led to a very low pregnancy rate, giving practically a Pearl index of 0.34 (95% confidence interval (CI) 0.27–0.42):

• in young patients: the practical Pearl index 0.36 (95% CI 0.22-0.55), the theoretical Pearl index 0.09 (95% CI 0.03-0.2), including 75 761.75 cycles;
• in adult patients: practical Pearl index 0.33 (95% CI 0.25–0.42), theoretical Pearl index 0.07 (95% CI 0.04–0.12), including 246 082.50 cycles.

The effect of the drug containing 0.03 mg EE and 2 mg HMA for moderate papular pustular acne was evaluated in a placebo-controlled study (6 treatment cycles, 251 women) compared with a drug containing 0.03 mg EE in combination with 0 15 mg of levonorgestrel (12 treatment cycles, 200 women). The main indicator of effectiveness was the proportion of patients for whom a 50% reduction in the number of papules and / or pustules in half of the face was detected between the first examination and the 6th or 12th treatment cycle.

The drug containing EE 0.03 mg and HMA 2 mg achieved a statistically significant high response rate in the treatment of acne compared with placebo (64.1 versus 43.7%). For seborrhea, the general resolution for the 6th cycle was 41.5% of patients using 0.03 mg EE tablets and 2 mg HMA for 23.9% of patients receiving placebo. Compared to EE / levonorgestrel, 0.03 mg EMA tablets and 2 mg HMA achieved a statistically significant high response rate with acne versus reference drug (59.4 versus 45.9%, ITT analysis). Regarding seborrhea, a complete cure on the 12th cycle occurred in 80% of patients using 0.03 mg EE and 2 mg HMA, compared with 76.2% of patients taking EE / levonorgestrel.

Clinical efficacy

In clinical trials in which