The purpose of the current phase I study was to establish bioequivalence, safety, and tolerance of single 300 IU subcutaneous dose of follitropin alfa biosimilar (Primapur) in comparison to that of reference follitropin alfa preparation (Gonal-F) in healthy young female volunteers.

A Phase I, prospective, randomized, open-label, crossover, 2-period, two treatment, clinical study in healthy female volunteers.

Objectives of the study:

1. To evaluate the frequency and severity of adverse events (AE) following a single 300 IU subcutaneous injection of Primapur (IVFarma, LLC, Russia) and Gonal-F (Merck Serono S.p.A., Italy) to healthy volunteers.
2. To determine the AUC0-t value of Primapur following a single 300 IU subcutaneous injection to healthy volunteers.
3. To determine the T½ value of Primapur following a single 300 IU subcutaneous injection to healthy volunteers.
4. To determine the Сmax value of Primapur following a single 300 IU subcutaneous injection to healthy volunteers.
5. To determine the Tmax value of Primapur following a single 300 IU subcutaneous injection to healthy volunteers.
6. To compare the obtained pharmacokinetic characteristics of Primapur and Gonal-F.

Inclusion Criteria:

1. Healthy female volunteers aged 18 to 40 years.
2. Body mass index (BMI) of 18.5 to 30.0 kg/m2.
3. Subjects who have used oral contraceptives for at least 2 menstrual cycles before study entry.
4. Regular menstruation cycle (24 to 35 days) before initiation of oral contraception.
5. Presence of both ovaries.
6. Subjects who are negative for drugs of abuse and alcohol tests at screening.
7. Subjects who are healthy as validated by pre study medical history, physical examination.
8. Subjects with acceptable clinical laboratory test results.
9. A signed informed consent form that confirms in writing the volunteer's consent to participate in this clinical study and the volunteer's willingness to comply with all physician recommendations and protocol limitations for the time of participation in the clinical study.
10. Ability to comply with the requirements of the protocol.
11. Participants in the study, as well as their sexual partners, are knowledgeable and willing to voluntarily, starting from the week before being included in the study and up to 4 weeks after the last dose of the study drug, and in addition to the contraceptive used, use at least 1 barrier contraceptive method or spermicide.

Exclusion Criteria:

1. Hypersensitivity to follitropin alpha, combined oral contraceptive (ethinylestradiol and drospirenone) or excipients.
2. Allergy, angioedema (hereditary or idiopathic) in history.
3. Previous history of ovarian hyperstimulation syndrome (OHSS).
4. Inability to establish a venous catheter for blood sampling.
5. Presence of polycystic ovaries (PCO) and ovarian cysts.
6. Neoplasia and a history of malignant disease.
7. Deep vein thrombosis, pulmonary embolism.
8. Subjects with impaired thyroid function.
9. Regular usage or administration of any drugs, including non-prescription drugs, vitamins, homeopathic remedies and dietary supplements, less than 2 weeks before the study (with the exception of contraceptive pills).
10. Admission less than 2 months before the start of the study of drugs that have a pronounced effect on hemodynamics, liver function, and medication contained follicle stimulating hormone (FSH), luteinizing hormone (LH), chorionic gonadotropin (hCG), clomiphene, gonadotropin-releasing hormone (GnRH) analogues.
11. Cardiovascular, bronchopulmonary, nervous, endocrine systems, gastrointestinal tract, liver, kidney, hematopoietic, immune systems, mental diseases.
12. Acute infectious diseases less than 4 weeks before the start of the study.
13. Systolic pressure less than 100 mm or above 130 mm Hg; diastolic pressure less than 70 mm or above 90 mm Hg; heart rate less than 60 or more than 80 beats/min.
14. Blood donation less than 3 months before the start of the study.
15. Participation in clinical studies of drugs less than 3 months before the start of the present study.
16. More than 5 alcohol units per week (1 unit is equal to 50 ml of a strong alcoholic drink, 200 ml of dry wine or 500 ml of beer) or anamnestic information about alcoholism, drug addiction, drug abuse.
17. Smoking more than 5 cigarettes/day.
18. Narcomania, alcoholism.
19. Presence of pregnancy.
20. Lactating.
21. Any reason that, in the opinion of the investigator, could interfere with safety of the subject or interfere with the objectives of the study.
22. Subjects with a lactose intolerance, lactase deficiency or glucose-galactose malabsorption.

Women aged 18 to 40 years; body mass index (BMI) of 18.5 to 30 kg/m2

From the study day 1 to day 56.

An adverse event was defined as any adverse event that began following the first dose of follitropin alfa administration till the end of follow-up period. Adverse events were reported from the 1st period (9 days), wash out period (10 days), 2nd period (9 days) and follow-up period (28 days).