This is a single dose, randomized, single blind, parallel group study to evaluate the testosterone suppressive effect in healthy male volunteers of a novel leuprolide acetate 3.75mg depot vs market reference leuprolide acetate 3.75mg depot. The safety, tolerability and the pharmacokinetic properties of the investigational drug and the control drug will also be assessed.

Inclusion Criteria:

1. Males of 18-40 years old (inclusive). The age difference of subjects within and between groups should be less than 10 years, at the time of screening.
2. Body weight of at least 50kg. BMI to be 19-24 kg/m2 (inclusive).
3. Able to comprehend the full nature and purpose of the study, including potential risks and side effects; able to cooperate with investigators and to comply with the requirements of the study
4. Signed informed consent form prior to any screening procedures

Exclusion Criteria:

1. Clinically significant and relevant history of cardiovascular, hepatic, renal, hematologic, endocrine, respiratory, neurological diseases or acute/chronic diseases of the digestive tract.
2. History of hypersensitivity towards leuprolide, synthetic LHRH or LHRH derivatives or any excipients of the study formulation.
3. Abnormal and clinically significant 12-lead ECG
4. Abnormal and clinically significant laboratory assessments
5. Blood donation or blood loss greater than or equal to 400mL within 3 months prior to screening
6. Participation of clinical trials within 3 months prior to screening
7. Use of any drugs within 2 weeks prior to screening
8. History of drug abuse within 1 year prior to screening
9. History of alcohol abuse within 1 years prior to screening
10. History of tobacco smoking (more than 5 cigarette per day) within 1 year prior to screening
11. Abnormal testosterone level at screening (not in the range of 168-781ng/dL)
12. Dermatitis or skin anomalies that might affect the administration area and the surroundings
13. Subject or his partner not willing to adopt appropriate contraceptive measures
14. Subjects have a history of depressive illness or sexual dysfunction;
15. Subjects that the investigator deems unsuitable to be enrolled
16. Subject not willing to cooperate with the investigators.