The goal of this clinical trial is to learn about the safety, tolerability and pharmacokinetics of LIB-01 in healthy male participants. The main questions it aims to answer are:

• How safe and tolerable is LIB-01 when given once or repeatedly at different dose levels.
• What are the pharmacokinetic characteristics of LIB-01

Participants will receive LIB-01 and be followed up for safety and pharmacokinetics by:

• Adverse events
• ECG
• Blood sampling for laboratory parameters and pharmacokinetic analysis

Inclusion Criteria

1. Provision of signed and dated written informed consent prior to any trial specific procedures.
2. Healthy male participant aged 18 to 65 years, inclusive.
3. Body mass index ≥ 18.5 and ≤ 30.0 kg/m2.
4. Medically healthy participant without abnormal clinically significant medical history, physical findings, vital signs, ECG and laboratory values.
5. Participants must be willing to use an acceptable form of contraception and refrain from donating sperm from the administration of IMP until 3 months after the administration of IMP. Any female partner of a non-vasectomised male participant who is of child-bearing potential must use an acceptable contraceptive method from at least 2 weeks prior to the administration of IMP to 4 weeks after the administration of IMP.
6. Understands the trial requirements.
7. MAD participants only: Mild to moderate erectile dysfunction.

Exclusion criteria

1. History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or influence the results or the participant's ability to participate in the trial.
2. Any clinically significant illness, medical/surgical procedure or trauma within 4 weeks of the (first) administration of IMP.
3. Malignancy within the past 5 years, with the exception of in situ removal of basal cell carcinoma.
4. Any planned major surgery within the duration of the trial.
5. History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, or history of hypersensitivity to drugs with a similar chemical structure or class to LIB-01.
6. History of priapism.
7. History of glaucoma.
8. History of Non-Arteritic Anterior Ischemic Optic Neuropathy.
9. History of prostatectomy or prostate surgery.
10. Bleeding deficiencies or ongoing anticoagulant therapy that would put the participant at risk.
11. Cardiac disease, including but not limited to uncontrolled hypertension; unstable angina; myocardial infarction or cerebrovascular accident.
12. Any positive result for serum hepatitis B surface antigen, hepatitis C antibodies and/or human immunodeficiency virus (HIV).
13. Abnormal vital signs.
14. Shortened QT interval corrected according to Fridericia (QTcF), prolonged QTcF (>450 ms), cardiac arrhythmias or any clinically significant ECG abnormalities.
15. Use of oral, injectable, or topical pro-erectile drugs or supplements.
16. Use of nitrates.
17. Ongoing antiandrogen treatment.
18. Regular use of any prescribed or non-prescribed medications, within 2 weeks (Part I:SAD) or 4 weeks (Part II: MAD) prior to the (first) administration of IMP, except occasional intake of paracetamol, as well as nasal decongestants without cortisone, antihistamine or anticholinergics for a maximum of 10 days.
19. Planned treatment or treatment with another investigational drug.
20. Current smokers or users of nicotine products.
21. Positive screening result for drugs of abuse or alcohol.
22. History of alcohol abuse or excessive intake of alcohol.
23. Presence or history of drug abuse.
24. History of, or current use of anabolic steroids.