Evaluating MED2005 & Nitrostat Bioavailability

Inclusion Criteria: 1. Healthy male subjects between 18 and 50 years of age, inclusive (at screening). 2. A BMI of 18.5-30 kg/m2 (inclusive). 3. No clinical significant abnormal serum biochemistry, haematology and urine examination values as defined by the Investigator. 4. A negative urinary drugs of abuse screen. A positive alcohol test may be repeated on admission at the discretion of the Investigator. 5. Negative HIV and Hepatitis B and C results. 6. No clinically significant abnormalities in 12-lead ECG as defined by the Investigator. 7. No clinically significant deviation outside the normal ranges for blood pressure and heart rate measurements as defined by the Investigator (please refer to appendix 1 for normal ranges). 8. Subjects (unless anatomically sterile (documented evidence) or where abstaining from sexual intercourse is in line with the preferred and usual lifestyle of the subject) and sexual partners must use 2 effective contraception methods during the trial and for 3 months after the last dose, for example: * Oral contraceptive + condom. * Intra-uterine device (IUD) + condom. * Diaphragm with spermicide + condom. 9. Subjects must be available to complete all periods of the study and the follow-up visit. 10. Subjects must satisfy the PI / designee about their fitness to participate in the study. 11. Subjects must be able to read and understand the informed consent form and must provide written informed consent to participate in the study. Exclusion Criteria: 1. A clinically significant history of gastrointestinal disorder likely to influence IMP absorption (Part 1 only). 2. Use of prescription or non-prescription drugs, including vitamins, herbal and dietary supplements within 28 days (or 5 half-lives (whichever is longer) prior to the first dose of IMP, unless in the opinion of the Investigator and Sponsor's Responsible Physician the medication will not interfere with the study procedures or compose subject safety. 3. Evidence of renal, hepatic, central nervous system, respiratory, cardiovascular or metabolic dysfunction. 4. A clinically significant history of drug or alcohol abuse within 2 years before the first dose of IMP. 5. A clinically significant history of previous allergy/sensitivity to GTN, other nitrates and/or any of the excipients in either the test of reference products. 6. Recent history of using PDE5 inhibitors or alkyl nitrates (e.g. poppers). 7. A history of frequent tension headaches or vascular headaches or migraine. 8. A history of increased intra-cranial pressure or spinal cord injury. 9. A history of severe psychological disorders. 10. A presence of scarring/piercings/tattoos at the site of MED2005 administration (penis) (or any other features that the Investigator considers may influence IMP absorption). 11. Subjects (if uncircumcised) who are not able to retract foreskin of penis easily without any discomfort. 12. Any obvious sensitivity/local tolerability issues at the site of medication application. 13. Inability to communicate well with the investigator (i.e. language problems, poor mental development or impaired cerebral function). 14. Participation in a New Chemical Entity or marketed drug clinical study within the previous 3 months or, five half-lives of study drug, whichever is the longer period. (NB. the three month washout period between trials is defined as the period of time elapsed between the last dose of the previous study and the first dose of the next study). 15. Subjects who smoke (or ex-smokers) who have smoked or used nicotine-containing products (including snuff, chewing tobacco, cigars, pipes or nicotine replacement products) within four months prior to first dose. 16. Donation or receipt of ≥ 450 mL of blood within 3 months before the first dose of IMP. 17. Donation of sperm from the first dose and for at least 3 months after the last dose of IMP.