This study is designed to show bioequivalence between Current and New formulation of Aciclovir cream 5% in keratin layer of the epidermis in Japanese Subjects

Inclusion Criteria:

• Healthy Japanese adult males between 20 and 55 years of age, inclusive.

Healthy subjects are defined as individuals who are free from clinically significant disease as determined by their medical history, physical examination, clinical laboratory examinations, vital sign, 12-lead ECG, immunology tests and urinary drug screen test.

• Bodyweight >50 kg and body mass index (BMI) between 18.5 and 28.0 at screening.
• Subjects must be capable of providing written informed consent, which includes compliance with the requirements and restrictions listed in the consent form.
• Baseline QTc interval <450 msec.
• Non-smoker or ex-smoker having ceased smoking for at least 6 months.
• Clinical laboratory examination (AST, ALT, ALP and GGT) at screening are within the normal range.
• The subject is able to attend all visits and complete the study.

Exclusion Criteria:

• Any clinically relevant abnormality identified on the screening physical examination, vital sign measurement, 12-lead ECG recording and/or clinical laboratory examination that is deemed by the principal investigator and/or medical monitor to make the subject ineligible for inclusion because of a safety concern.
• History of regular alcohol consumption exceeding, on average, 14 drinks/week (1 drink = 5 ounces (150 mL) of wine or 350 mL of beer or 1.5 ounces (45 mL) of 80 proof distilled spirits) within 6 months of screening.
• Positive for urine drug at screening.
• Positive for syphilis, HIV antibody, Hepatitis B surface antigen, Hepatitis C antibody or HTLV-1 antibody at screening.
• Donation of blood in excess of 400mL within 4 months or 200mL within 1 months prior to at screening.
• History of drug abuse, or current conditions of drug abuse or alcoholism.
• Participation in a clinical study or post-marketing study with an investigational or a non-investigational product or device within 4 months of preceding the first application of study medication.
• Participation in another clinical study or post-marketing study in which the subject is or will be exposed to an investigational or a non-investigational product or device.
• History of asthma, anaphylaxis or anaphylactoid reactions, severe allergic responses.
• The subject has an allergy for any drug or idiosyncrasy. This excludes a pollen allergy without current symptoms.
• At the part obtaining keratinized layer, having exanthem, pigment abnormality, the skin symptoms such as wounds and/or an excessive sunburn.
• History of clinically significant itching, erythema and/or rash by any paster.