Safety, Tolerability and Therapeutic Efficacy of Topical ZEP-3 Ointment (1.0%) for the Treatment of Cold Sores

The primary endpoint of this study are:

• "Time to healing" - Clinician-assessed duration in days of herpes labialis episode.
• Patient-assessed duration and intensity of pain by Visual Analog Scale (VAS).
• Safety and tolerability following five consecutive treatment days with five times daily topical administration.

The secondary endpoints of this study are:

• Proportion of subjects with non - ulcerative herpes lesion.
• Time for herpes labialis recurrences

Subject safety will be assessed following treatment by ZEP-3 ointment 1.0% or acyclovir cream 5% treatment, using measurements of the following variables:

• Physical examination,
• Vital Signs (HR, BP, Body temperature),
• Adverse events recording and
• Concomitant medications

Inclusion criteria

Prior to enrollment in this study, candidates must meet ALL of the following inclusion criteria:

• Patients suffering from recurrent Herpes labialis with history of at least 3 cold sores recurrences during the previous 12 months.
• Participants, either male or female are between 18 and 75 years of age.
• Patients arrive at the clinic with any symptom of an acute Herpes labialis episode.

Or, patients arrive at the clinic within 48 hours of treatment initiation for a recurrent Herpes labialis episode.

• Patients with previous Herpes labialis episode must be healed for at least 14 days before baseline visit
• Patients with no history of reaction to topical products.
• Female subjects of childbearing potential must have a negative pregnancy test at screening and agree to use a proper contraceptive method during the study.
• Participant understands the nature of the procedure and is willing and able to comply with all requirement of the protocol.
• Patient is willing and able to provide written informed consent prior to any study procedure.

Exclusion criteria

• Subject has abnormal skin conditions or significant facial hair at or near the investigational area
• Subject has any body piercing in or around the area ordinarily affected by cold sores.
• Subjects with a history of cardiac abnormalities.
• Subject has a recent history of renal dysfunction or serious hepatic disease
• Subject has an active malignancy or immunodeficient disease
• Subject who is unwilling to stop using topical medical, OTC, cosmetics or facial skin care products in or around the oral area during the study period.
• Subject requires chronic use of immunomodifying drugs or topical steroids on or near the face.
• Subject requires chronic use of anti-viral medication.
• Subject requires chronic use of analgesics, pain medication or non-steroidal anti inflammatory agents (NSAIDs).
• History of allergic or adverse response to acyclovir, or any related anti-viral drug.
• Subject has had an infection with HSV-1 isolates know to be resistant to acyclovir, valacyclovir, famciclovir, or ganciclovir.
• Subject has had a herpes vaccine.
• Females during pregnancy, lactation or breastfeeding.
• Subject has a history of alcoholism or drug abuse within the preceding 12 months.
• Subject is currently enrolled in another clinical trial involving the use of a drug and/or a device.
• Any history which, in the Investigator's judgment, makes the subject ineligible or places the subject at undue risk.
• Subjects with immune deficiency conditions including acquired immune deficiency.