This trial is a double-blind, multicenter, placebo-controlled clinical trial. Participants are randomized to topical 15% SP-303 gel and oral acyclovir or to matching topical placebo gel and oral acyclovir. At presentation, patients are stratified by total lesion area within each treatment group. SP-303 or matching placebo is topically applied three times a day until all lesions are reepithelialized or for 14 days, whichever occurs earlier. Acyclovir is administered by mouth each day, three times a day, until all lesions are reepithelialized or for 14 days, whichever occurs earlier. Patients are evaluated for lesion healing and adverse events 3 times per week during the treatment period. The primary efficacy endpoint will be complete lesion healing and the primary analysis will be time to complete healing.

Inclusion Criteria

Patients must have:

• AIDS, according to the CDC criteria.
• Documented recurrent (at least 1 prior episode) perineal (genital, perianal and neighboring areas) mucocutaneous herpes simplex virus (HSV) types 1 or 2 infection in the active phase.
• Duration of current episode of recurrent HSV lesions of 3 days or less.
• Ability to read and write, must be intellectually competent, and able to understand the purposes and risks of the study.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms and conditions are excluded:

• Active internal anal or rectal herpes.
• Inability to comply with protocol.
• Impaired renal function.

Patients with the following prior conditions are excluded:

• Prior episode of recurrent genital herpes infection with documented clinical failure of acyclovir as a treatment regimen.
• Uncompensated hepatic, cardiac, or renal failure within 1 month of the study.
• History of hypersensitivity to acyclovir.

• Previous enrollment in this study.

  1. Treatment with another medication (topical, oral, or intravenous) with known anti-HSV activity within the past 5 days.

• Systemic immunomodulatory therapy within 30 days prior to study.
• Previous treatment with SP-303.

Required:

Unchanged antiretroviral therapy for the 2 weeks prior to study.