Inclusion Criteria:

          1. Female or male subjects, at least 27 years old.

          2. Confirmed diagnosis of intra-anal HSIL at least 3 months prior to screening and
             confirmed by histopathology (with p16 positive staining)

          3. Intra-anal HSIL are visible and evaluable by HRA at the time of screening, and no
             lesion(s) is suspicious for invasive cancer.

          4. For HIV-positive subjects, CD4 count must be at least 200/mm3 with undetectable (<50
             copies/mL) viral load within the 3 months prior to enrollment. Subjects must be on a
             stable regimen of antiretroviral drugs for the 3 months prior to enrollment.

        Exclusion Criteria:

          1. Women who are pregnant, plan to become pregnant in the next 3 months, or lactating
             females.

          2. Received topical treatment or ablative procedures for aHSIL in the 6 months prior to
             enrolment.

          3. History of cancer, including anal cancer (with the exception of basal cell or squamous
             cell carcinoma of the skin), or currently undergoing treatment for any skin cancer.

          4. History of genital herpes with > 3 outbreaks per year.

          5. Plan to have excision or ablation of the lesion(s) within 3 months of enrolment.