Biopsy-proven HSIL (anal intraepithelial neoplasia 2 [AIN2] with a positive p16 stain, AIN 2-3, or AIN3) of the anal canal at either the squamocolumnar junction or distal anus, documented within 60 days prior to enrollment, but not less than 7 days prior to randomizationXx_NEWLINE_xXBiopsy-proven anal HSIL at baseline (anal intraepithelial neoplasia [AIN]2 with a positive cyclin-dependent kinase inhibitor 2A [p16] stain, AIN2-3, or AIN3)Xx_NEWLINE_xX