- Human immunodeficiency virus (HIV)-positive patients without a prior acquired immune deficiency syndrome (AIDS)-defining illness and a CD4 count 400/millimeter^3 and either do not require anti-HIV therapy or are taking anti-HIV therapy that would not interfere with GDC-0449 (e.g. not taking zidovudine, protease inhibitors or non-nucleoside reverse transcriptase inhibitors) are eligible