The Colorado AIDS Clinical Trials Unit (ACTU) conducts a wide range of clinical trials offering experimental treatments with antiretrovirals and immune therapy for adults at all stages of HIV disease. Studies of therapies for opportunistic infections are also available. The Colorado ACTU is one of the 30 ACTU’s that comprise the AIDS Clinical Trials Group (ACTG). ACTG trials are funded by the National Institute of Allergy and Infectious Diseases (NAIDS). Study medications and related tests are in most cases free of charge. Additional HIV/AIDS studies sponsored by drug companies are available. The Colorado ACTU has its main study site at the University of Colorado at Denver and Health Sciences Center (UCDHSC).