- Has received 12 or more weeks of anti-HIV drug therapy, consisting of at least 3 drugs. This combination may include a nucleoside reverse transcriptase inhibitor (NRTI), a nonnucleoside reverse transcriptase inhibitor, or a protease inhibitor, or 3 NRTIs. Combinations of NRTIs may not include abacavir (ABC). Patients may have taken ABC if it was not in combination with 2 other NRTIs. (This reflects a change in the requirement for anti-HIV therapy.)