Abacavir

Abstract

▴ Abacavir is a nucleoside analogue reverse transcriptase inhibitor that inhibits clinical isolates of HIV in vitro with a potency similar to that of zidovudine. ▴ Resistance to abacavir develops relatively slowly. Cross-resistance between abacavir and didanosine, zalcitabine or lamivudine, but not zidovudine or stavudine, has been reported in vitro. ▴ Abacavir has good oral bioavailability, as demonstrated in animals, and penetrates the CNS. ▴ Treatment with abacavir, alone or in combination with other anti-HIV agents (zidovudine, lamivudine, nevirapine, amprenavir and/or other protease inhibitors), decreased viral load and increased CD4+ cell count in patients with HIV infection. Effectiveness was maintained for at least 48 weeks. ▴ In early phase I/II trials, headache, gastrointestinal disturbances, rash, malaise, fatigue and/or asthenia were the most common adverse events reported with abacavir alone or in combination with other anti-HIV agents. Hypersensitivity reactions lead to discontinuation of therapy in 2 to 3% of patients.