Abacavir (as sulfate)
Abacavir (as sulfate) is used for: For the treatment of HIV-1 infection, in combination with other antiretroviral agents. Oral HIV infection
Combined with other antiretrovirals: 300 mg bid or 600 mg once daily.
Child: ≥3 mth 14 to <20 kg: 150 mg bid or 300 mg once daily; ≥20 kg to <25 kg: 150 mg in the morning and 300 mg in the evening or 450 mg once daily; ≥25 kg: Same as adult dose.
May be taken with or without food.
- HLA-B*57:01 allele positive patients - Moderate to severe hepatic impairment. - Lactation. - Hypersensitivity to abacavir
Hepatic Impairment: Mild (Child-Pugh score 5-6): 200 mg bid. Contraindicated in Moderate to severe Hepatic Impairment.
Side effects of Abacavir (as sulfate) : Fever, cough, rash, lethargy, malaise, dyspnoea, headache, GI disturbances, myalgia, particularly nausea, vomiting, diarrhoea and abdominal pain; pancreatitis and elevated liver enzyme values, osteonecrosis, immune reconstitution syndrome, MI, lipodystrophy syndrome. Rarely: Stevens-Johnson syndrome, erythema multiforme, toxic epidermal necrolysis. Potentially Fatal: Serious and fatal hypersensitivity reactions w/ multiple organ involvement, lactic acidosis and severe hepatomegaly w/ steatosis.
Mechanism of Action
Abacavir is a carbocyclic synthetic nucleoside analogue and an antiviral agent. Intracellularly, abacavir is converted by cellular enzymes to the active metabolite carbovir triphosphate, an analogue of deoxyguanosine-5'-triphosphate (dGTP). Carbovir triphosphate inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA. Viral DNA growth is terminated because the incorporated nucleotide lacks a 3'-OH group, which is needed to form the 5' to 3' phosphodiester linkage essential for DNA chain elongation.