• (1S, 4R ) -4 - [ 2-amino- 6-( cyclopropylamino ) - 9H -purin- 9-yl ]-2- cyclopentene- 1-methanol
  • (1S, 4R ) -4 - [ 2-amino- 6 - ( cyclopropylamino ) -9H -purin- 9-yl ] cyclopent-2 -en- 1-methanol
  • C14H18N6O ( abacavir )
  • ( C14H18N6O ) 2 · H2SO4 ( 2 abacavir · H2SO4)


Antiviral, nucleoside reverse transcriptase inhibitors

Competitive inhibition of reverse transcriptase

  • 286.33 g · mol -1 ( abacavir )
  • 670.74 g · mol -1 (2 abacavir · H2SO4)

165 ° C ( abacavir )

Template: Infobox chemical / molecular formula search available

Abacavir ( Manufacturer GlaxoSmithKline) is a drug used to treat infected with HIV-1 patients as part of a combination antiretroviral therapy. It belongs to the group of the nucleoside reverse transcriptase inhibitors ( NRTIs).

A special feature is that the therapy is tied with abacavir in a previous genetic test. In this test the presence of the gene marker HLA-B * 5701 is checked. In patients with this genetic marker, there is sometimes life -threatening hypersensitivity reactions.



Abacavir is first converted to the triphosphate. In addition, the base portion is metabolized. As a biologically active metabolite arises carbovir triphosphate. This inhibits the reverse transcriptase. It acts synergistically with nucleosides partially and HIV protease inhibitors in vitro.


Bioavailability is > 70%. The elimination half-life is calculated with about 1.5 hours. To the active triphosphate, intracellular half-life is provided with 3 to 4 hours. To be taken in two divided doses daily to 300 mg. Absorption is independent of meals. With regular use, maximum levels of 3.0 ± 0.9 mg / l are given as AUC was 6.0 ± 1.7 mg / l × h calculated. The concentration in the liquor corresponds to about 1/3 of the plasma concentrations. Abacavir is predominantly ( approximately 85 %) metabolised in the urine excreted. The drug is not metabolized by the cytochrome P450 system. There is no corresponding interaction potential.

Side effects

Main side effect is a hypersensitivity reaction (about 5 %). Symptoms: fever, rash, fatigue, and gastrointestinal symptoms. The pain usually occurs usually between the first and fourth week of treatment. After discontinuation of the medication, the symptoms within one to two days are declining. Abacavir may then not be administered again. A severe life-threatening hypersensitivity reaction with hypotension occurred heaped upon within one to two hours. Lactic acidosis and hepatomegaly were rarely observed.

For the occurrence of hypersensitivity reaction, a genetic predisposition is: In patients with the allele HLA -B * 5701, the hypersensitivity reaction occurs in up to 80 % of cases. Therefore, a genetic test for the presence of the corresponding gene is displayed prior to initiating therapy with abacavir.

It seems that in patients with high cardiovascular risk is an increased risk of heart attack, especially in a newly started abacavir therapy, there is.

Abacavir is metabolized by the enzyme alcohol dehydrogenase. Plasma concentrations may be increased when alcohol is consumed at the same time. Interactions with zidovudine or lamivudine are low. Interactions with the cytochrome P450 system are unlikely.


About the mechanisms of resistance are well known details. Changes in amino acids 65, 74, 115 and 184 of the reverse transcriptase associated with a reduction in sensitivity. Also similar nucleosides such as zalcitabine and didanosine are less effective against these strains usually. To counteract the development of resistance of the combination is absolutely necessary in the context of HAART.


Abacavir is chiral and contains the 1 - and 4-position of the cyclopen two stereogenic centers. Thus, there are four stereoisomers: the (1S, 4S )-form, the (1R, 4R )-form, the (1R, 4S)- form and the (1S, 4R)- form. As a drug, the (1S, 4R )-form of abacavir is used exclusively.

Pharmaceutical information

Is used medicinally, the water soluble abacavir sulfate ( abacavir 2 · H2SO4). It is orally applicable.

Trade names

Ziagen (D, A, CH)

Trizivir (D, A, CH), Trizivir (D, A, CH)