Testing of HLA-B*57:01 is recommended prior to the initiation of this anti-retroviral agent
Ref. KDT. Page.  808
Abacavir

It is a potent ARV drug that acts after intracellular conversion to carbovir triphosphate.
Resistance to ABC develops slowly
Its oral bioavailability is 80% and it is mainly eliminated by metabolism.
The plasma t1⁄2 is 1–1.5 hour, but intracellular t1⁄2 of active metabolite is >12 hours.
Hypersensitivity reactions such as rashes, fever, flu-like symptoms are the major problems.
To avoid anaphylactic reactions in response to the drug HLA-B*57:01  testing is mandatory pre-treatment. 
Avoidance of alcohol is advised.
Atazanavir
Nelfinavir
Raltegravir
Abacavir