Atazanavir is a Proteases Inhibitor (PI)  that was approved in 2003.  It is usually prescribed along with ritonavir or cobicistat.  Generally well tolerated with few side effects.  Take once or twice a day with food.  It is considered safe for use during pregnancy. 

Inform your doctor if you have Hepatitis-C.  It should not be used with sildenafil (VIAGRA) and should not be taken directly with grapefruit juice.