AZT, DD1, HAART are combination of three drugs are used in AIDS acts by

(Nucleoside reverse transcriptase inhibitors) (770-KDT 6th)* Nucleoside reverse transcriptase inhibitors (NRTIs) -Zidovudine (AZT), Didanosine (ddl) Stavudine (d4T) Lamivudine (3TC) abacavir(ABC)Single- stranded viral RNA||Virus directed reverse transcriptase(Inhibited by zidovudine triphosphate)Double - stranded viral DNA* Non nucleoside reverse transcriptase inhibitors (NNRTIs)Nevirapine (NVP) Efavirenz (EFV) Delavirdine* Protease inhibitors - Ritonavir, Indinavir, Nelfinavir, Saquinavir* Fusion inhibitor - Enfuvirtide (binding to HIV envelope glycoprotein (grp 41) and preventing fusion of viral and cellular membranes