 It has been suggested that the inhibition of reverse transcription by the NNRTIs may be due to effects on the RT Rnase H activity and/or template/primer binding.Some NNRTIs interfere with HIV-1 Gag-Pol polyprotein processing by inhibiting the late stage of HIV-1 replication.It is important to gain profound understanding of the various mechanism of action of the NNRTIs in order to develop next-generation NNRTIs and for understanding the mechanism of drug resistance.