Non nucleoside reverse transcriptase inhibitors

NNRTI

Nevirapine, delavirdine and efavirenzbelong to the group of non-nucleoside reverse transcriptase inhibitors (NNRTIs). They bind directly and non-competitively to the reverse transcriptase of HIV and block the polymerase activity by deregulating the catalytic part of the enzyme. In contrast to NRTIs, NNRTIs do not

require activation within the cell. NNRTIs are non-competitive inhibitors of mainly HIV-1 reverse transcriptase. NNRTIs were introduced between 1996-1998. On their own, they are not so potent, but in combination with a NRTI they are extremely effective.

NNRTIs are metabolized by CYP450 3A enzymes in the liver and thus can interact with many drugs such as, astemazole, midazolam, cyclosporine, rifampicin and erythromycin.

Nevirapine can cause serious hepatotoxicity. Therefore, liver functions need to be monitored during therapy.

1

Because nevirapine induces cytochrome P450 enzymes, interactions with other drugs like macrolides, protease inhibitors, and rifampicin can occur.

2

Nevirapine is used to treat early HIV infection with minor immune deficiency.