NNRTI pocket). Therefore, this NNRTI-binding pocket will inhibit reverse transcription in a way that is distinct to the NRTIs. Nevirapine is not effective against HIV-2, as the pocket of the HIV-2 reverse transcriptase has a different structure, which confers intrinsic resistance to the NNRTI class. Resistance to nevirapine develops rapidly if viral replication is not completely suppressed. The most common mutations observed after nevirapine treatment are Y181C and K103N, which are also observed with other NNRTIs. As all NNRTIs bind within the same pocket, viral strains which are resistant to nevirapine are usually also resistant to the other NNRTIs, efavirenz and delavirdine. However, second generation NNRTIs like rilpivirine and etravirine are effective in treatment for HIV strains resistant to nevirapine and other first generation drugs in that same class. History Nevirapine was discovered by Karl D. Hargrave and colleagues at Boehringer Ingelheim Pharmaceuticals, Inc., one of the Boehringer Ingelheim group of companies. It is covered by U.S. Patent 5,366,972 and corresponding foreign patents. Nevirapine was the first NNRTI approved by the U.S. Food and Drug Administration (FDA). It was approved June 21, 1996 for adults and September 11, 1998, for children. It was also approved in Europe in 1997. As of 2022, Nevirapine is considered "rarely prescribed and no longer recommended." Society and culture Former U.S. President George W. Bush's PEPFAR funding of $500 million to help combat the African AIDS epidemic included nevirapine, among other medications and programs. Several researchers, however, had criticized the drug's clinical trials for underreporting severe adverse reactions and for sloppy recordkeeping without informing the White House. Senator Charles Grassley, noted for his support of whistleblowers, took statements from an NIH whistleblower named Jonathan Fishbein and demanded the Justice Dept. investigate the NIH's conduct in its push to gain FDA approval of nevirapine. In South Africa, the Treatment Action Campaign successfully sued the government over its failure to make nevirapine widely available. In Minister of Health v Treatment Action Campaign the Constitutional Court of South Africa ordered the government to immediately "remove the restrictions that prevent Nevirapine from being made available for the purpose of reducing the risk of mother-to-child transmission of HIV at public hospitals and clinics that are not research and training sites [and] permit and facilitate the use of Nevirapine for the purpose of reducing the risk of mother-to-child transmission of HIV and to make it available for this purpose at hospitals