Innovation challenge: You can't do it alone
- 1970s: A new class of molecules, nitroimidazole derivatives, were synthesized. Amongst several nitroimidazoles, some were found to have good anti mycobacterial properties. Ciba Geigy developed CGI017341 as the lead compound. But later it was found to be mutagenic (i.e. likely to change the patients’ DNA) and research stopped.
- 1995: One failure on a compound doesn’t mean failure in the entire field and research on nitroimidazole derivatives continued. In 1995 the PathoGenesis Corporation identified a promising series of nitroimidazopyrans for the treatment of TB and related mycobacterial diseases. PA-824 was discovered during a screening of substituted nitroimidazopyrans as potential anti-tubercular agents . PathoGenesis started preclinical development of PA-824.
- In 2000, Chiron acquired PathoGenesis, including PA-824 and all research results into this agent.
- In 2002, Chiron licensed the development of PA-824 (and its analogs) to the Global Alliance for TB Drug Development, with a commitment to make the TB technology available royalty-free in endemic countries.
- 2019: The TB Alliance carried forward the development of PA-824, leading to the announcement of the approval of Pretomanid on 14 August 2019 as part of the BPal regimen . Research on analogs of PA-824 continues.
- bedaquiline from Janssen and
- linezolid, available from multiple manufacturers, including Mylan.
 Another promising compound was OPC-67683, which in the meantime was developed by Otsuka into Delamanid, approved by the EMA in 2014.