History
Oseltamivir was discovered by scientists at Gilead Sciences using shikimic acid as a starting point for synthesis; shikimic acid was originally available only as an extract of Chinese star anise; but by 2006, 30% of the supply was manufactured recombinantly in E. coli.[70][71] Gilead exclusively licensed their relevant patents to Roche in 1996.[72] The drug has not been patent-protected in Thailand, the Philippines, Indonesia, and several other countries.[72]
In 1999, the FDA approved oseltamivir phosphate for the treatment of influenza in adults[73] based on two double-blind, randomized, placebo-controlled clinical trials.[74] In June 2002, the European Medicines Agency (EMA) approved oseltamivir phosphate for prophylaxis and treatment of influenza. In 2003, a pooled analysis of ten randomised clinical trials concluded that oseltamivir reduced the risk of lower respiratory tract infections resulting in antibiotic use and hospital admissions in adults.[75]
Oseltamivir (as Tamiflu) was widely used during the H5N1 avian influenza epidemic in Southeast Asia in 2005. In response to the epidemic, various governments – including those of the United Kingdom, Canada, Israel, United States, and Australia – stockpiled quantities of oseltamivir in preparation for a possible pandemic[76] and there were worldwide shortages of the drug, driven by the high demand for stockpiling.[70] In November 2005, US President George W. Bush requested that Congress fund US$1 billion for the production and stockpile of oseltamivir, after Congress had already approved $1.8 billion for military use of the drug. Defense Secretary Donald Rumsfeld, who was a past chairman of Gilead Sciences, recused himself from all government decisions regarding the drug.[77]
In 2006, a Cochrane Review (since withdrawn) raised controversy by concluding that oseltamivir should not be used during routine seasonal influenza because of its low effectiveness.[78]
In December 2008, the Indian drug company Cipla won a case in India's court system allowing it to manufacture a cheaper generic version of Tamiflu, called Antiflu. In May 2009, Cipla won approval from the World Health Organization (WHO) certifying that its drug Antiflu was as effective as Tamiflu, and Antiflu is included in the WHO list of prequalified medicinal products.[79]
In 2009, a new A/H1N1 influenza virus was discovered to be spreading in North America. In June 2009, the WHO declared the A/H1N1 influenza a pandemic.[80] The National Institute for Health and Care Excellence (NICE), the US Centers for Disease Control and Prevention (CDC), the WHO, and the European Centre for Disease Prevention and Control (ECDC) maintained their recommendation to use oseltamivir.[6][81]
From 2010 to 2012, Cochrane requested Roche's full clinical study reports of their trials, which they did not provide.[82] In 2011, a freedom of information request to the European Medicines Agency (EMA) provided Cochrane with reports from 16 Roche oseltamivir trials. In 2012, the Cochrane team published an interim review based on those reports. In 2013, Roche released 74 full clinical study reports of oseltamivir trials after GSK released the data on zanamivir studies.[83] In 2014, Cochrane published an updated review based solely on full clinical study reports and regulatory documents.[37][82] In 2016, Roche's oseltamivir patents began to expire.[72]
