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`CFAD EXHIBIT 1021
`
`
`
`Chapter I. History of Drug Discovery
`
`33
`
`omeprazole (Prilosec)
`
`esomeprazole (Nexium)
`
`{n 1987, a group led by Gunnel Sunden embarked on a focused program in finding an
`omeprazole backup with better bioavailability. Among all the compounds in their hands, only one
`was better than omeprazole. II was the S-(- }-enamiomer of omeprazole, esomeprazole (Nexium).
`When tested in rats? esomeprazoJe was 4- 5 times more bioavailable than the R·enantiomer.82
`Another lucky break was that they tested esomeprazole directly in man and saw similar effects to
`what they observed with rats. Later on, when the two isomers were tested on dogs, no significant
`difference of efficacy was detected for the two isomers. In this case, rat was a better animal model
`than dog. If they used dogs for their initial in vivo tests, they probably would never have found
`esomeprazole. Esomeprazole (Ne.xium) was approved in Sweden in 2000 and in the U.S. in early
`200l,just when Prilosec's U.S. patent expired in April.
`
`Lansoprazole (Prevacid) is another proton pump inhibitor sold by TAP Pharmaceuticals,
`a j oint venture of Abbott Laboratories and Takeda. Two other PPis are pantoprazole (Protoni41
`and rabeprazole (Aciphex).
`
`:7
`
`H o~"'>
`(JC;;-s ~ O/'-...CF3
`
`N
`
`"
`
`I
`
`CH3
`lansoprazole (Prevacid)
`
`pantoprazole (Protonix)
`
`H o~--<::
`0 O~OCH3
`N
`I
`:?'
`I/
`(XN'r
`S
`
`CH3
`rabeprazole (Aciphex)
`
`9
`
`Antiviral Drugs
`
`The first clinically effective antiviral did not become available in 1962 until 5-iodo-2'-