Nexium just missed the top-15 with 2010 worldwide sales of $4.97B. Your link shows Nexium as #3 in 2009 (behind Lipitor and Plavix); dropping from #3 to #16 is indeed a big fall.
Nexium may be the most medically useless mega-blockbuster in history, so I’m not sorry to see it fall out of the top-15 list.