Recombinant proteins expressed in mammalian cells are properly folded, glycosylated and generally yield a functionally active protein [36].
However, the production cost of biopharmaceuticals using mammalian
expression system is very high due to expensive culture media. However, when we look at the number of
approved biopharmaceuticals by United States and/or the
European Union for 2013 recorded above average as compared
to past five years. The mean rate of approval is 13 as
shown in the Figure 2 [5-13]. Remarkably, the number is
same for both the years 2009 and 2013.