Method for optimizing post-translational modifications on recombinant proteins

A method for producing a biosimilar protein by optimizing a growth medium for living cells that produce a recombinant protein having a target set of post-translational modifications, said method comprising:

• a) measuring post-translational modifications on a reference product protein,
• b) setting target post-translational modification ranges for the recombinant protein based on the measured post-translational modifications of the reference product protein,
• c) providing a living host cell that expresses the recombinant protein,
• d) placing said host cells in growth media containing a first set of post-translational modulators having a first set of concentrations,
• e) identifying the post-translational modifications on the recombinant protein and determining the differences between the identified post-translational modifications and the target post-translational modification, ranges based on the reference product protein as determined in step b), and
• if the target post-translational modification of the recombinant protein are not within the target post-translational modification ranges determined in b), then:
• f) developing a second set of post-translational modulators wherein the second set of post-translational modulators may include a different set of modulators from the first set, different concentrations of modulators from the first set, or a combination of different modulators and different concentrations of modulators,
• g) producing the recombinant protein from the cells engineered to express the recombinant protein in a growth media in the presence of the modified second set of post-translational modulators,
• h) isolating the recombinant protein from growth media and comparing its post-translational modifications to the target set of post-translational modifications,
• i) repeating steps e), f), g), and h) until a set of post-translational modulators is identified that can be used to produce a recombinant protein having the target set of post-translational modulations.