Vertice Pharma asked the FDA to revise its draft guidance on bioequivalence requirements for sucralfate oral suspension ANDA to accept in vitro studies for bioequivalence to the reference drug.

Vertice also argued the draft guidance’s recommended studies do not ensure a generic’s bioequivalence with the reference listed drug, Carafate, and that the requirement for quantitative sameness of excipients is unnecessary.

The company urged the agency to require four additional in vitro tests — quantitative pepsin inhibition, acid diffusion, taurodeoxycholate diffusion and cytoprotection — to show that minor variations in the amount of excipients between the generic and Carafate would have no significant impact on the generic’s therapeutic effect.