Can a generic manufacturer use a different ingredient/excipient while still submitting drug as a generic?

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The generic needs to have the same API (Active Pharmaceutical Ingredient) composition (qualitative and quantitative) as the one of the brand leader.
There is no obligation to have the same composition in excipients, even though some generic companies prefer to stick to the same excipients as long as they have the same dosage form.
ex.: immediate release film-coated tablet,  there is no problem to use Lycoat or ReadiLycoat instead of HPMC or PVA  based coating system as long as it has the same functionality.

Other questions - General

Does Roquette as a manufacturer has to perform identification tests?

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How does sorbitol ingestion influence blood glycemia?

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What is the available information on the effect and dosage of polyols on newborn babies during the first months?

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What is the viscosity of a non-crystallizing liquid sorbitol such as NEOSORB 70/70 B?

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