Nontherapeutic equivalence of a generic product of imipenem-cilastatin is caused more by chemical instability of the active pharmaceutical ingredient (imipenem) than by its substandard amount of cilastatin.

ABSTRACT: BACKGROUND:We demonstrated therapeutic nonequivalence of "bioequivalent" generics for meropenem, but there is no data with generics of other carbapenems. METHODS:One generic product of imipenem-cilastatin was compared with the innovator in terms of in vitro susceptibility testing, pharmaceutical equivalence, pharmacokinetic (PK) and pharmacodynamic (PD) equivalence in the neutropenic mouse thigh, lung and brain infection models. Both pharmaceutical forms were then subjected to analytical chemistry assays (LC/MS). RESULTS AND CONCLUSION:The generic product had 30% lower concentration of cilastatin compared with the innovator of imipenem-cilastatin. Regarding the active pharmaceutical ingredient (imipenem), we found no differences in MIC, MBC, concentration or potency or AUC, confirming equi

SUBMITTER: Agudelo M 

PROVIDER: S-EPMC6364906 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature