Pharmaceutical Alternatives: Excipients and Impurities-Related Therapeutic Nonequivalence

Drug products contain active ingredients and various excipients, such as binders, solubilizers, and preservatives.

These products may also contain impurities and contaminants, which can sometimes go undetected due to quality control limitations.

For example, heparin may be contaminated with a structurally similar impurity, such as over-sulfated chondroitin sulfate.

Adverse reactions from such contamination may not be evident in a single-dose bioequivalence study but can emerge with chronic drug use.

So, impurity control prevents unintended safety and efficacy issues in generic drug products.

Apart from impurities, degradation during manufacturing, storage, and drug-excipient interactions can compromise a drug’s safety and efficacy.

Additionally, the absence or improper amounts of critical functional excipients can reduce efficacy, even with a high-quality API.

These concerns, relevant to both original and generic drug products, must be addressed when evaluating therapeutic equivalence.