In the United States (US), only the Food and Drug Administration (FDA)-approved drug products serve as comparator products in bioequivalence (BE) studies. Using foreign comparator drug products raises concerns about comparability to FDA-approved Reference Listed Drugs (RLD), particularly regarding quality standards and therapeutic equivalence. There is potential for differences in BE that may result from even slight differences between the foreign comparator and the US-approved RLD. Such discrepancies can compromise safety, efficacy, and product performance, undermining market access by disrupting manufacturing and supply chain operations for generic drug products. This paper examined biowaiver considerations, product-specific guidances, labeling requirements, and manufacturing guidelines from nine regulatory agencies: FDA, ANVISA (Brazil), COFEPRIS (Mexico), EMA (European Union), Health Canada (Canada), MHLW/PMDA (Japan), SAHPRA (South Africa), Swissmedic (Switzerland), and TGA (Australia). The analysis focused on foreign comparator drug product considerations for parenteral, otic, and ophthalmic solutions, identifying regulatory similarities and differences across jurisdictions. Generally, biowaivers for in vivo BE studies are considered acceptable for these drug products across jurisdictions. However, criteria for qualitative (Q1) and quantitative (Q2) sameness between generic and RLD formulations vary among regulatory agencies. Labeling requirements also differ, though Q1 information is typically mandated for inclusion. Regarding quality-related regulations—including specifications, container and closure systems, stability, storage conditions, and CMC post-approval changes—most regulatory authorities align with international guidelines, particularly ICH quality guidance documents. This alignment suggests potential harmonization opportunities while acknowledging jurisdictional variations in specific requirements for the utilization of foreign comparator products to establish BE for generic drug products.