Ayfer Bahar

and 3 more

Aim: Chirality of drugs might be associated with safety issues through pharmacokinetic or pharmacodynamic variations, interactions, or direct toxicological responses. This study aimed to examine chiral status of the drugs withdrawn from the market. Methods: We searched the literature regarding withdrawn drugs between 1950-2020 due to safety-related issues and identified 395 drugs. We examined their chirality and assigned into one of three categories: achiral compound, chiral mixture, and pure enantiomer. We compared their distribution at ATC-1 level, duration on the market, and adverse drug reactions leading to their withdrawal. Results: We identified that 52.4% (n=207) of withdrawn drugs were achiral, whereas 27.6% (n=109) were chiral mixtures and 20.0% (n=79) were pure enantiomers. The mean duration on the market was 24.6±27.5 years. The groups did not differ in terms of mean duration on the market. Chiral mixtures were significantly more withdrawn than were achirals in cardiovascular system drugs (17.4% vs. 7.7%, p=0.01). In musculoskeletal system drugs, pure enantiomers were significantly less withdrawn (2.5%) compared to achirals (12.6%, p=0.01) and chiral mixtures (11.9%, p=0.03). Hepatotoxicity was significantly less common in pure enantiomers (5.4%) compared to chiral mixtures (12.7%, p=0.04) and achirals (17.0%, p<0.01). Cardiovascular toxicity was significantly more common in chiral mixtures (14.5%) compared to that in achiral drugs (7.5%, p=0.02). Conclusion: Our study showed slightly higher representation of chiral mixtures among withdrawn drugs over pure enantiomers. The assessment of withdrawal reasons further indicates higher tendency of chiral mixtures towards hepatotoxicity and cardiovascular toxicity.