Novel Bacterial Topoisomerase Inhibitor Gepotidacin Demonstrates Absence of Fluoroquinolone-Like Arthropathy in Juvenile Rats.

Fluoroquinolone use in children is limited due to its potential toxicity and negative effects on skeletal development, but the actual effects/risks of fluoroquinolones on bone growth and the mechanisms behind fluoroquinolone-driven arthropathy remain unknown. Gepotidacin is a novel, bactericidal, first-in-class triazaacenaphthylene antibiotic with a unique mechanism of action that is not anticipated to have the same risks to bone growth as those of fluoroquinolones. Gepotidacin is in phase III clinical development for uncomplicated urinary tract infections (ClinicalTrials.

The nonclinical fertility study design for pharmaceuticals.

Assessment of potential developmental and reproductive toxicity of human pharmaceuticals is currently guided by the ICH S5(R2) document, "Detection of Toxicity to Reproduction for Medicinal Products and Toxicity to Male Fertility." Studies that assess a candidate drug's effect on fertility are generally conducted in rats. The evolution of, and ultimate harmonization of, fertility study designs are reviewed, and specific elements of an acceptable design, as well as the recommendations for presentation of data, are described in detail.

Embryo-fetal developmental toxicity study design for pharmaceuticals.

Assessment of potential developmental and reproductive toxicity of human pharmaceuticals is currently guided by the International Conference on Harmonization (ICH) S5(R2) document (available at http://www.ich.org).

Developmental toxicity of artesunate in the rat: comparison to other artemisinins, comparison of embryotoxicity and kinetics by oral and intravenous routes, and relationship to maternal reticulocyte count.

Background: The antimalarial, artesunate, is teratogenic and embryolethal in rats, with peak sensitivity on Days 10 and 11 postcoitum (pc).

Methods: We compared the developmental toxicity of structurally related artemisinins, dihdyroartemisinin (DHA), artemether (ARTM), and arteether (ARTE) to that of artesunate after oral administration to rats on Day 10 pc. In separate studies, embryolethality was characterized after single intravenous (IV) administration of artesunate on Day 11 pc, and toxicokinetic parameters following oral and IV administration were compared.