Opportunities for More Tailored Approaches to Genotoxicity Testing and Carcinogenicity Strategy for Oligonucleotide Therapeutics: Outcome of an Industry Survey.

The Oligonucleotide Nonclinical Working Group (WG) of the European Federation of Pharmaceutical Industries and Associations conducted an industry survey to understand current practices and regulatory expectations for genotoxicity and carcinogenicity assessment of oligonucleotide therapeutics (ONTs), along with historical genotoxicity testing results. The survey, involving 29 pharmaceutical and biotechnology companies, revealed a consistent absence of genotoxicity across a diverse range of oligonucleotide classes and chemistries, consistent with previous observations. Despite the lack of genotoxicity, companies continue to follow standard testing guidelines, with only limited divergence.

Disposition of glycolic acid into the embryo following oral administration of ethylene glycol during placentation in the rat and rabbit.

In order to evaluate the role of the placenta in the etiology of ethylene glycol (EG) developmental toxicity, the distribution of EG and its main metabolites, glycolic acid (GA) and oxalic acid (OX), into the conceptus was determined at the beginning and completion of placentation in the rat and rabbit. Two groups (n = 28) of timed-pregnant Wistar rats were administered EG (1000 mg/kg bw/day, oral gavage) from gestation day (GD) 6 to either GD 11 or GD 16; similarly, two groups (n = 28) of timed-pregnant New Zealand White rabbits were administered EG from GD 6 to either GD 10 or GD 19. Four animals from each group were sacrificed at 1, 3, 6, 9, 12, 18, or 24 h after the final administration, and maternal blood, extraembryonic fluid, and embryonic tissue were removed for analysis of EG, GA, and OX.

Regulating human safety: How dose selection in toxicity studies impacts human health hazard assessment and subsequent risk management options.

In the EU, one of the key determinants in the regulation and management of substances to ensure adequate protection of human health is the outcome of toxicity studies. These studies should therefore be performed in a way that the data generated are adequate to fulfil all regulatory requirements. However, in recent years, an increasing number of toxicity studies use dose levels that induce only slight, or even no toxicity, while the top dose lies well below the limit dose of 1000 mg/kg bw/d.