No developmental toxicity observed with dolutegravir in rat whole embryo culture.

Background: An in vitro rat whole embryo culture study investigated whether direct exposure to dolutegravir (Tivicay ) during the critical period for neural tube development would result in abnormal development.

Methods: Dolutegravir (DTG), and HIV integrase inhibitor, was administered at 0 (vehicle), 5.3 μg/mL and 9.

Absence of developmental and reproductive toxicity in animals exposed to dolutegravir.

The success of new antiretroviral medicines for HIV resulted in a change to guidelines of standard therapy where continuation of antiretroviral therapy is recommended to maintain the low viral load during pregnancy, thereby preventing transmission of the virus to the fetus. As a result, pregnancy related exposure to HIV medicines has increased. Understanding the safety of these medicines during pregnancy is of paramount importance to ensure health of mothers and their offspring; well-designed animal studies that evaluate the reproductive life cycle play a key role in this effort.

Clinical Extrapolation of the Effects of Dolutegravir and Other HIV Integrase Inhibitors on Folate Transport Pathways.

Preliminary analysis of ongoing birth surveillance study identified evidence of potential increased risk for neural tube defects (NTDs) in newborns associated with exposure to dolutegravir at the time of conception. Folate deficiency is a common cause of NTDs. Dolutegravir and other HIV integrase inhibitor drugs were evaluated in vitro for inhibition of folate transport pathways: proton-coupled folate transporter (PCFT), reduced folate carrier (RFC), and folate receptor (FR)-mediated endocytosis.

Species- and dose-specific pancreatic responses and progression in single- and repeat-dose studies with GI181771X: a novel cholecystokinin 1 receptor agonist in mice, rats, and monkeys.

Compound-induced pancreatic injury is a serious liability in preclinical toxicity studies. However, its relevance to humans should be cautiously evaluated because of interspecies variations. To highlight such variations, we evaluated the species- and dose-specific pancreatic responses and progression caused by GI181771X, a novel cholecystokinin 1 receptor agonist investigated by GlaxoSmithKline for the treatment of obesity.

PPAR alpha, more than PPAR delta, mediates the hepatic and skeletal muscle alterations induced by the PPAR agonist GW0742.

Therapeutic use of certain peroxisome proliferator-activated receptor (PPAR) alpha agonists (fibrates) for the treatment of dyslipidemia has infrequently been associated with the untoward side effect of myopathy. With interest in PPAR-delta as a therapeutic target, this study assessed whether a PPAR-delta agonist induced similar hepatic and skeletal muscle alterations as noted with some fibrates. PPAR-alpha null (KO) and corresponding wild-type (WT) mice were administered toxicological dosages of a potent PPAR-delta agonist tool ligand (GW0742; which also has weak PPAR-alpha agonist activity) or a potent PPAR-alpha agonist (WY-14,643) for 10 days.

Gene expression profiling of the PPAR-alpha agonist ciprofibrate in the cynomolgus monkey liver.

Fibrates, such as ciprofibrate, fenofibrate, and clofibrate, are peroxisome proliferator-activated receptor-alpha (PPARalpha) agonists that have been in clinical use for many decades for treatment of dyslipidemia. When mice and rats are given PPARalpha agonists, these drugs cause hepatic peroxisome proliferation, hypertrophy, hyperplasia, and eventually hepatocarcinogenesis. Importantly, primates are relatively refractory to these effects; however, the mechanisms for the species differences are not clearly understood.