First-in-human study evaluating safety, pharmacokinetics, and pharmacodynamics of lorundrostat, a novel and highly selective aldosterone synthase inhibitor.

Dysregulation of the mineralocorticoid hormone aldosterone is an increasingly prevalent cause of hypertension. Aldosterone synthase (CYP11B2) shares 93% homology to 11ß-hydroxylase (CYP11B1), which produces cortisol. Lorundrostat, a highly selective inhibitor of CYP11B2, is a potential safe and effective treatment for aldosterone-dependent, uncontrolled hypertension, including treatment-resistant hypertension. Lorundrostat showed highly selective inhibition of CYP11B2 in vitro, with 374-fold selectivity for CYP11B2 vs. CYP11B1. A first-in-human study of single ascending doses ranging from 5 to 800 mg and multiple ascending doses ranging from 40 to 360 mg once daily was conducted in healthy participants. After single- and multiple-dose administration, lorundrostat plasma levels peaked 1-3 h after administration with a t1/2 of 10-12 h. Plasma aldosterone decreased up to 40% with single 100-mg to 200-mg doses and up to 70% with single 400 to 800-mg doses. Plasma aldosterone returned to baseline within 16 h after single 100-mg doses and multiple once-daily 120-mg doses. Lorundrostat demonstrated a favorable safety profile in healthy participants. Dose- and exposure-dependent inhibition of renal tubular sodium reabsorption was observed across a clinically relevant dose range with no suppression of basal or cosyntropin-stimulated cortisol production and only a modest increase in mean serum potassium.

Sucrose Solution Ingestion Exacerbates Dinitrofluorobenzene-Induced Allergic Contact Dermatitis in Rats.

Allergic dermatitis is a skin disease with growing prevalence worldwide that has been associated with diets high in fats and sugars. Regular consumption of sucrose-containing beverages may increase the risk for several health problems, including allergic diseases and particularly asthma, but the association between sucrose consumption and allergic dermatitis is understudied. We investigated the effects of sucrose solution intake on allergic contact dermatitis in rats and found early exacerbation of 2,4-dinitrofluorobenzene (DNFB)-induced disease symptoms and altered composition of the gut microbiota after 14 d of intake. The levels of short-chain fatty acids-produced by fermentation by the intestinal microbiota-were not affected in the cecal contents and feces but decreased in the blood; this effect was especially notable for acetate. To restore blood acetate concentrations, triacetin was mixed with a 10% sucrose solution and fed to the rat model. This strategy prevented the early exacerbation of DNFB-induced symptoms. The decreased absorption of short-chain fatty acids from the intestinal lumen was not linked to the decreased expression of short-chain fatty acid transporters in the small intestine; instead, the mechanism involves a reduction in the sodium concentration in the intestinal lumen due to increased expression of sodium-glucose transporter 1 (SGLT1).