Evatanepag

A novel coronavirus [severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), or 2019 novel coronavirus] has been identified as the pathogen of coronavirus disease 2019. The main protease (Mpro, also called 3‐chymotrypsin‐like protease) of SARS‐CoV‐2 is a potential target for treatment of COVID‐19. A Mpro homodimer structure suitable for docking simulations was prepared using a crystal structure (PDB ID: 6Y2G; resolution 2.20 Å). Structural refinement was performed in the presence of peptidomimetic α‐ketoamide inhibitors, which were previously disconnected from each Cys145 of the Mpro homodimer, and energy calculations were performed. Structure‐based virtual screenings were performed using the ChEMBL database. Through a total of 1 485 144 screenings, 64 potential drugs (11 approved, 14 clinical, and 39 preclinical drugs) were predicted to show high binding affinity with Mpro. Additional docking simulations for predicted compounds with high binding affinity with Mpro suggested that 28 bioactive compounds may have potential as effective anti‐SARS‐CoV‐2 drug candidates. The procedure used in this study is a possible strategy for discovering anti‐SARS‐CoV‐2 drugs from drug libraries that may significantly shorten the clinical development period with regard to drug repositioning.

Prostaglandin (PG) E analogs are used clinically to ripen the cervix and induce labor. However, selective receptor agonists may have potential to improve induction response rates or manage unwanted uterine hypercontractility in conditions such as dysmenorrhea and preterm labor. To characterize their therapeutic value, PGE₂ analogs were used to investigate the functional E-type prostanoid (EP) receptor population in isolated human uterus. Responsiveness in mouse tissues was also examined to validate its use as a preclinical model. Uterine samples were obtained from mice at dioestrus (n = 12), term gestation (n = 14), and labor (n = 12) and from the lower uterus of women undergoing hysterectomy (n = 12) or Caesarean section (n = 18). Vehicle and agonist effects were assessed using superfusion and immersion techniques. PGE₂ evoked predominant excitatory responses in mouse and relaxation in human tissues. Selective EP₄ agonists inhibited tissue activity in both nonpregnant species, while the EP₂ mimetic CP533536 also attenuated uterine contractions throughout gestation. The uterotonic effects of the EP_3/1 agonist sulprostone were more pronounced than the EP₁ agonist ONO-D1-004, corresponding to abundant EP₃ receptor expression in all samples. The contractile phenotype in mouse compared with human uteri may relate to regional differences as well as high expression of EP₃ receptor transcripts. Similarities in nonpregnant and gestational tissues across species suggest that EP₃ may represent a valuable translational drug target for preventing uterine hypercontractility by employing a selective antagonist. SIGNIFICANCE STATEMENT: This research validates the use of nonpregnant mice for preclinical drug discovery of uterine EP receptor targets. To determine the utility of novel drugs and delivery systems at term pregnancy and labor, pharmacological agents interacting with EP₃ receptors have clear translational value.