Impact of mRNA chemistry and manufacturing process on innate immune activation.

Messenger RNA (mRNA) represents an attractive therapeutic modality for potentially a wide range of clinical indications but requires uridine chemistry modification and/or tuning of the production process to prevent activation of cellular innate immune sensors and a concomitant reduction in protein expression. To decipher the relative contributions of these factors on immune activation, here, we compared, in multiple cell and in vivo models, mRNA that encodes human erythropoietin incorporating either canonical uridine or N1-methyl-pseudouridine (1mΨ), synthesized by either a standard process shown to have double-stranded RNA (dsRNA) impurities or a modified process that yields a highly purified mRNA preparation. Our data demonstrate that the lowest stimulation of immune endpoints was with 1mΨ made by the modified process, while mRNA containing canonical uridine was immunostimulatory regardless of process. These findings confirm that uridine modification and the reduction of dsRNA impurities are both necessary and sufficient at controlling the immune-activating profile of therapeutic mRNA.

Design of a series of bicyclic HIV-1 integrase inhibitors. Part 1: selection of the scaffold.

HIV integrase inhibitors based on a novel bicyclic pyrimidinone core is presented. Nine variations of the core scaffold are evaluated leading to optimization of the 6:6 core giving compound 48 with an EC(50) of 3 nM against wild type HIV infected T-cells.