N-Acetylgalactosamine (GalNAc), is an amino sugar derivative of galactose. GalNAc conjugation represents an efficient way of increasing siRNA target organ accumulation and of facilitating their cellular uptake.
Our team has extensive experience in the synthesis of various types of GalNAc molecules, including Mono-GalNAc, Tri-GalNAc, Tetra-GalNAc, GalNAc amidite, GalNAc PFP ester, GalNAc N3, GalNAc-PEG conjugate, etc. We provide GalNAc custom synthesis, process development and GMP manufacturing supporting from discovery phase all the way to commercial launch with batch scales ranging from milligrams to over 50 kilograms.
With our oligo team on the same site in Changzhou China, we provide a streamlined GalNAc-oligo conjugate development and manufacturing service. With various GalNAc building blocks and CPG/PS conjugate resin in stock, we can further accelerate your GalNAc-oligo projects.
WuXi TIDES solution to overcome GalNAc synthesis challenges
There are many synthetic challenges for GalNAc because most of the intermediates are oily or foamy solids. The synthesis involves many columns and prep-HPLC purification steps, resulting scale-up difficulties and low yields. Analytical method for GalNAc synthesis is also challenging due to low UV response, complex impurity profile and poor stability.
Enabled by strong chemistry platform, WuXi TIDES developed convergent routes with telescoping processes without column purification steps. The isolated intermediates are stable solids. We apply the precipitation process and/or spray drying process to reduce the need for column and prep-HPLC steps. Our analytical team identify many GalNAc-related impurities to support method development and release testing.