Polymerase Selection And Its Impact On IVT Outcomes For Self-Amplifying RNA

When manufacturing self-amplifying RNA, the polymerase you select for in vitro transcription is not a trivial decision. On a 9.5 kb linearized DNA template encoding saRNA with a firefly luciferase reporter, head-to-head data show measurable differences in three critical quality attributes: double-stranded RNA contamination, capping efficiency, and total RNA yield.

dsRNA is a known immunogenic byproduct of IVT reactions, and elevated levels can undermine therapeutic performance. Capping efficiency, assessed by LC-MS, directly affects translational competency. Yield, measured by UV absorbance, determines process economics at scale. The comparison featured here was conducted by an independent contract organization using standardized buffer conditions; 9 mmol NTPs, 4 mmol Cap AU analog, 37°C, two-hour incubation applied equally to both enzymes, reducing confounding variables and giving the data credibility.

If your current IVT process is producing inconsistent integrity profiles on fragment analysis or higher-than-acceptable dsRNA per microgram of mRNA, polymerase engineering may be where the answer lies. Watch the full video presentation to see the quantitative comparison across all three performance metrics and understand what the data mean for your saRNA process development strategy.