FlagshipPioneering launched SerifBiosciences this morning with $50M behind Modified DNA, their term for non-viral, programmable, redosable DNA medicines that don't integrate into the genome.

The approach that stands out is how they're getting the DNA into the nucleus. Serif is co-delivering mRNA alongside it to act as a chaperone, rather than relying on a better LNP alone. Nuclear entry has been the wall DNA therapeutics keep hitting, so using a second nucleic acid to solve it is a genuinely different bet.

They've also been developing this for five years inside Flagship Labs and are presenting NHP tolerability data and preclinical efficacy at an upcoming meeting.

The open questions are the familiar ones like durability at therapeutic doses, and whether this translates beyond the liver.