Sarepta expands gene therapy toolkit, bets $72.5M to hitch a ride on Codiak's exosome tech
Adding another type of fuel to its gene therapy engine, Sarepta has signed Codiak Biosciences as a partner to explore re-dosing of its signature precision medicines for neuromuscular disorders.

For $72.5 million in upfront cash and near-term license fees plus research funding, Codiak is committing to investigate up to five targets on its exosome engineering platform in the coming two years. Once the projects get through the IND stage, Sarepta can opt to take over.
In the process, Sarepta is also building out its constellation of biotech partners — many around the Cambridge, MA area — to cement its reputation as the leading developer of genetic treatments for diseases like Duchenne muscular dystrophy and limb girdle muscular dystrophy. From startup Dyno Therapeutics to the more established Selecta, it’s stacking up on technologies for the toolbox.
Codiak’s specialty is co-opting exosomes, the body’s natural intercellular communication system, to carry payloads wherever they want it — essentially putting an address on it with molecular techniques to achieve targeted delivery.

They also have a crucial property that adeno-associated viruses, the primary vectors for gene delivery, don’t. Codiak CEO Doug Williams calls it “immune-cloaked.”
“Gene therapy has always been one and done only because it has to be,” Williams tells Endpoints News.
But AAV can get trapped into exosomes — something researchers observed when making AAV in mammalian cells, and Codiak has also seen when purifying exosomes from virus producer cells. And when the AAV rides an exosome into cells, they become shielded from neutralizing antibodies, which had been a critical barrier to re-dosing.
The next steps will be to refine the process for slipping AAV into exosomes, rendering it more efficient. It’s as much a manufacturing problem as it’s an R&D question, but that’s what Codiak’s sizable manufacturing group — employing as many staffers as the R&D unit — was built for.
The collaboration also covers other technologies in Sarepta’s arsenal such as gene editing and RNA, CEO Doug Ingram adds.