Scribe Therapeutics is adding another $100 million to its coffers six months after unveiling a $20 million series A and a partnership with Biogen to work on gene editing treatments for amyotrophic lateral sclerosis (ALS). The new funds will support the development of the company’s gene editing and delivery technologies and propel a pipeline of treatments for neurodegeneration and other diseases.
That initial round was about laying the groundwork for a company that aims to overcome the obstacles in CRISPR, Scribe CEO Benjamin Oakes, Ph.D., who founded the company alongside Nobel Prize winner Jennifer Doudna, Ph.D., Brett Staahl, Ph.D., and David Savage, Ph.D.
“Our last round was very much ‘just do it,’ building our core … This round is more about building the entire organization,” Oakes said.
Scribe’s work, like that of many gene editing biotechs, is based on CRISPR, a system that evolved in bacteria to fight off pathogens. CRISPR molecules include a guide RNA that recognizes the target DNA sequence and an enzyme, usually Cas9, that cuts it. Scientists including Doudna’s team at the University of California, Berkeley have discovered more enzymes over the years, but relying on enzymes found in nature limits the possibilities of CRISPR.
“We continue to engineer [CRISPR molecules] on the two core axes that are important for editing: efficacy and specificity, with the ability to edit with the lowest dose possible,” Oakes said.
Rather than “shoehorning” enzymes that evolved to work well in bacteria—but not in humans—into treatments for human disease, Scribe is engineering CRISPR molecules from scratch. This will allow the company to address problems seen in traditional CRISPR, such as safety, efficacy and off-target effects, where the treatment edits untargeted parts of the genome, causing harmful side effects.
It is developing treatments for delivery via adeno-associated viruses, or AAVs, the best understood way to get CRISPR treatments into the body. But it’s also working on alternative, nonviral delivery methods, Oakes said.
Scribe’s pipeline is still in the discovery stages, so the company isn’t sharing details just yet. It has identified several areas where its tech could be useful, including genetic forms of blindness, neuromuscular diseases and blood disorders as well as neurological diseases.
Its treatments will work in vivo, correcting disease-causing mutations inside the body. However, its technology can be used ex vivo, or outside the body, too.
“We’re not focused on that, but we’re excited to work with the best people in the field to apply our technologies ex vivo where others need it,” Oakes said.
The company’s first technology, known as X-Editing, is based on CRISPR-CasX, which was discovered in Doudna’s lab. Many more technologies are in the works, both on the delivery front and on the molecule front, Oakes said, but the company is keeping those under wraps for now.
Under the Biogen deal, the Big Biotech handed over $15 million upfront to work on treatments for ALS, with the option to add another neurological disease target. Scribe could pick up as much as $400 million in development and commercial milestone payments.