- Chroma Medicine, a Boston-based biotechnology startup focused on drugs that can alter the epigenome, revealed Wednesday that it has raised a $135 million Series B round.
- The company, which emerged from stealth in 2021 with $125 million, was co-founded by a team of gene editing pioneers: Jonathan Weissman, David Liu, Keith Joung, Luke Gilbert, Luigi Naldini and Angelo Lombardo.
- Chroma specializes in a field of biomedical research known as epigenetic editing. While the company has not disclosed a pipeline or therapeutic area of focus, it plans to release preclinical data from two of its research programs later this year.
Epigenetic editing has piqued the interest of scientists and biotech investors in recent years for its promise to offer another approach to change gene expression.
Researchers see epigenetic editing as less disruptive to the underlying genome than forms of gene editing like CRISPR that change genetic sequences. The original form of CRISPR editing, for example, cuts through DNA's double-stranded helix, which can pose risks should that cutting be led astray.
With epigenetic editing, DNA isn’t directly altered, meaning a treatment’s effects could be reversible and more subtly dial gene expression up or down. The approach’s potential has already led to the creation of a few startups in recent years, among them Chroma and Epic Bio. Chroma, which built its platform from research published in 2021 by Weissman and is the most richly funded of the group, aims to use the technology to target complex diseases.
Catherine Stehman-Breen, Chroma’s CEO, said the Series B financing will help the company gather more data but did not share when it might advance a drug candidate into clinical trials.
“We are choosing indications in tissues where we know we can deliver our drug, with biology that we understand where there are clear biomarkers,” said Stehman-Breen, a former Sarepta Therapeutics executive who previously worked at Amgen and Regeneron.
Chroma is developing ways to combine the activation and silencing of genes. The company is focused on "multiplexing," which involves hitting several genes simultaneously and precisely in a way a gene cutter or base editor cannot.
"What we're not going to do is fix a broken gene," said Vic Myer, the company’s chief scientific officer and a former executive at Editas Medicine and Novartis.
"If you need to knock a large piece of DNA into the genome in a specific location, we're not going to do that either,” Myer said. “We think where you should apply this technology is regulating genes that are in the genome."
Chroma’s latest financing round was led by GV, with participation from 15 other investors, including Arch Venture Partners, Alexandria Venture Investments and Atlas Venture.
The funding is notable given the tough financing environment for young drug companies. Already, more than 20 biotechs have restructured this year, and private financings remain harder to raise than they were a few years ago.
A January report from analysts at Silicon Valley Bank found a “steady decline” in Series B activity in recent months, compared to Series A investments in 2020 and 2021. Increasingly, venture firms appear to want strong clinical results, or at least a clear line of sight to obtaining human data, before funding a Series B round, SVB said.
Chroma was able to secure its round anyway, buoyed by continued investor interest in gene editing companies. Now “we can begin to take additional risk and be able to address a broader range of indications,” Stehman-Breen said.
Correction: This article has been corrected to note Chroma was founded by six scientists, not three.