- A new startup launched on Wednesday with $125 million in funding and plans to use gene editing tools to make drugs that can alter the epigenome, an approach that could yield a new way to treat inherited diseases.
- Chroma Medicine, a startup seeded by Atlas Venture and Newpath Partners and backed by several other investors, is developing so-called epigenetic editors, which are meant to change the complex circuitry that causes genes to make proteins, but not the underlying DNA itself. Chroma hasn't said which diseases it intends to treat.
- Chroma's emergence adds to a long-running effort by drugmakers to target the epigenome with different types of medicines. Epigenetic editing could represent a new path for genetic medicines, which have increasingly focused on ways to more precisely and safely control gene expression.
Epigenetics has intrigued drug researchers for years.
Hundreds of millions of dollars have been spent on research in the field, which studies the chemicals and proteins that tell the genome which genes to turn on and off. The goal has been to identify the key molecular switches that can cause a gene to make a protein and use that information to treat a disease.
But despite the formation of a number of startup companies and drug development alliances over the years, the field hasn't fully lived up to its potential. The most significant progress has come in blood cancer, for which several chemical-based drugs targeting enzymes that help regulate gene expression — medicines like Zolinza, Vydaza and Tazverik — have been approved. But none make much money, and the field's reach remains limited. It's been difficult to distinguish which genes and switches control what, and how to directly impact them without causing other problems.
Over the past several years, multiple companies have emerged with plans to take epigenetic drugs a step further. Syros Pharmaceutical and Fulcrum Therapeutics are trying to use computing tools and genomic insights to develop better epigenetic medicines. Omega Therapeutics, which went public in July, is focused on key sections of DNA it believes to be critical regulators of gene expression.
Now large companies and startups, including Chroma, are bringing to bear tools that scientific researchers and companies have been using to change DNA. Gene editing has shown promise as a method to treat rare, inherited diseases like sickle cell, beta thalassemia and transthyretin amyloidosis. But the potential for accidental, off-target edits brings real health risks. That's led scientists to work on newer approaches meant to be more precise or make changes that aren't permanent.
Epigenetic editing is among them. The concept has already led to alliances between Sangamo Therapeutics and Novartis and Biogen, and now Chroma. Other startups are in the works as well, according to a report in Endpoints News.
Chroma's work is based on research recently published in the journal Cell by a team led by MIT scientist Jonathan Weissman, who co-founded the company along with gene editing specialists including David Liu and Keith Joung. The idea is to use components of the DNA editing system CRISPR to turn genes on or off, or alter the expression of several at a time, without cutting into or changing genetic material.
By doing so, Chroma claims it can treat a wide range of diseases, including complex conditions that are beyond the reach of existing gene manipulation technologies. Its work is in its earliest stages, however. The company didn't specify which diseases it's targeting, or how far away it is from human trials.
The startup is led by Catherine Stehman-Breen, a former Sarepta Therapeutics executive who previously worked with Amgen and Regeneron.