Biotech startups race to turn genes on and off without rewriting DNA

On August 5, 2025, Epicrispr Biotechnologies dosed the first patient in a first-in-human trial of EPI-321 for facioscapulohumeral muscular dystrophy. The milestone points to a softer, and potentially broader, next phase for gene medicine: turning genes up or down without changing the DNA code itself. That approach could open new paths for conditions ranging from high cholesterol to facioscapulohumeral muscular dystrophy, while offering a case for better safety, more reversibility, and finer control than permanent genome edits.

Why epigenome editing is different

Traditional CRISPR therapies aim to cut or rewrite DNA. Epigenome editing works one layer above that, changing how genes are expressed without altering the underlying genetic sequence. That difference is more than technical hair-splitting: a therapy that can dial activity up or down may be easier to tune, and in some cases easier to stop, than a one-shot edit that permanently changes the genome.

Epigenetic editing has moved from concept toward clinic for disease targets that do not require full DNA surgery. In some disorders, the goal is to quiet a harmful gene, not replace it.

The startups trying to make it real

Companies working in the space include Chroma Medicine, Epic Bio, Tune Therapeutics, Omega Therapeutics, Moonwalk Biosciences and Modalis Therapeutics. Epigenome editing is no longer a purely academic idea. It has become a definable therapeutic lane, with financing, platform development and disease selection now advancing in parallel.

If a company can prove that epigenome editing delivers durable control of gene activity with fewer risks than DNA cutting, it could claim an advantage in areas where traditional gene editing is too blunt or too permanent. The test is whether that precision survives the realities of delivery, durability and specificity in the body.

Epicrispr’s FSHD test case

Epicrispr Biotechnologies launched in July 2022 with a $55 million Series A round, then later raised $68 million to advance epigenetic editing for facioscapulohumeral muscular dystrophy, or FSHD.

ClinicalTrials.gov lists a first-in-human study of EPI-321 in adults with FSHD type 1, and the record was last updated on April 22, 2026. EPI-321 is a one-time epigenetic editing therapy designed to silence DUX4 expression, the gene activity tied to the disease. FDA granted the program Fast Track, Rare Pediatric Disease and Orphan Drug designations.

FSHD is exactly the kind of disorder that makes this field attractive to developers. If the therapeutic goal is to reduce toxic gene activity rather than replace a missing gene entirely, epigenome editing offers a more tailored mechanism. The key question is whether early dosing can translate into meaningful and durable clinical benefit.

Why cholesterol is drawing so much attention

The commercial pull is strongest when the target is common, measurable and tied to major medical spending. Cardiovascular disease fits that profile, which is why the cholesterol space has become an early proving ground for gene-based medicine. In early testing, a first-in-human CRISPR therapy targeting ANGPTL3 reduced LDL cholesterol by nearly 50 percent and triglycerides by about 55 percent, figures highlighted in an American Heart Association news release.

The question for epigenome editing is whether a switch-based approach can deliver similar results with a better safety profile, more reversibility, or a wider therapeutic window. That answer has to come from durable human data.

The global race and the real constraints

The competition is not confined to the United States. Epigenic Therapeutics in Shanghai is pursuing cholesterol-lowering epigenetic editing therapies and a hepatitis B program.

Developers still have to solve delivery, prove durability, and show that switching genes on and off does not create new safety problems in humans.