Chroma Medicine Presents Data Demonstrating Near-Complete, Durable In Vivo Silencing with Targeted Epigenetic Editors at 2023 ASGCT Annual Meeting

Company unveils two programs and data demonstrating robust and durable single-dose silencing of PCSK9 and hepatitis B virus (HBV) with epigenetic editors

Data validate the potential of harnessing an innate mechanism for gene regulation to enable highly efficient, specific, and durable gene modulation across a broad range of diseases

BOSTON, May 18, 2023 /PRNewswire/ -- Chroma Medicine, Inc., (Chroma) a genomic medicine company pioneering single-dose epigenetic editing therapeutics, today announced in vivo data that demonstrate 99% silencing of two distinct targets and compelling proof-of-concept for its epigenetic editing platform. The data presented at the American Society of Gene & Cell Therapy (ASGCT) 26^th Annual Meeting showcase the rapid advancement of the company's programs and platform.

The work describes the development of Chroma's epigenetic editor targeting PCSK9, a well-characterized genetic target for addressing hyperlipidemia. The company's epigenetic editor showed highly effective, durable, and specific silencing of PCSK9 in a transgenic mouse. Ninety-nine percent silencing of PCSK9 was observed following a single dose of Chroma's epigenetic editor through a minimum of five months of observation with no detectable off-target changes in gene expression or methylation.

In addition, Chroma's presentation highlighted the broad utility and modularity of its epigenetic editors. Data shared demonstrate that exchanging the PCSK9 targeting guide RNA with one directed towards the HBV genome induced robust and durable reduction of hepatitis B surface antigen (HBsAg) below the lower limit of quantification following a single administration in a transgenic HBV mouse model.

"These data illustrate the inherent power of epigenetic editing. The robust efficiency, durability, and specificity of silencing observed at two distinct targets underscore the advantages of harnessing an endogenous mechanism for gene regulation," said Vic Myer, Ph.D., Chroma's President and CSO. "In combination with our multiplex editing data—and data from the lab of our scientific co-founder Dr. Angelo Lombardo also presented at ASGCT—the results underscore the transformative potential of epigenetic editing as the modality of choice for gene regulation."

The company expects to present additional data at upcoming scientific meetings, signaling advancement of its broad portfolio of highly differentiated epigenetic editing therapeutics for patients living with serious diseases.

Details for Chroma's oral presentations at ASGCT are as follows:

Title: Development of a Human PCSK9-Targeted Epigenetic Editor with Durable, Near-Complete In Vivo Silencing Efficiency
Presenter: Aron Jaffe, Ph.D., Senior Vice President, Head of Research
Date and Time: Thursday, May 18^th, 2:30p PT
Session: Gene Targeting and Gene Correction: Liver

Title: Multiplexed Editing Without Chromosomal Rearrangements Using Epigenetic Editors
Presenter: Sahar Abubucker, Senior Director, Data Science
Date and Time: Friday, May 19^th, 4:45p PT 
Session: Genome & Epigenome Editing Technologies

The presentations will be archived on the Chroma website following the meeting.

About Chroma Medicine

Chroma Medicine is a biotechnology company pioneering a new class of genomic medicines that harness epigenetics, nature's innate mechanism for gene regulation, to deliver precise, programmable, single-dose therapeutics while preserving genomic integrity. The company was founded by the world's foremost experts in genomic research and is led by a veteran team of industry leaders and scientists with deep experience in genomic medicine, drug discovery, and development. For more information, please visit chromamedicine.com or follow the company on LinkedIn and Twitter.

SOURCE Chroma Medicine