MaxCyte , the Rockville, Maryland-based cell-engineering company, has launched two new off-target nomination assays, CHANGE-seq-BE™ and ONE-seq-BE™, built specifically to evaluate safety risk in therapies that use base editors rather than traditional gene-editing nucleases. Both are delivered through the company’s existing SeQure™ service, which now folds these into a broader portfolio of assays gene-editing developers can use to flag where a base editor might be cutting or altering DNA outside its intended target. President and CEO Maher Masoud framed the launch around the distinct safety questions base editors raise: “Base editors are creating new opportunities for therapeutic development, while also requiring safety assessment strategies that reflect their mechanisms of action. The addition of CHANGE-seq-BE and ONE-seq-BE to our SeQure services gives developers access to sensitive, orthogonal off-target assessment capabilities that can help them to better understand and mitigate off-target risk, building stronger data packages for clinical development.”
What These Two Assays Actually Do
CHANGE-seq-BE is a sensitive, unbiased biochemical method for nominating potential off-target sites in adenine and cytosine base editors. ONE-seq-BE goes a step further: MaxCyte describes it as the only nomination assay for base editors that offers full visibility into population-specific genetic variants that could influence where off-target activity occurs. Together, the two assays are meant to be used alongside each other rather than as substitutes, since the SeQure platform is built around comparing results across multiple nomination methods to help developers see where flagged sites overlap and diverge, then prioritize which sites need deeper confirmation testing.
Why This Launch Aligns With FDA Guidance
MaxCyte ties this launch to evolving FDA expectations around off-target editing and genome safety, pointing to a growing emphasis on orthogonal assays, assay sensitivity, and modality-appropriate methods. The company frames CHANGE-seq-BE and ONE-seq-BE as a response to base editors requiring safety assessment strategies suited to their own mechanisms of action, positioning the assays as a way for developers to build stronger data packages for clinical development.
A Rockville Company Expanding an Already Established Platform
These two assays aren’t a new business line for MaxCyte — they’re additions to SeQure, a service the company offers alongside its core Flow Electroporation® cell-engineering technology. MaxCyte, headquartered in Rockville, Maryland, has spent more than 25 years building out its cell-engineering platform, and this launch extends that work into the base-editing subset of the gene-editing field.
