Former bluebird execs hope to fly new startup to 'cutting edge' of gene therapy delivery tech

The untapped potential of gene editing therapies comes down to one major challenge: getting gene editors safely and efficiently into cells. Now, a startup founded by two genetic medicine luminaries and run by former executives from bluebird bio is officially emerging from stealth mode to reveal its solutions to the industry. 

Nvelop, named for the way its tech envelopes its gene editing cargo and carries it to cells, formally announced its existence on April 9 in a press release. Founded in 2022 by David Liu, Ph.D., and Keith Joung, M.D., Ph.D., the company plans to build its own medicines as well as offer its delivery tech to industry partners.  

“One of the biggest challenges for many of the gene editing companies—and even beyond gene editing—is the ability to efficiently in vivo deliver cells at a relevant dose that doesn't challenge safety signals,” Jeff Walsh, former chief strategy officer at bluebird who joined Nvelop as CEO a year ago, told Fierce Biotech Research in an interview. “That's what we think we can deliver, ultimately.”

Walsh is leading Nvelop alongside chief scientific officer and fellow bluebird veteran Melissa Bonner, Ph.D., who served as senior vice president and head of research at bluebird until she joined Nvelop in September 2023. Walsh’s tenure at bluebird saw the company grow from a startup to a well-known player in the gene therapy space, while Bonner’s saw it clinch three FDA approvals—one for Zynteglo, one for Skysona and one for Lyfgenia—in just two years. 

“Bluebird was a really great opportunity to really understand how to get something into the clinic and beyond, and to be leading on the cutting edge of cell and gene therapy was such an amazing, humbling experience,” Bonner said. “I'm just really excited because I think the biggest challenge of the field today is delivery, and I think we're in a really fortunate position of being able to lead on that front edge again.”

Nvelop’s stealth launch in 2022 was fueled by $100 million in seed funding from Atlas Venture, F-Prime Capital, Newpath Partners, 5 AM Ventures and Arch Venture Partners. The startup was based around two separate but complementary gene editor delivery technologies developed by Liu’s lab at the Broad Institute and Joung’s work at Massachusetts General Hospital. Both utilize engineered viruslike particles (eVLPs), which are loaded up with gene editing machinery and sent to specific cells. Ideally, eVLPs overcome the safety issues with virus-based platforms, the specificity problems of lipid nanoparticles and the low carrying capacity of both.

Nvelop has spent its two years in stealth mode validating the platforms and their potential path to the clinic. Liu’s platform was already backed up by mouse data published in Cell prior to the company’s formation. In January 2024, it got another data set under its belt, this time in Nature Biotechnology. The Cell article describes experiments where eVLPs were used to carry gene editors to the liver, central nervous system and eyes, while the Nature Biotechnology paper shows they can be used in a gene therapy that partially restores vision in mice with genetic blindness. 

While animal data on Joung’s technology haven’t yet been published—they were less mature than Liu’s when the company was formed, Bonner said—Nvelop plans to share some at scientific meetings later in 2024. Joung’s platform also comes with a library of human envelope proteins that can be placed on the membrane of the eVLP and direct it to different tissues. These are likely interchangeable between both platforms and could potentially make them safer, Bonner said. 

“We believe having both of them in vivo validated with this high degree of modularity and the potential for interchanging components gives us a lot of optionality, which we’re really excited about,” she said. 

Crucially, Nvelop also has confirmed that it will be able to scale up manufacturing of its platforms without losing any of their editing efficiency—a major challenge for cell and gene therapy companies, as others have discovered. With those data in hand, the company’s leaders are ready to create their first product and test it out. 

“Aside from continuing to prosecute the platform and its properties, the next big challenge for us is getting a particle—however it’s designed, leveraging whatever platform components—and driving it toward relevant animal models,” Walsh said. “Now that we are confident in our ability to scale both platforms, we have the opportunity to [obtain] that kind of data.” 

Until Nvelop has data on relevant disease models, it’s too early to say what therapeutic areas it will target first, though the team “has a good idea of where we want to point the engine,” Walsh added. Meanwhile, even as the startup works on its own product strategy, partnerships with other companies are in the works. Without disclosing any specifics, Walsh noted that Liu’s published data on his platform’s editing efficiency have piqued “significant interest” from would-be partners. So has its broad applicability to different cell types, its ability to carry larger cargoes and, of course, its scalability. 

“We continue to have conversations on partnerships to be able to enable others,” Walsh said. “So it’s a dual product-partnership strategy.”