Can 'Gene Writing' overcome CRISPR’s limitations? A groundbreaking startup incubated by a top-tier venture firm may rewrite the future of genetic diseases | Exclusive Interview

Recently, a company called Tessera Therapeutics (hereinafter referred to as 'Tessera') and its proprietary Gene Writing™ technology (hereinafter 'Gene Writing') have drawn attention from BioShine. Unlike CRISPR—which modifies only a few base pairs or cuts both strands of DNA—Gene Writing enables precise insertion of long DNA sequences into the genome without breaking the double helix, thereby expanding the scope of editable genes. Tessera was founded in 2018 by Flagship Pioneering, a renowned life sciences venture capital firm. In July this year, the company emerged from 'stealth mode,' announcing an initial $50 million financing round and officially stepping into the public spotlight. At its debut, international media described Tessera’s Gene Writing technology as capable of doing 'many things CRISPR can do—and also things CRISPR cannot do, such as precisely inserting long DNA sequences.' Jason Pontin, Senior Advisor at Flagship Pioneering, told BioShine: 'Tessera’s Gene Writing platform represents a fundamental advance over existing gene-editing technologies—including Jennifer Doudna and Feng Zhang’s CRISPR systems, and David Liu’s prime editing at Harvard University. Gene Writing allows researchers to literally “write” entire gene fragments into the genome, rather than cutting DNA double-strands or editing single nucleotides.' BioShine contacted Tessera and conducted an exclusive interview. A Super Team Geoffrey von Maltzahn, Ph.D., CEO, Co-Founder, and Director of Tessera, is a General Partner at Flagship Pioneering and holds a Ph.D. in Biomedical Engineering and Medical Physics from MIT. Previously, he co-founded several biotech startups, including cell therapy company Sana Biotechnology, microbial agriculture company Indigo Agriculture, microbiome metabolic therapy company Kaleido Biosciences, and AI-driven biomedicine company Generate Biomedicines. He holds over 200 patents and patent applications. The company also boasts a powerful Scientific Advisory Board. Its Chair is Melissa Moore, Chief Scientific Officer of Moderna. Board members include George Church—pioneer of synthetic biology at Harvard University; Luigi Naldini—an expert in gene therapy from Italy; and David Schaffer, Professor of Chemical and Biomolecular Engineering at UC Berkeley—among others with decades of research experience in gene therapy and gene editing.

Insight | How can biotech startups effectively protect their intellectual property?

Shifting from broad to narrow claims opens the door to developing patentable technology. This strategy is crucial for securing additional protection—and may even impose certain constraints on the first-filed patent. If you’ve already disclosed everything you know, it becomes difficult to iterate and improve upon your invention. At the same time, overly broad patent filings carry risks: if the claimed scope ultimately proves too expansive and easily invalidated, the patent offers no real protection. Companies whose core business centers on R&D can adopt an 'onion-layered' patent strategy. The core of this approach is first filing a patent covering the active pharmaceutical ingredient (API). The next layer might cover formulations that enhance specific physicochemical properties of that API; followed by patents covering delivery routes; and finally, patents covering methods of use for specific indications. As explained: 'This layered structure makes it extremely difficult for competitors to design around the patents and conduct parallel R&D successfully.' 2. Finding Your Own Niche Even within a crowded, high-demand field, carving out a unique niche remains possible. For example, over the past decade, dozens of microbiome-focused companies have launched. Flagship Pioneering entered this space early—founding Seres Therapeutics in 2012 to develop microbiota-based therapies for diseases linked to gut dysbiosis. After investing in Seres, Flagship did not stop there; instead, it continued investing in multiple microbiome startups with distinctive IP. In 2015, Flagship launched Evelo Biosciences—focused on single-strain therapies rather than complex microbial consortia—and Kaleido Biosciences—dedicated to modulating beneficial gut bacteria. In 2017, Flagship formed Ring Therapeutics, targeting symbiotic viruses derived from the gut microbiome to engineer novel gene therapy delivery vectors. In 2020, Flagship merged these four companies to form the prototype of Senda Biosciences, which is now developing a new class of therapeutics: neurologically targeted drugs designed to inhibit gut microbial metabolism—thereby prolonging drug efficacy. Trivinos remarked: 'We engage with startup teams very early, enabling us to grasp the full picture of both the underlying technology and its intellectual property landscape. Some spaces are indeed extremely crowded—but Flagship believes that technological and therapeutic distinctions give each of these four companies a unique perspective within the microbiome field. By recombining them, the new entity has carved out its own distinctive position in this domain. Moreover, even when entering a saturated R&D hotspot, startups can enlist IP experts to identify potential pitfalls and devise licensing strategies—preventing complications down the road. Being a latecomer does not preclude innovation—but caution is essential, since earlier entrants in the same field may claim extraordinarily broad rights.

Flagship Pioneering Merges Three Firms to Launch New Biotech Start-up Etcelera

23 hours ago

Flagship Pioneering merged Cellarity, Empress Therapeutics, and Etiome to form Etcelera, a biotech firm developing drug candidates for blood and immunological diseases using computational biology. One sickle-cell program continues separately while others remain preclinical.

cen

2026-10-29

Flagship Pioneering Merges Three Firms to Launch New Biotech Start-up Etcelera

Flagship Pioneering Merges Three Firms to Launch New Biotech Start-up Etcelera

FAQ