Gene Writing Platform Secures $230M+ to Transform Genetic Medicine—Tessera Therapeutics' Bold Bet on DNA Reprogramming

Tessera Therapeutics has closed a substantial Series B funding round exceeding $230 million, marking a significant milestone for the emerging biotech company’s mission to revolutionize genetic medicine through its proprietary Gene Writing technology. The financing round was jointly led by Alaska Permanent Fund Corporation and Altitude Life Science Ventures, with participation from SoftBank Vision Fund 2, Qatar Investment Authority, and additional institutional backers.

What Sets Gene Writing Apart: Breaking the Limits of Current Genetic Approaches

Unlike conventional gene editing and gene therapy methods that face inherent constraints, Tessera Therapeutics’ Gene Writing platform operates on a fundamentally different principle. The technology enables precise modifications to the human genome—substituting individual base pairs, making targeted insertions or deletions, and inserting entirely new genetic sequences—all while avoiding the double-strand breaks characteristic of nuclease-based editing tools.

The platform draws inspiration from nature’s mobile genetic elements, which Tessera’s team has systematized into an engineered approach. Using computational design and high-throughput laboratory methods, the company has developed the ability to synthesize and test thousands of modified genetic elements, effectively creating a toolkit for rewriting specific genomic instructions.

A critical advantage emerges in cellular durability: Gene Writing can permanently integrate new DNA into dividing cells—a capability that AAV-based gene therapy approaches cannot match. Additionally, the platform achieves genome modification by delivering only RNA, eliminating the need for complex viral vectors or reliance on cellular repair mechanisms.

Expanding the Disease Horizon: From Neurodegenerative Conditions to Oncology

The therapeutic potential spans multiple disease categories—cardiovascular disorders, cancer, neurodegenerative conditions, and infectious diseases all present potential targets. By enabling physicians to correct genetic defects at their source, Gene Writing positions itself as a new category within genetic medicine rather than an incremental advancement of existing approaches.

Geoffrey von Maltzahn, CEO and Co-Founder of Tessera Therapeutics, framed the technology’s significance: “The ability to write into the genetic code represents a defining innovation of this era. Our investor coalition recognizes that this platform can translate into transformative treatments for patients facing previously untreatable genetic conditions.”

Flagship Pioneering’s Strategic Commitment and the Broader Ecosystem

Noubar Afeyan, Chairman and Co-Founder of Tessera Therapeutics and leader of Flagship Pioneering, increased the parent organization’s capital contribution to $60 million. This move underscores Flagship’s confidence in Gene Writing while reflecting the firm’s broader strategy of developing nucleic acid-based therapeutics—a category that includes messenger RNA platforms, engineered viral vectors, and epigenetic modulators.

Flagship Pioneering operates a portfolio of over 40 active biotech ventures, including publicly traded companies like Moderna, Denali Therapeutics, Evelo Biosciences, and Seres Therapeutics. The ecosystem demonstrates a track record of generating $50 billion in aggregate value since the firm’s 2000 inception.

Capital Deployment: Accelerating Clinical Readiness

Tessera Therapeutics intends to deploy the new capital toward advancing multiple therapeutic programs toward clinical development, scaling its research infrastructure, and establishing manufacturing and automation systems critical for platform commercialization. The funding trajectory positions the company to validate Gene Writing’s efficacy across diverse disease targets and move from proof-of-concept to human trials.

The Series B represents investor validation of both Tessera Therapeutics’ scientific approach and the commercial viability of Gene Writing as an entirely new therapeutic modality—one that could address genetic diseases previously considered beyond the reach of current biotechnology.