Tessera Therapeutics stacks up more than $300M in series C funds to bolster new gene-editing platforms

Tessera Therapeutics, founded and created by life sciences VC staple Flagship Pioneering, is building a war chest with a fresh $300 million for its trio of gene writing platforms.

The latest fundraising round, announced Tuesday, brings the company’s total haul to more than $500 million over the last 15 months. The investors this round included a couple of government investment funds, Alaska Permanent Fund Corporation and Abu Dhabi Investment Authority. 

The brainchild of Geoffrey von Maltzahn, Ph.D., Jacob Rubens, Ph.D., and Flagship co-founder and CEO Noubar Afeyan, Ph.D., Tessera was founded in 2018 but didn't unveil itself until 2020. A year later, it catapulted forward with $230 million in fundraising.

It’s just the latest venture for von Malzhan, whose prior companies include Generate Biomedicines, Seres Therapeutics and Kaleido Biosciences. Kaleido shuttered earlier this month after its microbiome-focused pipeline sputtered. As for Tessera, von Maltzahn says that the latest funding haul will allow the company to realize its initial vision as it moves toward the clinic. 

“We’re going to be advancing in a sense a portfolio of portfolios, with each of the gene writing categories enabling their own portfolio of therapeutics, and Tessera being home to the aggregate of those portfolios,” he said in an interview with Fierce Biotech. The company has not said which diseases it's targeting but has signed an R&D pact with the Cystic Fibrosis Foundation. Von Maltzahn also hinted that the company's technology could have value in the liver. 

Von Maltzahn’s concept is founded on mobile genetic elements (MGE), segments of DNA that code for enzymes and proteins that help move DNA around within genomes. Emblematic of his confidence, von Maltzahn referred to MGEs as a “wonder of the world.”

Tessera's platforms focus on three things: RNA gene writers that can make short, quick edits, whether insertions or deletions; larger RNA templates that can "grab onto a genome" and write RNA into a full-length gene; and lastly, DNA gene writers that can be pasted into specific locations within a genome. 

By pursuing all three at once, von Maltzhan hopes to create a “technology meritocracy” whereby development of a new asset naturally flows toward the platform where it fits best. He wouldn’t specify how that meritocracy is playing out in terms of current investment. But as gene editing grows, it’s important to cover your bases in pursuit of perfection, he said.

“Nobody is going to be able to hide from their weaknesses,” he said. “And we don’t think physicians are going to prescribe the fourth-best genetic medicine if it has knowable limitations to the best.”

Now armed with more than half a billion dollars, Tessera is looking to grow in all directions, not just in asset development. In addition to getting to the clinic, the company plans to keep “aggressively investing in the platform,” set up its own manufacturing operation and grow the team, which currently sits north of 200 people. In terms of manufacturing, von Maltzahn said the company is building out capacity over the course of this year to handle its first clinical indications. 

“We’re being careful about how much we spend there, but it is really important to us to be able to own our manufacturing,” he said, adding that he hopes to be operational within the next 18 months. 

Given the breadth of possibilities that Tessera’s platform could unlock, von Maltzahn acknowledged that “the technologies will enable more than we could prosecute ourselves.” As a result, the company is open to a “likely smallish number” of partnerships.