City Therapeutics, founded on Kotaro Nakanishi’s Ohio State research, secures $1 billion collaboration with Biogen

Biogen is investing up to $1 billion in a new research collaboration with City Therapeutics, a biotechnology company founded on discoveries made at The Ohio State University. The agreement includes $46 million in upfront and equity funding and could deliver hundreds of millions more in milestone payments as the company advances next-generation RNA interference (RNAi) therapies.

City Therapeutics is based on research by Kotaro Nakanishi, professor in the Department of Chemistry and Biochemistry in the College of Arts and Sciences. His lab discovered that a short strand of RNA—just 14 nucleotides long—can silence genes as effectively as the longer strands typically used in RNAi therapy (Cell Reports, Zhang et al., 2024). The breakthrough improves the potential for delivering RNA-based drugs to areas like the brain, where traditional therapies often fall short.

“In our field, people used to believe that only a full-length guide RNA could work,” Nakanishi said. “But we showed that a shorter guide RNA could do the job. That changes what’s possible for delivery to the brain and other challenging tissues.”

RNAi is a natural biological process where short pieces of RNA can turn off genes linked to disease. The molecules developed in Nakanishi’s lab—called cityRNAs (cleavage-inducing tiny RNAs; PNAS, Park et al., 2020)—are smaller, more stable and easier to deliver. This makes them particularly promising for treating conditions like Alzheimer’s disease and ALS.

The agreement gives Biogen access to develop RNAi-based therapies using City’s platform for select neurological targets. City Therapeutics retains the rights to its broader RNAi discovery pipeline.

“This started as basic research—just trying to understand how RNA interacts with proteins inside the cell,” Nakanishi said. “We weren’t chasing a product. We were chasing knowledge. And now it’s become something that could help people in the real world.”

Susan Olesik, dean of the College of Arts and Sciences, said the agreement represents the high value of investing in faculty-led research.

“Professor Nakanishi’s work is a shining example of how curiosity-driven science can lead to tangible, high-impact outcomes,” Olesik said. “We are proud to see innovation from our faculty playing a role in addressing some of the most complex medical challenges of our time.”

Kevin Taylor, chief innovation officer at Ohio State, said the Biogen partnership reflects the university’s growing capacity to support the commercialization of transformational research.

“This collaboration shows what’s possible when we support breakthrough research with the tools needed to bring it to market,” Taylor said. “City Therapeutics represents a successful example of that pipeline—from lab discovery to license to a high-potential startup company to its first major industry collaboration.”

For Nakanishi, the partnership represents both scientific validation and personal fulfillment.

“Biogen brings world-class expertise in neurodegeneration,” he said. “We bring world-class RNAi innovation. Together, I believe we can turn what was once impossible into reality.”