Alnylam announces $250M expansion to add enzymatic ligation manufacturing

Alnylam Pharmaceuticals, a Cambridge, Massachusetts-based RNA interference therapeutics company, said it plans to invest $250 million to expand its manufacturing facility in Norton, Massachusetts, adding what the company described as the industry’s first fully dedicated proprietary enzymatic ligation platform for siRNA production.

According to the announcement, the expansion will significantly increase manufacturing capacity and lower production costs for RNAi therapeutics, supporting future launches across its growing pipeline. 

The project centers on Alnylam’s siRELIS enzymatic ligation platform, which the company said has been accepted into the U.S. Food and Drug Administration’s Emerging Technology Program, accelerating regulatory engagement for the novel manufacturing approach.

CEO Yvonne Greenstreet in a statement said the expansion will be a “critical enabler” in expanding the company’s pipeline of RNAi therapeutics and accelerating the development of siRNA manufacturing.

The company’s expansion will build on its 200,000-square-foot Norton facility, which opened in 2021 and produces both clinical and commercial supplies of siRNA drug substance. Construction is underway, with new capabilities expected to be fully operational by late 2027, according to the company.

Alnylam said the enzymatic ligation platform has already been demonstrated through pilot-scale production of zilebesiran and nucresiran — investigational RNAi therapeutics currently in development.

“Manufacturing oligonucleotide-based medicines is highly complex, and the current manufacturing technology will struggle to meet increased demand,” Timothy Maines, CTO and quality officer at Alnylam, said in a statement. “We have successfully applied a reproducible, less time-intensive process that increases throughput while maintaining the highest quality standards.”