Alnylam, Vir team up to develop siRNAs to tackle COVID-19

Alnylam Pharmaceuticals and Vir Biotechnology have teamed up to develop RNAi therapeutics against the coronavirus behind the COVID-19 outbreak. The collaboration builds on Alnylam synthesis of siRNAs that target highly conserved regions of coronavirus RNA.

Vir and Alnylam joined forces to develop up to six siRNAs against infectious diseases in 2017, leading to the initiation of a clinical trial of a hepatitis B candidate. The coronavirus collaboration expands on that existing agreement and gives the partners the chance to pool their resources to develop siRNAs with the potential to tackle the virus.

Alnylam has synthesized more than 350 siRNAs targeting all available genomes of SARS-CoV-2—the virus at the heart of the outbreak—and SARS-CoV. The partners claim some of the siRNAs hit highly conserved regions of RNA, suggesting they may be broadly efficacious against coronaviruses.

Encouraged by those early data, the partners plan to put the siRNAs through in vitro potency assays. Vir will then perform in vitro and in vivo assessments of the antiviral activity of the most promising, potent prospects with a view to selecting a development candidate.

Vir will remain in charge up to clinical proof of concept. At that stage, Alnylam will have the option to either share the costs and profits of further development and commercialization or to stay on the sidelines while earning milestones and royalties tied to the progress of products resulting from its early siRNA work.

While Vir is set to take the lead on the project, at least in its early stages, the prospect of creating siRNA therapies that are effective against SARS-CoV-2 is made possible by Alnylam. Specifically, the collaboration will leverage Alnylam’s work on delivering siRNA conjugates to the lung. 

As with some of the other efforts to tackle SARS-CoV-2, such as Moderna’s mRNA vaccine project, the technology behind the Alnylam-Vir collaboration is experimental. Alnylam trialed an aerosolized siRNA drug as a treatment for respiratory syncytial virus infection years ago, but progress stalled after a phase 2b trial missed its primary endpoint.

The RNAi specialist bounced back to become the first company to win FDA approval for an RNAi therapeutic in 2018. However, that drug, like many others in Alnylam’s pipeline, targets the liver, the prime location for RNAi therapeutics. To tackle SARS-CoV-2, Alnylam will need to show it can expand past the liver.

Vir thinks that is possible. George Scangos, who is leading BIO’s coronavirus response while serving as CEO of Vir, explained how Alnylam’s technology fits into his company’s efforts to tackle COVID-19 in a statement. 

“Given the scope and speed of the COVID-19 outbreak, Vir is seeking multiple approaches that combine our expertise in infectious disease with that of current and new partners to respond rapidly. Alnylam has been an excellent partner, and our complementary capabilities made this a compelling opportunity to address this growing public health crisis,” Scangos said.