Eleven Therapeutics Receives $3.9 Million for Development of Innovative Treatments Against Respiratory Viruses

Eleven Therapeutics
4 min readMar 9, 2022


The funding was received from the Bill & Melinda Gates Foundation and is directed at the development of durable siRNA cocktails against respiratory pathogens for affordable and deployable prophylaxis

July 1st, 2021
TEL AVIV, ISRAEL and CAMBRIDGE, U.K. — Eleven Therapeutics, a biotechnology company leading the AI revolution in nucleic acid therapies, announced today that it has secured a $3.9 million grant from the Bill & Melinda Gates Foundation, aimed at developing siRNA treatments against respiratory viruses.

The program is powered by Eleven Therapeutics’ groundbreaking Sens.AI platform, and its aim is the development of a novel type of prophylaxis against respiratory RNA viruses, such as the flu and SARS-CoV-2: a nasal spray containing a cocktail of siRNA therapeutics. The nasal spray siRNA cocktail is intended to create a hostile environment for the virus in the respiratory tract. The treatment complements existing vaccines, which are successful at preventing hospitalization and death, but provide only a short protection against transmission and are vulnerable to escape mutations. Notably, rather than solely targeting the spike protein, like the vaccines do, the siRNA prophylactic is designed to target conserved regions in the viral genome that are not exposed to antibodies, which makes it resistant to immune escapes. It can therefore serve as both a prophylactic solution during the dynamic phases of the pandemic, as well as an ideal weapon for future pandemic preparedness programs.

“We are extremely excited about this funding,” said Yaniv Erlich, Chief Executive Officer of Eleven Therapeutics, “because it enables us to make our breakthrough discoveries rapidly available to people in need, including in developing countries. Existing vaccines are widely successful, but we must expand the range of prophylactic solutions, as it is evident that vaccines alone don’t cut it. Preventing transmission is proving to be key in this pandemic because transmission is the gateway to continuous mutations that yield new and dangerous variants. Additionally, unlike existing mRNA vaccines, the siRNA cocktail in development does not require cold-chain distribution, so that these treatments are far more accessible to at-risk populations around the world.”

The Gates Foundation grant partially funded a groundbreaking therapeutic development project, during which researchers at Eleven Therapeutics focused on identifying hyper-potent siRNA molecules. Using Sens.AI, Eleven’s main discovery algorithm, they tiled the SARS-CoV-2 genome and identified and synthesized 16,471 potential safe RNAi triggers. Using its proprietary massively parallel bio-engineered screening platform, the team selected the top ten most potent molecules for advanced, live-virus experiments. Next, the team tested 14 cocktail combinations, four of which showed synergistic effects beyond mono-therapy with the top-performing siRNA. Potency was established at a single-digit picomolar range, regardless of the viral strain it was tested against. Progressing at record development speeds, the team demonstrated success through the gold-standard Syrian hamster model of SARS-COV-2. The in vivo experiments were conducted by the Vaccine Research Center of NIAID as part of a Cooperative Research and Development Agreement (CRADA).

The new funding will allow Eleven Therapeutics to use Sens.AI for the purpose of finding hyper-potent siRNAs against Influenza and to mature and accelerate the SARS-CoV-2 program.

“Our preliminary findings show that it is possible to identify broad and potent siRNA molecules against conserved regions in multiple pathologic influenza strains,” said Dr. Adi Na’amati, who leads the respiratory disease discovery efforts at Eleven Therapeutics. “Using this approach, we will usher in a novel type of prophylaxis that is specifically apt at protecting vulnerable populations, such as the elderly and the immunocompromised.”

About Eleven Therapeutics

Eleven Therapeutics ushers in the next generation of RNAi therapeutics by combining artificial intelligence (AI), massively parallel functional assays, and combinatorial chemistry. Its flagship invention features a new modality, dubbed SCSI-RNA™ (single-chassis, small interfering RNA), a fully programmable molecule, rationally designed to address the delivery, durability, and efficacy challenges of any disease and biological target of interest. Founded in 2020 by a group of globally-leading, interdisciplinary scientists, Eleven Therapeutics brings new RNAi therapeutics for patients in need by capitalizing on some of the world’s best pools of talent through its three collaborative hubs — in Cambridge, UK; Boston, U.S.; and Tel Aviv, Israel. Eleven is currently focusing its development pipeline on siRNA treatments for a range of respiratory diseases. To learn more, visit www.eleventx.com.


Eleven Therapeutics

Prof. Yaniv Erlich
Chief Executive Officer and Co-Founder
Email: yaniv@eleventx.com