The U.S. Patent and Trademark Office (USPTO) has granted Sherlock Biosciences a patent for the diagnostic use of the Cas12 enzyme, which established the company as a provider of CRISPR-based diagnostics in the U.S.

Sherlock has exclusive U.S. rights to the patent from Shanghai-based Tolo Biotech, plus additional intellectual property (IP) for Cas12 and Cas13 from the Broad Institute, giving the company a solid IP position in the space, the company says.

The newly granted patent covers a method for detecting nucleic acids leveraging the collateral cleavage activity of Cas12. Unlike Cas9—the enzyme commonly used for gene editing and CRISPR-based therapeutics, and the subject of several patent disputes—Cas12 is best suited for detecting DNA and RNA sequences, rather than editing them. Sherlock and its academic co-founders have already demonstrated the potential for flexible, high-accuracy, low-cost Cas12-based detection of diseases, including malaria, tuberculosis, and COVID-19.

Further reading: A Closer Look at CRISPR Technology & The Clinical Lab

“Sherlock’s diagnostic tests have the potential to transform the healthcare paradigm by shifting power to consumers. Securing this patent is an important step to deliver powerful, over-the-counter diagnostics so consumers have more control over their healthcare decisions,” says Bryan Dechairo, president and CEO of Sherlock Biosciences. “Our diagnostics rely on novel uses of synthetic biology and CRISPR technology to condense the traditional lab tools into handheld tests. With this patent, on top of our existing agreement with Tolo granting co-exclusivity to Cas12 globally, we have secured our dominant IP position with the most comprehensive portfolio of diagnostic CRISPR patents.”

CRISPR-Based Diagnostics

Sherlock’s CRISPR-based diagnostics rely on a key pair of technologies to detect diseases, covered by the patent: amplification and collateral cleavage. First, a specific nucleic acid signature is amplified so that the guide RNA can find and recognize it within a test sample. Once the guide RNA identifies and binds to the target nucleic acid, the Cas12 enzyme becomes activated and cleaves a fluorescently labeled probe present in the mixture. This cleavage event triggers a reaction which then leads to the release of a fluorescent signature, indicating a positive test. 

“With this patent, Sherlock has a clear, unimpeded pathway to commercialization for our CRISPR-based diagnostics,” says Jim Collins, PhD, co-founder and board member of Sherlock Biosciences. “The pairing of proprietary amplification technology from the Wyss Institute, as well as the rapid molecular amplification chemistry gained through our recent acquisition of Sense Biodetection, puts us on track to become a global health leader. This dominant and defensible patent position will allow us to establish the necessary market foothold in the U.S. before we bring our rapid, point-of-need diagnostic tests to the rest of the world.”