CRISPR Expands Focus, Pays Up To $95M in Sirius’ siRNA Pact

 

The partnership with Sirius expands CRISPR Therapeutics’ modality toolkit, especially in the cardiovascular space.

CRISPR Therapeutics is looking to diversify its therapeutic toolbox, partnering with Sirius Therapeutics to co-develop an investigational siRNA therapeutic for thromboembolic disorders in a deal announced Monday.

As per Monday’s agreement, CRISPR will make a modest $25 million upfront payment in cash to Sirius, alongside a $70 million equity investment. In exchange, CRISPR will have the right to co-develop SRSD107, a next-generation and long-acting siRNA therapy that targets Factor XI, a central player in the formation of pathological blood clots.

Writing to investors early on Tuesday, analysts at William Blair said they “view the collaboration positively” since it “provides additional synergies for CRISPR’s cardiovascular pipeline.” The move, they added, expands CRISPR’s pipeline “beyond ‘one and done’ therapies,” like the company’s flagship treatment Casgevy, and further deepens “a robust and . . . underappreciated pipeline.”

Phase I data, revealed by CRISPR in its news release on Monday, show that SRSD107 could reduce Factor XI levels by over 93%, while also more than doubling activated partial thromboplastin time, a measure of how long blood takes to clot. Early-stage data also support the safety and tolerability of SRSD107, according to CRISPR.

CRISPR and Sirius will jointly develop SRSD107 and split costs and profits 50-50. CRISPR will take charge of commercialization in the U.S., while Sirius will lead market efforts in the Greater China region. The partners are preparing to launch a Phase II trial of SRSD107 in patients undergoing total knee arthroplasty.

SRSD107’s mechanism of action could also open up its use in other patient populations, including those with cancer-associated thrombosis, coronary artery disease and venous thromboembolism, as per CRISPR’s announcement.

Monday’s pact also allows CRISPR to nominate up to two additional siRNA targets, for which it will fund R&D activities and have opt-in rights to take over clinical development and commercialization. For these programs, Sirius will be entitled to certain milestones and tiered royalties.

The Sirius partnership comes as CRISPR gears up for a few key milestones this year. In its cardiovascular portfolio, for instance, the biotech is awaiting data for its in vivo therapy CTX320, which William Blair in its Tuesday note branded as a “major near-term catalyst” for the company. CTX320 is being studied in patients with elevated lipoprotein(a) levels, with a readout expected in Q2.

CRISPR is also expecting data for its off-the-shelf CAR T program CTX112, which it is studying in autoimmune conditions, by mid-2025.

https://www.biospace.com/business/crispr-expands-focus-pays-up-to-95m-in-sirius-sirna-pact