Silk Road reels in $57M to commercialize its system for stroke prevention

Silk Road Medical's Enroute Transcarotid Neuroprotection system--Courtesy of Silk Road Medical

Devices to treat stroke are en vogue, and so are those to prevent it, as demonstrated by the $57 million debt and equity financing of Silk Road Medical, maker of an FDA-approved system to treat carotid artery blockages in the neck, a risk factor of the often-fatal condition.

New investor CRG led the debt financing, and also participated in the equity round, alongside returning investors Warburg Pincus and The Vertical Group.

In February, Silk Road earned FDA clearance for its Enroute Transcarotid Neuroprotection System, which enables the insertion of a catheter into the artery in the neck, instead of through the groin and up the leg's femoral artery, reducing surgical risks and potential complications associated with more invasive procedures

In addition, the device protects the brain during carotid artery angioplasty and stenting by temporarily reversing blood flow and carrying away debris in the blood stream. The blood is then filtered externally and returned to the body via a vein the leg, the FDA explained in a statement upon the clearance. The standard of care is to use an internal filter or additional balloon to capture and remove debris in the blood.

And in May, the FDA gave PMA approval to the stent used in conjunction with the neuroprotection system. The stent helps the carotid artery stay open following the procedure, and was based on a similar device designed by Cordis, now owned by Cardinal Health ($CAH).

Silk Road plans to use the latest round of financing to continue commercialization of the stent and neuroprotection system in the U.S., build out evidence in support of so-called transcarotid artery revascularization (TCAR) procedures and begin international expansion, according to a release.

"The strength of this financing is a testament to the large opportunity we have to solve unmet clinical needs and lead the next endovascular revolution with TCAR," Silk Road CEO Erica Rogers said in a statement. "Our proprietary advances in temporary, robust flow reversal technology and transcarotid catheter designs help physicians treat this unforgiving disease in a minimally invasive manner with low risk of procedural complications like stroke, heart attack and nerve injury."

Silk Road says more than 400,000 cases of carotid artery disease are diagnosed per year in the U.S.; 125,000 require operations, which are often invasive surgeries, not the minimally invasive option enabled by the company's devices. The NIH says the disease is responsible for more than half of the strokes in the U.S.

"Carotid artery disease is the last frontier in vascular medicine, "said Bess Weatherman, managing director of healthcare at Warburg Pincus, in a statement. "Until Silk Road, we had yet to see a minimally invasive technology that could stand up to the challenge of this disease. The Company's paradigm-shifting technology platform is led by an accomplished management team with the support of world-class physicians who are together modernizing carotid artery repair for the benefit of patients. Following Silk Road's outstanding clinical results, we are excited to continue partnering with the team to bring this faster, safer, less invasive and more effective neurovascular procedure to market."

- read the release