Sentien heads to clinic with blood conditioning device for renal failure

Sentien's trial will enroll approximately 24 patients requiring renal replacement therapy.

Massachusetts biotech Sentien has filed for approval to start clinical trials of a blood filtering device packed with bone marrow cells for severe cases of acute kidney injury (AKI).

It will be the first clinical trial for Sentien, which was formed in 2008 but has been flying pretty much under the radar until this year. Now, thanks to a $12 million first-round fundraising (PDF), the company is ready to press ahead with a phase 1/2 trial of lead device SBI-101 that should start later this quarter, according to co-founder Biju Parekkadan.

Parekkadan told FierceMedicalDevices that so far attempts to develop therapies for AKI based on small-molecule drugs, biologic drugs or cell therapies have been unsuccessful. The only management option for severe AKI cases remains renal replacement therapy, which includes hemodialysis and blood filtration.

SBI-101 is based on mesenchymal stromal cells (MSCs), a form of stem cell thought to secrete a range of anti-inflammatory and regenerative factors. The device can slot into the equipment used for renal replacement therapy so that patients can receive the blood conditioning therapy and dialysis in a single session.

The device works ex vivo—so no cells need to be injected into the patient—and the system "allows for controlled, sustained and dynamic interaction of MSCs and a patient's bloodstream to invoke a durable wound healing response throughout the entire body without direct cell injection," according to Parekkadan.

Sentien is looking at using MSC-laden devices for a number of indications, including acute liver injury and to aid recovery after a heart attack, but as AKI is such a large and serious problem and already relies on ex vivo blood treatment, it seemed the best option to road-test the technology.

Also called acute renal failure, AKI is a rapid loss of kidney function that can be caused by multiple factors. It is estimated to occur in anywhere between 5% and 20% of hospitalizations in the U.S. and has a high mortality rate, reportedly higher than 50% for severe cases, and survivors are at risk of requiring lifelong dialysis or a kidney transplant.

"Single factor medications have shown to be ineffective for AKI because they fail to address the multi-factorial pathophysiology of the disease," said Parekkadan. Some organizations—including biotech AlloCure—have tried to use MSCs infused directly into patients as therapy, but although the therapy appeared to be safe they were unable to show efficacy, he added.

Applying the cell therapy outside the body has two advantages over MSCs administered via injection or intravenous infusion, he said. The duration of activity is longer—extended from about an hour with infused cells to 24 hours or more—and the maximum number of cells that can be brought into play is much higher, overcoming dosage limitations.

"In essence, our product enables a tunable control of both the cell mass and duration of exposure to a cell therapy without concern of the cells entering the body," said Parekkadan. "Based on what we have tested pre-clinically, we can increase the exposure of the patient to MSCs by more than 1000-fold."

Sentien's study will enroll about 24 patients with AKI that is severe enough to require renal replacement therapy, with recruitment likely to continue through 2017 and into 2018. The primary objective will be to evaluate the safety and tolerability of SBI-101, but the study will include some endpoints for efficacy.