AHA: HDL Therapeutics' cholesterol-enriching procedure cuts coronary plaque in rare genetic disorder

Treatments for high cholesterol stemming from a rare genetic disorder focus on lowering patients’ LDL, or “bad” cholesterol and delaying disease progression. HDL Therapeutics is looking to go further: it is working on a treatment made from a patient’s own HDLthe “good” cholesterolto not just stave off heart disease, but to reverse damage to the heart’s coronary arteries.

(Courtesy of HDL Therapeutics)

The Vero Beach, Florida-based devicemaker announced data from a registrational study of its PDS-2 device in six people with homozygous familial hypercholesterolemia, or HoFH. To be presented at the annual meeting of the American Heart Association, the data showed that the treatment, which involves enriching a patient’s plasma with a certain kind of “good” cholesterol, reduced the buildup of plaque by 18% in coronary arteries after seven weeks. The study also found that the treatment reduced the size of two of the most dangerous kinds of plaques: necrotic core and low-density plaques.

“Because of the imaging techniques we used, we were able to characterize plaque and focus on the highest-risk plaques that are vulnerable and tend to rupture and cause events,” CEO Michael Matin told FierceBiotech. “For us to show a 38% reduction in low-density and a 33% in necrotic core plaques... is quite dramatic. We know of no other therapy currently available on the market or in development with these kinds of results.” 

People with HoFH are often diagnosed in childhood or adolescence and have very high levels of “bad” cholesterol. They develop heart disease at a very young age, typically before they turn 20. Current treatments include statins and other cholesterol-busting drugs, but these don’t work in many people with HoFH. 

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CEO Michael Matin
(HDL Therapeutics)

“It turns out that HDL, or 'good' cholesterol is not uniformly good. There are two main subtypes: pre-beta and alpha HDL,” Matin said.  

HDL’s PDS-2 device “turbocharges the body’s own biology to fight heart disease,” Matin said, by turning alpha HDL into pre-beta HDL.

He likens both to dump trucks. Pre-beta HDL is an empty dump truck that collects and removes lipids from the walls of blood vessels. Once it's full, it becomes alpha HDL, which hauls its cargo to the liver where excess lipids are eliminated. The problem is that there aren’t enough naturally occurring empty dump trucks to attack the plaque buildup in people with HoFH.

That’s where PDS-2 comes in. Patients come into a clinic, hand over a bag of plasma and let the machine do its work. The enriched plasma is infused back into the patient, where the pre-beta HDL will remove lipids from plaques. The approach would complement lipid-lowering meds in an approach that would lower “bad” cholesterol and reverse the cardiovascular damage it does.

HDL Therapeutics is planning to bring the treatment to market solo, but if a “collaboration with a strategic partner will be able to accelerate getting this therapy to patients with homozygous FH, we would happily consider it,” Matin said. 

“Homozygous FH is the most severe form of atherosclerosis. Patients have premature heart attacks and strokes and they typically exhibit the kinds of symptoms in the first two decades of their lives that patients with normal heart disease will demonstrate in the last two decades of their lives,” he said. “For us to be able to rapidly regress the highest-risk plaques speaks to the power and potential of this therapy in the field of atherosclerosis.”