Study Investigates Feasibility and Potential of the PlaqueTec LBS to Detect Biomarkers for CAD

January 5, 2018—PlaqueTec Ltd. announced the publication of findings demonstrating the feasibility and potential of its PlaqueTec liquid biopsy system (LBS) to detect biomarkers for coronary artery disease (CAD). The results are from the first-in-human studies of the LBS in detecting biomolecular gradients in diseased coronary arteries of symptomatic patients undergoing percutaneous coronary intervention procedures.

According to the company, the PlaqueTec LBS is a dedicated liquid biopsy catheter approved in the European Union for collecting biomarkers directly associated with plaques within coronary arteries, as a means to assess and potentially resolve residual inflammatory risk. The system draws blood samples from the "boundary layer," close to the vessel wall, where biomolecules released from plaques are likely to be most concentrated. It can also detect small gradients of released molecules by simultaneously collecting blood both upstream and downstream of individual plaques. The product is not approved for use in the United States.

The study by Nick E.J. West, MD, et al is available online in Journal of the American College of Cardiology [JACC]: Basic to Translational Science. Dr. West, who is an interventional cardiologist at Papworth Hospital in Cambridge, United Kingdom, serves as Chief Medical Officer of PlaqueTec. The company was formed in 2008 at Papworth Hospital as a spinout from PA Consulting.

In the company's announcement, Dr. West commented, "The LBS fills an unmet clinical need to detect coronary atherosclerotic plaques that are likely to rupture and therefore precipitate acute coronary syndromes. This innovative catheter enables, for the first time, the definition of a biochemical signature for vulnerable plaques in living patients. Our experiments suggest that the LBS may facilitate identification of prognostic biomarkers and development of surrogate endpoints for future clinical trials."

As summarized by the company, investigators analyzed data from the first-in-human safety and feasibility study and the first human proof-of-concept evaluation of the LBS (N = 58). The LBS was used as an adjunct to coronary angioplasty and stent deployment in patients with stable angina pectoris or stabilized non–ST-segment elevation acute coronary syndromes.

The investigators reported that deployment of the LBS into unobstructed coronary arteries and its use in taking four simultaneous blood samples was shown to be feasible and safe in patients undergoing angioplasty to a target in a different coronary artery. In unobstructed vessels with no lesion, the investigators observed no significant gradients of 92 biomolecules involved in the CAD process. In contrast, they observed statistically significant gradients of bioactive molecules across intact and disrupted atherosclerotic plaques, implying the release of substances from plaques into the boundary layer of the vessel. The investigators detected several inflammatory mediators, consistent with the inflammatory status of the endothelium.

After angioplasty, the investigators observed the release of additional substances, including matrix metalloproteinase-12 (MMP12), which is normally undetectable in endothelial cells or smooth muscle cells and expressed only around the core of vulnerable plaques. Because of the causative role of MMP12 in early strokes and its association with subsequent strokes and major adverse events, the investigators surmised that the postangioplasty gradient of MMP12 may yield important diagnostic or prognostic information, stated the company.