Our approach is guided by our vision to advance patient care, by empowering the healthcare community with effective precision diagnostics.
It’s simple. It’s science. After platelet activation, FcyRIIa on the surface clusters and cross-links. Cross-linking of FcyRIIa leads to downstream signaling and amplification of platelet activation. Platelets from patients with cardiovascular disease exhibit a broad range of FcyRIIa expression on the platelet surface.1,2 Those with high platelet FcyRIIa expression have a consistent stimulus that amplifies platelet activation, promoting thrombosis.
Assessment of Individual Risk of Cardiovascular Events by Platelet FcGammaRIIa
ClinicalTrials.gov Identifier: NCT05175261
This is a Prospective, Observational Multicenter Non-Interventional Cohort Study. The primary objective of the study is to determine whether platelet expression of FcγRIIa is associated with risk of myocardial infarction (MI), stroke and death. The primary endpoint is the composite of death, MI and stroke. A secondary endpoint is the incidence of clinically significant bleeding according to the Bleeding Academic Research Consortium (BARC) scale type 2-5. Approximately 800 subjects with confirmed MI [ST-segment elevation MI (STEMI) or non-ST-segment elevation MI (NSTEMI)] will be enrolled before hospital discharge for the index event. Approximately 20 sites in the United States will participate in this study. It is anticipated that it will take approximately 12 months to enroll approximately 800 subjects.
Platelet FcGammaRIIa and Risk of Venous Thromboembolism in Cancer
ClinicalTrials.gov Identifier: NCT05240508
To investigate a new biomarker of risk in patients with cancer, we propose a pilot study to determine whether quantification of platelet FcɣRIIa expression can discriminate risk of VTE and cancer progression. The proposed studies leverage a clinical research program that was established in 2015 at the University of Vermont Cancer Center (Venous Thromboembolism Prevention in the Ambulatory Care Clinic [VTEPACC]) and will allow simultaneous access to research samples, thrombosis complications and cancer outcomes in order to achieve the following specific aims: 1) To determine whether platelet expression of FcγRIIa identifies cancer patients at high and low risk of VTE, and 2) To determine whether increased platelet expression of FcγRIIa is associated with a) advanced stage cancer at the time of enrollment and b) greater progression of cancer. Identification of a biomarker capable of discriminating high and low risk of VTE will provide an important precision tool that could be combined with existing tools to guide therapy and improve outcomes.
Platelet Expression of FcγRIIa and Arterial Hemodynamics to Predict Recurrent Stroke in Intracranial Atherosclerosis (FCG)
ClinicalTrials.gov Identifier: NCT05518305
This is an observational study whose primary objective is to determine if individuals with increased platelet FcyRIIa will have a higher risk of ischemic events. There are three primary outcome measures: 1) determine the impact of platelet FcγRIIa expression on 1-year risk of recurrent stroke in intracranial atherosclerotic disease (ICAD), 2) quantify the impact of wall shear stress (WSS) from noninvasive CT angiography (CTA) computational fluid dynamics (CFD) on 1-year risk of recurrent stroke in ICAD, and 3) develop a precision model to determine the risk of recurrent stroke 1 year after index events due to ICAD based on individual FcγRIIa expression and WSS from baseline CTA. Approximately 250 subjects who have experienced a stroke or transient ischemic attack (TIA) will be enrolled. Approximately 6 sites in the United States will participate in this study.
The test uses flow cytometry to quantify the number of FcyRIIa molecules per platelet.
Our test is not yet commercially available. It is only available to participants of Prolocor’s clinical studies.
Flow cytometry is a procedure in which blood is added to a tube that contains an antibody to FcyRIIa. The antibody is tagged with a fluorochrome (a chemical that emits light). A laser shines on the sample, and fluorescence is emitted from FcyRIIa. This can be used to quantify the amount of FcyRIIa in 10,000 platelets per minute.
A pilot prospective study showed a significant predictive value of our test in nearly 200 patients with a prior heart attack2-3.
Combining FcyRIIa with clinical risk scores may be very effective for identifying patients at high and low risk of subsequent CV events2-3.
FcyRIIa has three key advantages5 that will be validated in upcoming clinical studies for patients with acute coronary syndrome and chronic coronary artery disease.
FcyRlla Advantage
Low intra-individual variability over the course of a month, regardless of time of day.
Current platelet function tests demonstrate substantial
intra-individual variability.
FcyRlla Advantage
Predicts increased platelet reactivity in response to a variety of agonists.
Current platelet function tests measure platelet reactivity in response to a select agonist or group of agonists.
FcyRlla Advantage
Neither anticoagulants nor a P2Y12 antagonist alter platelet expression of FcyRIIa.
Current platelet function tests are very sensitive to assay conditions.
Platelet FcγRIIa as a Marker of Cardiovascular Risk After Myocardial Infarction
Journal of American College of Cardiology (2024)
Association Between Prognostic Implications of Platelet FcɣRIIa (pFCG) and Treatment Strategy for Myocardial Infarction (MI)
ACC.24: American College of Cardiology Scientific Session (2024)
Exploring the potential cost-effectiveness of a novel platelet assay for guiding dual antiplatelet therapy duration in acute coronary syndrome patients following percutaneous coronary intervention
Coronary Artery Disease (2023)
Platelet FcYRIIa Expression in Ischemic Stroke: A Marker of Increased Platelet Reactivity
Stroke: Vascular and Interventional Neurology (2022)
Assessment of Cardiovascular Risk by the Combination of Clinical Risk Scores Plus Platelet Expression of FcYRIIa
The American Journal of Cardiology (2020)
Variation in Platelet Expression of FcYRIIa after Myocardial Infarction
The Journal of Thrombosis and Thrombolysis (2019)
Augmentation of Megakaryocyte Expression of FcYRIIa by Interferon Y
Arteriosclerosis, Thrombosis, and Vascular Biology (2009)
references
Schneider D, et al. Stroke: Vascular and Interventional Neurology 2022;2(3).
Schneider D, et al. J Am Coll Cardiol 2018;72:237-238.
Schneider D, et al. Am J Cardiol 2020;125:670-72.
Yeh RW, et al, JAMA 2016;315:1735-1749.
McMahon SR, et al. Journal of Thrombosis and Thrombolysis 2019;48:88–94.
