,

Coagulation Tests Find Use in COVID-19, New Anticoagulants

Kalorama’s new study on hematology and coagulation finds increased uses of coagulation testing  to determine COVID-19’s unfortunate effects on the blood health of patients.

Coagulation is a complex process in which multiple enzymes and proteins regulate blood flow and clot formation. Coagulation (clot formation), fibrinolysis and platelet aggregation are a part of this process. Fibrinolysis refers to the breakup of blood clots. It is a normal body process that keeps naturally occurring blood clots from growing and causing problems. Anticoagulant drugs help prevent blood platelets from sticking or clumping together, reducing the likelihood that arteries will be blocked by a clot, leading to a stroke or heart attack.

The most widely used drug is Coumadin (Warfarin) that is prescribed for patients with atrial fibrillation, artificial valves and phlebitis. People on warfarin need to have their blood monitored regularly (sometimes weekly and sometimes monthly) to ensure that they are taking the right dosage to avoid clotting if the dosage is too low and also unintentional bleeding when the dosage is too high. This is done with a blood clotting test known as the International Normalized Ratio (INR, formerly known as the
Prothrombin Time test). Proponents of self-testing claim that daily or weekly testing at home helps patients maintain better anticoagulant activity – not too much and not too little.

There are newer oral anticoagulants on the market, such as rivaroxaban (Xarelto), apixaban (Eliquis) and dabigatran (Pradaxa). They are at least as safe and effective as warfarin, and they do not require regular coagulation monitoring with a PT/INR. However, hematologists will use immunoassays to measure the amount of drug concentration in a patient’s blood to assure that the amount of drug is in the therapeutic range. This is akin to therapeutic drug monitoring by immunoassay of antibiotics (gentamicin), antiepileptics (such as carbamazepine, phenytoin and valproic acid), and antipsychotics (such as pimozide and clozapine).

Patients with atrial fibrillation and artificial valves are beginning to switch from warfarin to next-generation drugs. Pharmaceutical companies have heavily invested in direct-to-consumer advertising efforts, ultimately extolling the benefits of these drugs. At this time, this provides another test opportunity in coagulation testing. Several companies have already commercialized tests for the monitoring of the new anticoagulant drugs.

Coagulation testing, including d-dimer, is considered to be a growing indicator in the impact and clinical outcomes of patients with COVID-19. Screening with coagulation panels, including d-dimer, prothrombin time, platelet counts, and fibrinogen, is considered to be essential to identifying patients with severe COVID-19 risk and potential negative outcomes. Several international organizations are leading the charge in identifying and publishing recommendations and guidances for coagulopathy management in COVID-19 patients. Organizations endorsing increasing monitoring for patients with thrombotic diseases and implementing early interventions include:

• American College of Cardiology
• British Society of Hematology
• European Society of Vascular Medicine
• International Society of Thrombosis and Haemostasis
• North American Thrombosis Forum

FOR MORE INFORMATION:

Kalorama Information’s Hematology Markets