Health Conditions

What is on the horizon?

Thrombolytic agents are injected slowly into the bloodstream to dissolve dangerous clots rapidly. They are usually reserved for life-threatening pulmonary embolism (blood clot in the lung) since, they have a greater risk of causing serious bleeding. They are given under close supervision in hospitals. However, studies are now investigating the effectiveness and safety of these agents when they are injected directly into blood clots.

An oral direct thrombin inhibitor, dabigatran, is currently being investigated in Stage III clinical trials and has been found to be as effective as enoxaparin for prevention of DVT when taken for one month after total hip replacement surgery. Although the researchers in this study did not find a difference in major bleeding (a common side effect of these medications) between the dabigatran and enoxaparin groups, larger studies will be done in the future to further assess this risk. The only other oral anticoagulant available today is warfarin, which requires extensive monitoring through regular blood tests. Dabigatran has not yet been approved by the FDA, but if future studies continue to find positive results it could become a very important drug in the prevention and possibly treatment of DVTs.

Therapies such as low molecular weight heparin used to prevent DVTs have also gained the interest of many healthcare providers. It is believed that measures used to prevent a DVT after neurosurgery may have a significant effect on decreasing the rate of death after surgery. More clinical studies are needed at this point to determine the use of preventative treatments.

Idraparinux (a Factor Xa Inhibitor) is a new pentassacharide that has been found in one study to have similar efficacy as standard therapy (heparin or low molecular weight heparin plus warfarin) in treating DVT, but was less efficacious in patients with pulmonary embolism (PE). Idraparinux is similar to fondaparinux but lasts much longer in the body, which allows it to be given as a weekly injection instead of daily or twice daily. But the fact that it did not show effectiveness against PE may limit its use because the other injectable anticoagulants have similar efficacy for both DVT and PE.

Rivaroxaban (a Factor Xa Inhibitor) is also currently being studied for prevention and treatment of DVT. It is another oral anticoagulant and is in the beginning of Phase III clinical trials, mainly being studied for prevention of DVT after total knee and hip replacement surgeries. Neither of these drugs has been approved by the FDA yet. However, if they are found to be effective in the clinical trials, they may gain FDA approval in the next few years.