Cardiovascular disease is the leading cause of death in the United States. A common cause of cardiovascular disease is atherosclerosis, or premature plaque buildup, which occurs when cholesterol and inflammatory cells accumulate in blood vessels. Researchers have shown a strong correlation between high cholesterol levels and subsequent cardiovascular diseases. As such, lowering cholesterol is a key component in preventing and managing cardiovascular disease.
Cardiovascular disease is an area of focus for us. We have created a cardiovascular disease franchise comprised of drugs that target all the key components of cardiovascular disease, including various atherogenic lipids, inflammation and thrombosis, an aberrant blood clot formation responsible for most heart attacks and strokes. For example, we are developing a drug that lowers apoC-III and triglycerides, which are both independent risk factors for cardiovascular disease. Our most recent addition to our cardiovascular franchise is our drug that lowers Lp(a), another independent risk factor for cardiovascular disease. Currently available lipid-lowering therapies do not significantly lower apoC-III, triglycerides, or Lp(a). We believe that targeting apoC-III and Lp(a) could provide a complementary approach to lipid-lowering therapies, including KYNAMRO. We are also developing a drug that lowers C-reactive protein, or CRP, a protein that scientists associate with cardiovascular disease. And finally, our cardiovascular franchise includes two anti-thrombotic agents, which could offer safer, more effective alternatives to anti-clotting agents currently on the market.
We believe antisense drugs could have a significant positive effect in patients with high cardiovascular risk. Because there are many liver-produced targets that affect the production of cholesterol particles, clotting factors and other factors that contribute to the inflammatory components of cardiovascular disease, the liver is an ideal target organ for cardiovascular disease therapies, and antisense drugs in particular. Our antisense drugs distribute to the liver and inhibit the production of many targets associated with cardiovascular risk, creating an opportunity for us to develop many complementary and effective antisense drugs for cardiovascular disease.
KYNAMRO™ (mipomersen sodium) is an oligonucleotide inhibitor of apolipoprotein B-100 synthesis indicated as an adjunct to lipid-lowering medications and diet to reduce low density lipoprotein-cholesterol (LDL-C), apolipoprotein B (apo B), total cholesterol (TC), and non-high density lipoprotein-cholesterol (non-HDL-C) in patients with homozygous familial hypercholesterolemia (HoFH).
ISIS-APOCIIIRx is an antisense drug we designed to reduce apolipoprotein C-III, or apoC-III, protein production and lower triglycerides. ApoC-III regulates triglyceride metabolism in the blood and is an independent cardiovascular risk factor. People who do not produce apoC-III have lower levels of triglycerides and lower instances of cardiovascular disease. ApoC-III is elevated in patients with dyslipidemia, or an abnormal concentration of lipids in the blood, and is frequently associated with multiple metabolic abnormalities, such as insulin resistance and/or metabolic syndrome. In human population studies, lower levels of apoC-III and triglycerides correlated with a lower rate of cardiovascular events. In certain populations, apoC-III mediates insulin resistance, which can make metabolic syndrome worse.
In preclinical studies, ISIS-APOCIIIRx diminished symptoms of metabolic syndrome and reduced atherosclerosis in mice. We have completed a Phase 1 study evaluating the safety and activity of ISIS-APOCIIIRx in healthy volunteers. In this study, ISIS-APOCIIIRx produced rapid, dose-dependent median reductions of up to 78 percent in apoC-III protein and up to 44 percent in blood triglycerides. All subjects tolerated ISIS-APOCIIIRx well.
We are pursuing a staged development plan for ISIS-APOCIIIRx designed to shorten the time to bring this drug to patients at high-risk of cardiovascular disease and pancreatitis. These are the patients with the highest unmet medical need who have severely high triglyceride levels despite currently available therapies and are at the greatest risk. Patients with triglycerides greater than 880 mg/dL are at a higher risk of developing pancreatitis, a painful and sometimes fatal disease that requires hospitalization and close monitoring. In these patients who cannot reduce their triglycerides to acceptable levels, the primary therapy is diet, which requires strict adherence and is often unsuccessful.
Our plan is to initially develop ISIS-APOCIIIRx to treat patients with triglyceride levels greater than 880 mg/dL and as we gain additional experience in these patients, expand to include other less severe patient populations. We are evaluating ISIS-APOCIIIRx in a Phase 2 study in patients with very high triglyceride levels of greater than 500 mg/dL. In this study, we plan to enroll approximately 100 patients who have triglyceride levels of 500 mg/dL or higher, and evaluate ISIS-APOCIIIRx as a monotherapy and in combination with fibrates. We are also evaluating ISIS-APOCIIIRx in patients with type 2 diabetes and high triglyceride levels.
ISIS-CRPRx is an antisense drug that targets CRP, a protein produced in the liver. CRP levels increase dramatically during inflammatory disorders, and scientists have linked excessive amounts of CRP to coronary artery disease. Furthermore, a growing body of evidence from clinical trials implicates CRP in cardiovascular disease progression. These results suggest that it may be therapeutically beneficial to significantly decrease CRP levels in patients who are at risk for coronary events. In addition, clinicians have associated elevated CRP levels with a worsening of overall outcomes in conditions such as end-stage renal disease and multiple myeloma, suggesting that lowering CRP could help these patients. CRP elevation is also evident in many other major inflammatory diseases such as Crohn's disease and rheumatoid arthritis.
In preclinical studies, we observed that our antisense inhibitor of CRP suppressed liver and serum CRP levels. We evaluated ISIS-CRPRx in a Phase 1 study in which ISIS-CRP Rx produced statistically significant reductions in CRP in the cohort of subjects that entered the study with elevated levels of CRP. All subjects tolerated ISIS-CRPRx well. Our Phase 2 plan for ISIS-CRPRx is to evaluate the drug in diseases with elevated CRP that could provide early proof-of-concept.
We completed a second Phase 1 study designed to evaluate if pretreatment with ISIS-CRPRx can blunt an acute severe increase in CRP. In this study, healthy volunteers were treated with ISIS-CRPRx and then subjected to an endotoxin challenge, which causes an increase in CRP and other inflammatory markers. In addition, we are evaluating ISIS-CRPRx in a Phase 2 study in patients with rheumatoid arthritis in which we will evaluate the effect of lowering CRP in patients with chronically elevated levels. We are also evaluating ISIS-CRPRx in a Phase 2 study in patients with atrial fibrillation, or AF. AF involves an irregular heart rate that commonly causes poor blood flow to the body. In this study, we will evaluate the effect of lowering CRP on the frequency and duration of AF.
ISIS-FXIRx is an antisense drug we designed to treat clotting disorders. It targets Factor XI, a clotting factor produced in the liver that is an important component of the coagulation pathway. High levels of Factor XI increase the risk of thrombosis, a process involving aberrant blood clot formation responsible for most heart attacks and strokes. Elevated levels of Factor XI also increase the risk of venous thrombosis, a common problem after surgery, particularly major orthopedic procedures, such as knee or hip replacement. People who are deficient in Factor XI have a lower incidence of thromboembolic events with minimal increase in bleeding risk. Although currently available anticoagulants reduce the risk of thrombosis, physicians associate these anticoagulants with increased bleeding, which can be fatal.
In preclinical studies, ISIS-FXIRx demonstrated potent antithrombotic activity with no increase in bleeding compared with standard anti-clotting agents, including low molecular weight heparin, warfarin and Factor Xa inhibitors, all of which increase bleeding. We have completed a Phase 1 study evaluating the safety and activity of ISIS-FXIRx in healthy volunteers. In this study, ISIS-FXIRx produced dose-dependent statistically significant reductions of greater than 80 percent in Factor XI protein. In this study, subjects tolerated ISIS-FXIRx well with no increase in bleeding.
In 2012, we initiated a Phase 2 study evaluating ISIS-FXIRx in patients undergoing knee replacement surgery, also referred to as total knee arthroplasty, or TKA. This study is a comparator-controlled study, in which we will compare the safety and activity of ISIS-FXIRx to a commonly used anti-coagulant, enoxaparin. In this study, we are evaluating the effectiveness of ISIS-FXIRx in reducing the number of thrombotic events in patients following TKA without increasing bleeding. Given the mechanism of Factor XI inhibition, we believe that doctors could use our drug broadly as an anti-thrombotic in many different therapeutic settings for which additional safe and well tolerated anti-thrombotic drugs are needed.
ISIS-APOARx is an antisense drug we designed to reduce apolipoprotein(a) in the liver to offer a direct approach for reducing Lp(a), an independent risk factor for cardiovascular disease. Scientists associate high levels of Lp(a) with an increased risk of atherosclerosis, coronary heart disease, heart attack and stroke. Lp(a) levels in blood can vary greatly between individuals due primarily to genetic variations between individuals. As a result, Lp(a) levels are genetically determined, reached by the age of two and remain constant throughout the life of the individual. Diet and lifestyle changes have little impact on Lp(a) levels and currently therapies are not able to adequately reduce elevated levels of Lp(a) to acceptable levels in patients with elevated Lp(a). As a general guideline for ideal Lp(a) levels, the European Atherosclerosis Society recommends that Lp(a) levels be less than or equal to 50 mg/dL. Even patients who can control their LDL-C levels remain at high-risk of cardiovascular events if they have high levels of Lp(a). There is a significant need for a highly specific drug that can lower Lp(a). We plan to develop ISIS-APOARx to treat patients with high Lp(a) levels who are at severe risk of experiencing cardiovascular events. We are currently evaluating ISIS-APOARx in a Phase 1 study in healthy volunteers.
ISIS-FVIIRx is an antisense drug we designed to reduce Factor VII, a key component of the tissue factor coagulation pathway, for the treatment or prevention of thrombotic diseases. Clinicians have linked elevated levels of Factor VII activity with poor prognosis in several thrombotic diseases, such as heart attacks, and with cancer-associated thrombosis, which is the second leading cause of death in cancer patients.
In preclinical studies, antisense inhibition of Factor VII rapidly reduced Factor VII activity by more than 90 percent in three days, suggesting that physicians could use ISIS-FVIIRx in acute clinical settings, such as following surgery, to prevent patients from developing harmful blood clots. In addition, we observed no increase in bleeding with ISIS-FVIIRx, which is a common side effect of currently available anti-thrombotic drugs. ISIS-FVIIRx is the second drug to enter development as part of our strategy to create more potent and safer anti-thrombotic drugs that do not increase bleeding.