VT-111 results

Viron phase 2a data, published in leading cardiovascular journal, circulation: cardiovascular interventions. VT-111 results demonstrate statistically significant reduction in two key biomarkers of cardiac damage.

 LONDON, ON, Dec. 16 /PRNewswire/ - Viron Therapeutics Inc. today announced that the results of Viron's Phase 2a trial for VT-111 were published today in Circulation: Cardiovascular Interventions. In the study led by Dr. Jean-Claude Tardif, Director of the Research Centre at the Montreal Heart Institute, VT-111, also known as Serp-1, met both its primary and secondary endpoints of safety and biological activity in Acute Coronary Syndrome (ACS) patients receiving coronary stents. VT-111 is a protein produced by the myxoma virus that allows the virus to lower its host's inflammatory response to infection.

"Although the use of cardiovascular stents have dramatically improved the outcomes for patients with occlusive coronary artery disease, numerous studies have shown that the procedure itself can cause what is termed peri-procedural myocardial injury (PMI)," said James Rae, CEO of Viron. "A recent review in the European Heart Journal shows that 30% of patients receiving coronary stents sustain an injury to the heart tissue arising from the procedure itself and the biomarkers most useful in measuring this cardiac injury are CK-MB and Troponin I. Viron's Phase 2a trial showed a statistically significant, dose-dependent reduction in these two key biomarkers of cardiac damage, at multiple timepoints, with a particularly potent effect in the first 24 hours after the placement of the stent. If the incidence of PMI was reduced, clinical outcomes would improve for many of the almost 3 million patients each year that receive cardiac stents in North America and Europe."

Numerous studies have shown that a rise in CK-MB and Troponin I in the first 24 to 48 hours after placement of a stent is evidence that the procedure has caused damage to the heart tissue, putting these patients at a much higher risk of negative clinical outcomes. A therapy to reduce PMI would need to impact these biomarkers in that critical first 24 hours.

VT-111 also showed a strong trend towards reducing Major Adverse Cardiac Events (MACE; a clinical endpoint comprised of myocardial infarction, revascularization, coronary artery bypass graft (CABG) or death) in the higher dose group, with no MACE events at the six month follow-up, compared to the placebo group, which had 17% MACE rate.

"Reductions in these cardiac enzymes are very encouraging given the strong correlation between a rise early after the procedure and the probability that those patients will experience a subsequent clinical event," said Dr. Carl Pepine, past president of the American College of Cardiology. "These data are even more encouraging when you note that the high dose group saw no MACE compared to the 17% MACE rate seen in the placebo arm of the study. I am very interested to see a larger study of VT-111 in this patient population. It may also be possible for VT-111 to have an even greater impact if delivered in doses above the top dose of 15 micrograms per kilogram (µg/kg) tested in this trial."

Starting immediately before stent placement in this double-blind, placebo-controlled Phase 2a trial, 48 patients received intravenous doses of placebo or VT-111 once daily for three days. Subjects were then followed for six months for evaluation of safety and a variety of inflammatory and cardiac enzyme biomarkers.

Viron plans to continue further clinical testing in 2011 with a fully glycosylated version of the original drug that has shown significantly enhanced efficacy in animal models over the original drug with a similarly high margin of safety.

The article entitled "A Randomized, Controlled, Phase 2 Trial of the Viral Serpin Serp-1 in Patients With Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention," appears in the December 2010 Issue of Circulation: Cardiovascular Interventions.

 

Dick Cheney and modern heart failure treatment

Former Vice President Dick Cheney was released from the hospital on April 3rd, 2012, 10 days after getting a heart transplant. Cheney waited nearly two years for the transplant. During his life he sustained five heart attacks, the first at age 37 and the most recent one in 2010.

Stenting for stable coronary artery disease is wrong!

In  a January 4th JAMA editorial, the authors describe that patients were not being helped by a variety of well-established procedures including stenting for stable coronary artery disease:

Medical therapy often superior than stenting

There is more and more evidence of the superiority of medical therapy over stenting, not only with coronary artery disease, but also with stenotic arteries in your brain: The 30-day rate of stroke or death associated with stenting (14.7%) is nearly 2.5 times as high as the 6% rate associated with stenting in high-risk patients with a 70 - 90 % severe intracranial arterial stenosis.

Left-main PCI is only appropriate for a minority of patients

An atricle published in Cardiovascular Business on November 8, 2011 is very much in-line with our previous publications on this website about optimal treatment of Coronary Artery Disease that includes a Left Main Stenosis and/or three vessel disease:

Weight gains after dieting

As is well known, although restriction of diet often results in initial weight loss, more than 80 per cent of obese dieters fail to maintain their reduced weight.

A new study from Australia involved 50 overweight or obese patients without diabetes in a 10-week weight-loss program using a very-low-energy diet. Levels of appetite-regulating hormones were measured at baseline, at the end of the program and one year after initial weight loss.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Graft Surgery in Left Main Coronary Artery Disease

In this study, the authors analyzed the combined results of four different randomized clinical trials, comparing PCI with CABG in the treatment of Left Main CAD.

Comparing MACCE (major adverse cardiac or cerebrovascular events) they found “nonsignificantly different 1-year rates of MACCE” between the two treatment modalities after 12 months (14.5% vs. 11.8%, P value 0.11).

The studies included were:

Many patients with coronary artery disease are not treated optimally

As we have reported repeatedly in previews of the SYNTAX trial, the rate of CABG surgeries declined by approximately one-third and that of PCI procedures fell by 4% between 2001 and 2008, according to another study published in JAMA in May, 2011.

The ABCS of Preventing Heart Attacks and Strokes

Each year, more than 2 million Americans have a heart attack or stroke, of whom more than 800,000 of them die; cardiovascular disease is the leading cause of death in the United States and the largest cause of lower life expectancy among blacks.

Diastolic Dysfunction and Risk of Heart Failure

Left ventricular diastolic dysfunction is highly prevalent, tends to worsen over time, and is associated with advancing age. Worsening diastolic function can be detected even in apparently healthy persons, the conclusion by the authors of a recent article published in JAMA.

Statin usage in low-risk patients

Cardiovascular disease (CVD) is ranked as the number one cause of mortality and is a major cause of morbidity world-wide. Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of coronary heart disease (CHD) is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with coronary artery disease. The case for primary prevention, however, is less clear.

Trans catheter aortic valve implantation (TAVI)

There are many patients with severe aortic stenosis and coexisting conditions who are not candidates for surgical replacement of the aortic valve. For those patients trans-catheter aortic-valve implantation (TAVI) may be an option.

Treatment of Ischemic Heart Failure

Patients with heart failure caused by blocked coronary arteries, who are treated with bypass surgery  reduce their risk of dying from heart disease, and also the risk of death from any cause or hospitalization from heart disease, compared with medication alone.

Cardiac Surgery Risk Analysis

Since its first publication, our cardiac surgery risk calculator has proven very popular, with over 1000 completed questionnaires since August, 2010. Although the validity of the analysis is somewhat questionable, it has nonetheless shown some interesting results and showcases how this type of data can be utilized, especially if coupled with outcome analysis.

SYNTAX and CABG after two years

A new study, published in the Januari, 2011 issue of the Journal of Thoracic and Cardiovascular Surgery, reviewed 2-year follow-up outcome data of  1468 CABG patients from the SYNTAX trial.

Low HDL and Cardiovascular Risk

Current national guidelines for CVD risk reduction are primarily focused on strategies to reduce levels of low-density lipoprotein cholesterol (LDL-C), with the most recent focus being on “lower is better” rather than an effort to increase high-density lipoprotein cholesterol (HDL-C). A careful examination of randomized, controlled trials (RCTs) using statins demonstrates that even with intensive statin therapy and intensive LDL-C lowering, many cardiovascular events are not prevented.

VT-111 results

Viron phase 2a data, published in leading cardiovascular journal, circulation: cardiovascular interventions. VT-111 results demonstrate statistically significant reduction in two key biomarkers of cardiac damage.

Improper Cardiac Stent Implantations

Senate Finance Committee Chairman Max Baucus (D-Mont.) and Ranking Member Chuck Grassley (R-Iowa) today released a Finance Committee report detailing the case of a doctor who reportedly implanted nearly 600 potentially medically unnecessary stents from 2007 through mid-2009 at St. Joseph Medical Center in Towson, Maryland, and his relationship with the manufacturer of the stents, Abbott Labs.  The Senators’ report found that the questionable stent implantations cost the Medicare program $3.8 million during that period.

Small vessels are a predictor of restenosis after percutaneous coronary intervention (PCI)

In an article[1] published on October 9,2010 in Vascular Health and Risk Management, a British journal, the outcome of PCI in small coronary arteries was studied. Small coronary arteries (with a diameter of <3 mm) account for about 40%–50% of all coronary stenoses.

Is HbA1c the gold standard for diagnosis of Diabetes?

HbA1c is not a sure-fire tool for Diabetes diagnosis.

SYNTAX three year results

The latest SYNTAX results extend CABG's superiority over PCI.

PCI for STEMI should be limited to infarct related coronary arteries

NEW YORK (From Reuters Health) - Performing percutaneous coronary interventions (PCI) in non-infarct-related coronary vessels along with primary PCI for ST-segment elevation myocardial infarction (STEMI) appears to jeopardize patient survival, Canadian researchers reported online June 8 in the European Heart Journal.

Treatment of Chronic Kidney Disease (CKD) and multivessel CAD

CABG is associated with better survival than PCI with DES in patients with non Hemodialysis Dependent (HD) Chronic Kidney Disease (CKD) and multivessel CAD, but CABG patients have a greater short-term risk of needing permanent  hemodialysis.

Patients with 3-vessel disease should be operated!

Point-Counter point 1

Best way to revascularize patients with main stem and three-vessel lesions. Patients should be operated!

Patients with three vessel disease should undergo PCI!

Point-Counter point 2

Best way to revascularize patients with main stem and three-vessel lesions: Patients should undergo PCI![i]

Computed Tomography Coronary Angiography (CTCA) screening for Coronary Artery Disease

The major risk factors of inappropriate diet, physical inactivity, high cholestreol (> 250 mg%), high BMI (>26) and hypertension (>155 mmHg) and smoking, explain at least 75% of new cases of Coronary Artery Disease (CAD). In the absence of these risk factors, CAD is a rare cause of death.

Courage Under Fire - On the Management of Stable Coronary Disease

George A. Diamond, and Sanjay Kaul, J. Am. Coll. Cardiol. 2007;50;1604-1609

While the actual numbers are open to debate, the simple fact is that many patients with stable angina (and an additional number of asymptomatic patients) are undergoing PCI without having received sufficient medical therapy.

 

 

The Syntax Trial

Although coronary-artery bypass grafting (CABG) has been the standard of care for patients with left-main or three-vessel coronary disease who require revascularization, percutaneous coronary intervention (PCI) with stenting is also an option in such cases. These two interventions were compared in the SYNTAX trial, which was sponsored by the manufacturer of the Taxus drug-eluting stent.

Occluded Artery Trial

The Coronary Intervention for Persistent Occlusion after Myocardial Infarction (Occluded Artery Trial, (OAT) study evaluated treatment of 2166 high-risk, but otherwise stable survivors of a myocardial infarction and persistent total occlusion of the infarct-related coronary artery.

High risk criteria included an ejection fraction of <50% or proximal occlusion (TIMI flow =0-1). Treatment was randomized to either routine PCI or stenting with Optimal Medical Therapy (OMT) (1082 patients), or OMT alone (1084).

For Profit Research

“For Profit Research” with investigators receiving consulting fees from the sponsor (not much progress since 2001):

Medical Journal Editors Demand Accountability from Study Authors, Sponsors, AJHP, 11/1/2001: "clinical studies are increasingly conducted with the goal of marketing products ”

 

Niacin vs. Ezitimibe, Niacin Therapy

Extended-Release Niacin or Ezetimibe and Carotid Intima–Media Thickness (The ARBITER 6–HALTS trial, Taylor et al., NEJM, 11/15/2009): In a recent study, the effect of  extended-release niacin (Niaspan, target dose, 2000 mg per day) was compared with ezetimibe (Zetia, 10 mg per day) in a small group of 208 patients with established Coronary Artery Disease (CAD). All these patients had been on long-term Statin therapy.

CABG – Stroke and Surgery

Combining Cardiac Surgery and surgery for carotid stenosis is not effective in the prevention of Stroke.

Elective cardiac catherization

Low Diagnostic Yield of Elective Coronary Angiography (From: Manesh R. Patel, M.D.,et al.,N Engl J Med 362;10, 886-895)

PCI equals OMT

Improved medical therapy equals Percutaneous Coronary Intervention (PCI) for angina relief in patients with stable Coronary Artery Disease.

APEX-AMI trial Analysis

Although 40-65% of patients admitted for treatment of an acute heart attack with percutaneous coronary intervention (PCI) have multiple blockages, current guidelines strongly suggest to limit the procedure to the blocked artery (the culprit vessel).

PCI in “Non-culprit coronary arteries” is associated with a significantly increased risk of dying, as Armstrong and colleagues of the APEX-AMI trial recently published in the European Heart Journal of June, 2010.

CAS vs CEA (the CREST study)

“Primary composite outcomes” (lumping complications together into one composite complication), allows shading of negative results that only become visible with careful study of a publication. In the CREST study described below, the authors combined procedural death, stroke and myocardial infarction together into a composite complication. In doing so they found no outcome difference between Carotid artery stenting (CAS) and Endarterectomy (CEA).

I strongly disagree with the conclusion as well as this kind of data manipulation, and will address the issue in my analysis of this paper:

Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST)[1], a new study published in the latest issue of the NEJM, examined treatment outcomes for Carotid Artery Disease, a major cause of stroke. Stroke is the third most common cause of death among adults and the leading cause of long-term disability. CREST compared Carotid Artery Stenting (CAS) with Carotid Artery Stenting (CAS) as treatment of severe Carotid Artery Disease.

CAS was associated with more than double the mortality rate of CEA (Hazard Ratio (HR): 2.25) and an almost triple rate of ipsilateral stroke (HR: 2.67). The incidence of Myocardial Infarction (MI) in CSA patients occurred at half the rate of CEA treated patients.

    Carotid Artery Stenting (CAS) (N=1262) Carotid Artery Endarterectomy (CEA) (N=1240) Hazard Ratio (HR) CAS vs. CEA P-Value
Death   9   4   2.25 0.18
Complications              
  CVA Any Major Ipsilateral Any Major Ipsilateral    
    52   29   1.79 0.01
      11   4 2.67 0.09
  MI 14   28   0.5 0.03
Total Complications 66 57   1.18 0.38  

The results did not change substantially during the 4-yr follow-up period:

    Carotid Artery Stenting (CAS) (N=1262) Carotid Artery Endarterectomy (CEA) (N=1240) Hazard Ratio (HR) CAS vs. CEA P-Value
Death   94   83   1.12 0.45
Complications              
  CVA Any Major Ipsilateral Any Major Ipsilateral    
    105   75   1.4 0.03
      16   6 2.56 0.05
  MI NA   NA   NA NA
Total Complications 105   75   1.11 0.51

However, despite this the authors concluded that  “… CREST results indicate that carotid-artery stenting and carotid endarterectomy were associated with similar rates of the primary composite outcome — periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke — among men and women with either symptomatic or asymptomatic carotid stenosis. However, the incidence of periprocedural stroke was lower in the endarterectomy group than in the stenting group, whereas the incidence of periprocedural myocardial infarction was lower in the stenting group, … with younger patients having a slightly better outcome with carotid artery stenting and older patients having a better outcome with carotid endarterectomy…”

The study was supported by Abbott Vascular Solutions (formerly Guidant), including donations of Accunet and Acculink systems (the stents used), equivalent to approximately 15% of the total study costs.

An editorial[2] accompanying this article contradicted the CREST conclusions: … “the results are broadly consistent with those in previous trials. Namely, carotid-artery stenting is associated with a higher periprocedural risk of stroke or death, a difference that was still significant at 4 years. A recent meta-analysis of 11 randomized trials performed through 2009 (not including CREST) showed that carotid endarterectomy was superior to carotid-artery stenting, … We conclude that until more data are available, carotid endarterectomy remains the preferred treatment for most patients with symptomatic carotid stenosis”...

Remarks

I agree for the most part with the editorial but would the additional comments:

Treatment of Carotid disease has as goal the prevention of stroke through restoration of blood flow.

  • Major Ipsilateral stroke often translates into a permanent disability such as hemiparesis. Prevention of this complication is the one and only goal of any carotid intervention.
  • Peri-operative MI is a rare event, rarely of clinical consequence, and largely preventable in the hands of an experienced surgical and anesthesia team.
  • The CREST analysis suggests that Death, Stroke and peri-procedural MI are equal complications, an absurd conclusion.
  • Even though the more than double CSA mortality rate did not reach statistical significance in this study, it has in a number of other publications.

The Appendix listed together with the CREST publication shows the following[3]:

Somehow this page did not make it to the article. Why? Is it because the authors thought this to be meaningless information, or is it because the results are contradictory to the wished-for corporate sponsored outcomes?

As a surgeon with lots of “carotids” under my belt, one of my problems was to decide what to do first, CABG or CEA, since most of my patients had CAD as well as Carotid disease. Modern surgical techniques are so good that peri-operative stroke was not an issue: I cannot remember a single stroke in my patients (nor any mortality). As a procedure, it took about 45 minutes (“skin-to-skin”) to do the operation, discharging the patient 12-24 hours later. I doubt a stent placement can be done any quicker, and it certainly costs a lot more than two sutures and the occasional patch (the cost of OR and Lab estimated as equivocal).

So what do you prefer, an expensive stent with more than double the mortality and an almost triple stroke rate, in addition to which patients now need to be managed on a regimen of anti-platelet drugs with all the associated  risks (thrombosis etc.)?

And what about another industry sponsored study only confirming what so many other investigations have found, i.e. that CEA is a superior treatment option for carotid artery disease? Or the authors’ conclusions, contradicting their own results?

DR T


[1] Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis, Thomas G. Brott, M.D.et al, (N Engl J Med 363:11-23)

[2] Carotid-Artery Stenting in Stroke Prevention, Stephen M. Davis, M.D., and Geoffrey A. Donnan, M.D., (N Engl J Med 36: 80-82)

[3] Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis. N Engl J Med 2010;363:11-23 Supplementary Appendix, Brott TG et al. (N Engl J Med 363:11-23)

Statins may improve your cholesterol but not your cardiac risks

Question: 

Do Statins really improve the risk of coronary artery disease?

A paper published in this issue of the Annals of Internal Medicine, reviewed the association of statin therapy and cardiovascular outcomes, but found little difference between treated and untreated patients. As the current focus of statin therapy is to reduce low-density lipoprotein cholesterol (LDL-C), rather than increase high-density lipoprotein cholesterol (HDL-C), the conclusion was that persistent low levels of HDL-C may be responsible for ongoing risks of cardiovascular events such as myocardial infarction (MI) and cardiac death.

The ARBITER 6 trial that compared Niacin with Ezitimibe came to the same conclusion in 2009.

Treatment of 3VD with/without Diabetes in Washington State

A paper from Washington State examines the treatment of patients with multi-vessel coronary artery disease. A second paper, like the BARI-2D study and a much earlier published paper, focuses on patients with diabetes and 3VD. The short as well as long term benefits of CABG for these type of patients have been described in the SYNTAX trial as well as other publications but have rejected in daily clinical practice with a call for new studies as the most positive answer.

An approach to Hypertension Treatment In The Elderly

Question: 

Is there a diffence in the treatment of hypertension in the elderly?

In clinic today, I saw an 85 year old woman with Parkinson’s disease for follow-up of her high blood pressure. Her pressures have been difficult to control.

Today her BP is 170/80 with a heart rate of 62 bpm. She is taking an ACEi and a beta-blocker. Her daughter supervises the administration of her medications. She has no known history of heart disease or stroke, and mild renal disease which has been stable. Her EKG shows left ventricular hypertrophy.