Sunday, June 21, 2015

A little more on PCSK9 inhibitors

The author of the following open letter to Medscape (I think you have to register to read, so I've copy/pasted it to make access easy), a Dr Mandrola, is not a THINCS member that I'm aware of. Not a Dr Ravenskov or Dr Kendrick.

He appears to be a mainstream cardiologist who is aware of how essentially all lipid lowering trials have bombed and that statins, whatever small benefit they show in drug company funded secondary prevention trials, probably don't work by LDLc lowering.

He is urging caution on PCSK9s. This is good. Never mind the known cognitive decline. My guess he is worrying (but not talking) about what the cancer death rate will have risen to by five or six years down the road. He has read J-LIT.

I know this is not unprecedented. It just feels like it. There really are medics in the cardiological wall who do think and who possibly care. That's nice to see.

Peter

Here is the letter:


www.medscape.com June 16, 2015

Dear FDA: Resist the Urge on PCSK9 Drugs

Last week, an FDA advisory committee recommended approval of two proprotein convertase subtilisin kexin 9 (PCSK9)–inhibitor drugs. A formal decision is expected later this summer. The FDA usually follows the advice of its advisory committees, but not always.

This is a big moment in cardiology. It is also a huge gamble for the FDA.

I believe the FDA should break with its advisory committee and say no.

Not yet. It's too early to unleash these drugs on American patients and doctors.

Here are four reasons.

Target Confusion

The first reason the FDA should say no (not yet) is the target. PCSK9 drugs lower LDL cholesterol. That fact is clear. But our target is not a lab value; it's heart disease.

Any doctor who sees patients knows heart disease comes from many things. These factors, which affect individuals in genetically varied ways, accumulate over years, not months. LDL-C may be important, or very important, but it is just one risk factor. Even in patients with familial hypercholesterolemia, LDL-C may be one of many risk factors.

The stunning LDL-C lowering from PCSK9 drugs might prevent future heart attacks, strokes, and deaths. The key word in that sentence is might. We don't know. The biology of these drugs is beautiful, but that beauty should not obscure the current state of knowledge.

What we know now is that PCSK9 drugs are effective at LDL-C lowering. That is it. The OSLER[1] and ODYSSEY[2] trials were not powered to look at outcomes. Those data are forthcoming in the FOURIER trial, which has completed enrollment of 27,000 subjects, and results are expected in 2017. Why not wait?

Do No Harm

The second reason the FDA should hold off is the risk. The mission statement of the FDA says its charge is to "protect the public health by [ensuring] the safety, efficacy, and security of human and veterinary drugs, biological products, medical devices, our nation's food supply, cosmetics, and products that emit radiation."

What I read into that is harm avoidance. In this way, I see the FDA's role as similar to a physician's. Yes, we want to benefit our patients, but the guiding principle must be to avoid harm. This is especially critical when treating people for something (an MI, stroke, or death) that has yet to happen. Having a high risk for a disease is not the same as having a disease.

It is true; in both the OSLER and ODYSSEY studies, evolocumab (Repatha, Amgen) and alirocumab (Praluent, Sanofi/Regeneron) looked reasonably safe. But follow-up was only 11 months in OSLER and 78 weeks in ODYSSEY. That's too short. Heart-disease prevention is not a 2-year endeavor.

In both studies, more patients on the PCSK9 inhibitor reported neurocognitive effects. That may be significant. Is it implausible to think cholesterol might be important for brain cells? Here, let's also be mindful of euphemism. "Neurocognitive function" is a fancy way to say "think." Thinking is what makes us human. So if we think of this issue from a patient-centered standpoint, how many humans would trade a dull mind for a possible benefit 2 to 10 years in the future?


The third reason the FDA should say no is historical. The use of surrogate markers for cardiac drugs has proven to be a bad gamble. We can point to niacin[3], fibrates[4] and cholesteryl ester transfer protein (CETP) inhibitors[5] as evidence of that failure. Although statin drugs are potent LDL-C lowering agents and proven effective in reducing cardiac events in high-risk patients, no one argues these drugs don't have important pleiotropic effects. The case of ezetimibe is hardly supportive of the LDL-C hypothesis. In the IMPROVE-IT[6] trial, the tiny absolute benefit of ezetimibe (composite end point) was achieved against simvastatin—a straw-man comparator if there ever was one.

Distractions—Benefits Missed

The fourth reason the drugs are not ready is the potentially harmful effects of distraction and benefits missed. Many have argued, including patients with familial hypercholesterolemia, that PCSK9 drugs should be approved now because of the benefits missed while waiting for the FOURIER data. Of course, this assumes positive results are forthcoming.

Another way to look at benefits missed is to imagine the devastating impact of all that will not occur if these expensive drugs are approved. If we spend billions of dollars on these drugs—and make no mistake, if the FDA approves them, we will spend billions, then that takes money (and attention) away from many other facets of heart disease prevention.

Look at the case of ezetimibe, the last drug approved without outcomes data. Billions were spent on a drug with minimal to no effect on outcomes. What were the benefits missed of those billions? Healthcare budgets are limited. If we spend money on unproven drugs, we aren't spending it on cardiac rehab programs, parks, bike lanes, school nutrition programs, and many other useful heart-healthy public-health projects.

2017 is just around the corner. I say the FDA should resist the urge. Protect the public. Do no harm.

JMM

References

1. Sabatine MS, Giugliano RP, Wiviott SD, et al. Efficacy and safety of evolocumab in reducing lipids and cardiovascular events. N Engl J Med 2015; 372:1500-1509. Article
2. Robinson JG, Farnier M, Krempf M, et al. Efficacy and safety of alirocumab in reducing lipids and
cardiovascular events. N Engl J Med 2015; 372:1489-1499. Article
3. The AIM-HIGH Investigators. Niacin in patients with low HDL cholesterol levels receiving intensive statin therapy. N Engl J Med 2011; 365:2255-2267. Article
4. Ginsberg HN, Elam MB, Lovato LC, et al. Effects of combination lipid therapy in type 2 diabetes mellitus. N Engl J Med 2010; 362:1563-1574. Article
5. Nissen SE, Tardif JC, Nicholls SJ, et al. Effect of torcetrapib on the progression of coronary atherosclerosis. N Engl J Med 2007; 356:1304-1316. Article
6. Cannon CP, Blazing MA, Giugliano RP, et al. Ezetimibe added to statin therapy after acute coronary syndromes. N Engl J Med 2015; DOI:10.1056/NEJMoa1410489. Article © 2015 WebMD, LLC

8 comments:

Spittin'chips said...

I think this may be the same fella here - http://www.drjohnm.org/heart-disease-by-drjohnm/

Apart from heavy focus on exercise (cycling), it's not clear what he considers to be 'healthy living' and unfortunately he uses the 'good' and 'bad' cholesterol terminology.

What I'd like to know is how people like this appear to have a 36 hour day.

Peter said...

So even a cardiological drongo can see that lipid lowering to the levels now possible might just be a Bad Thing! Cool.

Peter

Bill said...

At the recent ADA conference in Boston, they mentioned that new recommendations for prescribing statins should be based on the presence of risk factors, not cholesterol levels... and LDL targets should no longer be considered.

Peter said...

Yes, Bill, it expands the market. What I like about this minion is that he is worried about low TC per se..... As he should be, of course.

Peter

Specious Sine said...

I came across this article http://www.hindawi.com/journals/mi/2010/535612/
It's about "dyslipidemia" aka hypercholesteremia and psoriasis, noting a hypothesis by Lacroix that as significant cholesterol is located in psoriatic plaques, as well as serum, psoriasis is in effect "a form of cholesterol elimination from the skin"(!)

Yes statins have been flagged, with unaccountably adverse, and subsequently no better than placebo results. Even so several years later, in 2013 there is an optimism and belief in the fit of the mechanisms to the disease and contradictions are dismissed thus:

"To date several cases have been reported in which atorvastatin or pravastatin worsened psoriasis. Based on these results, it seems that statins represent a promising class of medications which could be extensively used in psoriasis."
http://link.springer.com/article/10.1007%2Fs00403-013-1374-1

Peter said...

Good grief. I wonder if English was the first language of the authors, or the reviewers. Doesn't seem to make sense!

Peter

karl said...

I came to the same opinion - and refused to be part of the trial. (see comment in previous blog)

One last bit - I would like to see a study that shows any risk factor from LDL if oxLDL levels are controlled for. I don't think any such study exists. And one important factor that reduces oxLDL - is keeping blood sugar at healthy low levels.

George Henderson said...

Well looky here - PCSK9 is protective against metabolic harms from high ApoB concentrations!

http://www.lipidjournal.com/article/S1933-2874(15)00294-9/abstract

Not only that, but it HELPS with LDL clearance in that paper. WTF? They seem to be basing PCSK9 inhibitors on cardioprotection in PSCK9 knockout phenotype. That's a big assumption - knockout of genes has huge pleiotropic effects, inhibiting their products can have completely different effects.