June 27, 2009

Questions about The Lantus/Cancer Association

UPDATE: August 17, 2009: A safety review of an ongoing study of Lantus,sponsored by Sanofi-Adventus, the drug company who produces Lantus, but where the drug company supposedly has no access to the findings, found no evidence that people taking Lantus in that study were seeing a higher rate of cancer.

Science Daily: Research Team Responds To Concerns About International Insulin Drug Trial

By now you've probably heard the disturbing news about the epidemiological studies that connected Lantus to a higher incidence of cancer.

It says something about our health system that this news was reported by the business press long before the health press noticed it. And the business press coverage was concerned entirely with the impact this news would have on share prices of Sanofi-Adventis-not on the health of the people taking the drug. That's how capitalism works, folks, and it is the reason for a lot of unnecessary drug-related morbidity. Companies will hide and suppress bad news about a drug as long as possible in the hopes of supporting their share price.

You can find the news and the actual full texts of the studies connecting Lantus and Cancer here:

Diabetologia - Cancer & Lantus

I don't have the time right now to do a detailed analysis of these four studies. But here are my initial thoughts. We know that high glucose levels promote the growth of cancers. We also know the demographic of who is prescribed Lantus: Type 2s who have been out of control for more than a decade. This is because most doctors are reluctant to prescribe insulin until patients have taken every oral drug available for years, even if their A1cs continue to climb. The typical A1c of a patient who starts Lantus is 10% and their fasting blood sugar is usually near 200 mg/dl.

NOTE (added 7/2): The editor of the "PRESENT DIABETES Newsletter" mailed 7/2/09, "If you look at the actual study data, you see that it's not real world: 2/3 of the patients were excluded, because they were on a combination regimen, e.g. basal-bolus insulin. Moreover, the glargine patients were on quite different regimens and used more oral medications. [Emphasis mine]"

When doctors put out-of-control Type 2s on "insulin" it tends to only be basal insulin. This is because most Type 2s get their diabetes care from family practitioners, instead of endocrinologists, and family doctors don't have the resources to provide the detailed education patients need to use fast acting insulin with meals effectively and without causing themselves hypos.

Dr. Tamler's note confirms my suspicions, the patients found to have higher rates of cancer were Type 2s on inferior basal-only regimens and high carb diets which ensure
the high blood sugars that promote cancer.

Basal insulins like Lantus cannot counter the blood sugar spikes caused by the high carbohydrate meals most doctors still recommend, meals filled with so-called "healthy whole grains" and bananas. So even when people with Type 2 inject huge doses of Lantus--100 units is a typical Type 2 dose--most long-term Type 2s "on insulin" still experience post-meal blood sugars that spike into the 200s. That is why the A1c of all too many Type 2s "on insulin" (i.e. Lantus) are almost always considerably higher than the ADA's anemic 7% target.

This means that these people, despite injecting Lantus regularly experience blood sugars are high enough to a) turn off their immune system allowing cancerous cells to begin to grow and b) feed those cancerous cells.

Besides that, patients "on Lantus" have been on cocktails of powerful oral drugs for years before starting Lantus. So one would want to know if some these patients who contracted cancer were taking Januvia, the single most promoted new diabetes drug for Type 2s. There is significant evidence that Januvia turns off a tumor suppressor gene. We also do not know the impact on cancer of the TZD drugs, Actos and Avandia.

So the valid study comparison that would tell us whether Lantus is in fact promotion cancer would be a comparison between two groups of people with Type 2 diabetes who have been matched for the length of time since their diabetes diagnosis, who have the identical A1cs and oral drug consumption histories, where the ONLY difference between the groups is whether or not they are taking Lantus.

If that comparison shows a higher incidence of cancer in the Lantus group, then Lantus is, in fact, a very dangerous drug.

But comparing Type 2s taking Lantus, Avandia, Actos, Metformin and Januvia with Type 1s using R insulin or for that matter, Type 2s taking only Sulfonylureas and NPH (a common European protocol), may mean that you are comparing two different populations with different blood sugar histories and drug exposures. If that is the case, the cancer incidence in the two groups may not stem from the Lantus, but from the other factors applying to the group prescribed Lantus.

This latest alarm, as scary as it is to people who have been taking Lantus, is probably GOOD news, because it will trigger some serious research into the cancer profile of all the analog insulins and perhaps, even, of the oral diabetic drugs.

If you have been using Lantus and are still running damagingly high blood sugars capable of suppressing your immune system--sugars higher than 140 mg/dl after meals--the first thing to do is drop those blood sugar levels. Give your body the help it needs to nip cancer in the bud. Each of us develops a few cancerous cells every year, but a healthy immune systems kills them off before they can proliferate. Remember that cancer cells require a lot of glucose to grow (and don't need to be insulin sensitive to use that glucose). If you are taking Januvia, stop. It has definitely been connected with a mechanism that promotes cancer in a way that is well-understood.

If Lantus does promote cancer independent of its inability to tightly control the blood sugars of people with Type 2 diabetes who eat high carb diets, it would be helpful to know what exactly it is about Lantus that promotes cancers so we could know if the other analog basal insulin, Levemir, and the fast acting analog insulins, Novolog, Humalog, and Apidra, also cause cancer.

NOTE (Added 7/2): Dr. Tamler also states this: "However, use of the insulin-sensitizing agent metformin has been associated with decreased cancer risk."

I think the doctors commenting on the Lantus news did have it right this time: we don't think we have the evidence yet to understand this disturbing finding. Whether we will get that evidence or be handed a bunch of spin and persiflage from the drug manufacturers designed to prop up their share price at the cost of human lives, is another question.



Meerkatdon said...

I'm a 51-year-old type 2 who was diagnosed at age 48 and immediately put on a Lantus/Novolog regimen. No oral medications before or after.

My daily dose of Lantus has crept up to 55 units. I carb-count and bolus with Novolg (jus like a type 1) to keep after-meal BG under 140 and fasting BG under 100. My last A1c was 5.9.

Recently when I was out of Lantus due to insurance screwup, my FBG went up to the 140 level. Aargh!

So I dearly hope you're right about these Lantus studies. I like the tight BG control I am able to get with Lantus.

Jenny said...


Levemir gives people excellent control, too. I have seen several people switch to Levemir from Lantus because they were gaining unwanted weight from Lantus.

So that's an alternative.

What's really sad is that they stopped making the long-acting version R insulin, Ultralente, which I personally did very well on. It went out of use precisely because people switched to Lantus. NPH is much shorter in action and much more likely to cause hypos.

Anonymous said...

And what blesses (cursed) set of laws keeps generic insulin off the market. I think I know, but what I don't know is the politics of it not changing. RobLL

Anonymous said...

EPA States

Several animal studies suggest that o-cresol, m-cresol, and p-cresol may act as tumor promotors. EPA has classified o-cresol, m-cresol, and p-cresol as Group C, possible human carcinogens.

These added preservatives are found
in many Insulins Sold

jimpurdy1943@yahoo.com said...

"Remember that cancer cells require a lot of glucose to grow."

For some reason, just the possibility of cancer scares me more than the very real damage that my Type 2 diabetes is already doing.

I guess I'm going to have to work even harder on controlling my diabetes.

Jenny said...

The cresols are in all the insulins including the R which did not, apparently, show heightened risk of cancer.

I doubt the tiny amount of cresol in the insulins is anywhere near as dangersous as the preservatives in our food supply--or the plastics.

Anonymous said...

It seems like this is an old issue that is now resurfacing.

Ive covered in my blog at http://dandtheguy.com/2009/06/29/lantus-may-cause-cancer/


Author of D and The Guy

Anonymous said...

I am a 35 yr old type 1. I will be switching back to levimir which i did just fine on, until my endo decided she liked lantus. (not because of a diff in numbers she saw, she just "trusted" it)I wish dr's would listen to patients more often!!!

Katie said...

My hubs just had his pancreas removed - immediate type 1. I've been looking for sites..., Glad I found this one. I'll be checking out the rest of it - thanks

Anonymous said...

When you look back on the beef pork insulin, they worked better than most of the dna insulin today with much less risk. Why did they stop making them?

Jenny said...

Dr. Bernstein has said that the animal insulins were not better for many people because they caused allergic reactions. They were much slower in action which gave more warning of hypos, but their activity curve made very tight control difficult.

Back when they were in common use doctors routinely kept the blood sugar of people with Type 1 very high on purpose. It was only in the early 1990s that DCCT found that this was causing complications.

There are some people they still work best for, but my impression is that they are people who are eating very high carb meals for whom the slowness of the animal insulin makes it easier to avoid hypo. Plus people rarely become allergic to the newer insulins.

Anonymous said...

I'll go back to Levemir. It is once daily and no weight gain

Jenny said...

Levermir is only once daily in larger, Type 2 size doses.

But Lantus doesn't cover a full 24 hours for many people with Type 1, either.

JennyO said...

At least, Sanofi did take a stand :


sooz said...

If you aren't already doing so, lower your carbs folks!! Mostly that translates to needing less insulin too.

No matter what these studies show (thanks Jenny, as always, for the intelligent analysis), using less insulin, while keeping your blood glucose within your target range, has other benefits too, not the least of which may be in reducing any risk of long-term use, whatever those risks may turn out to be.

There may indeed be no risk at all. Definitely far more risk from not using these analogs.

Anonymous said...

The possible relationship between Lantus and cancer has nothing to do with high blood sugar levels. The main area of concern every health care provider should be made aware of is the unique IGF characteristics Lantus has that no other insulin on the market has. IGF or Insulin Growth Factor (for our purpose in this discussion describing insulins) is a term used to describe the affinity or degree of attraction an insulin molecule demonstrates in clinical testing to bind not to the Insulin Receptor Site on any given cell (allowing cellular uptake of glucose), but rather to bind onto the IGF-1 receptor site. This insulin to IGF-1 receptor binding promotes "growth" not glucose uptake. Now every insulin has a different IGF characteristic. Human insulin is considered the gold standard in IGF properties which is about 100. Lantus' IGF properties are more than 6 times this (641). With an insulin molecule that is more attracted to the IGF receptor you will get more cellular growth. Potentialy promoting the growth of cancer cells. However, we have insulins that lower blood glucose just as good and better than Lantus available. NPH, not liked too much anymore because it's dosed twice daily has a low IGF. Levemir, a once-daily basal, having less weight gain associated with it's use, has the lowest IGF at around 16. All we can do is wait and see if the FDA slaps a black box warning on Lantus or not. Until then, keep using your insulin, call your doctor if you want to be switched to Levemir or NPH, and then if nothing comes from this go back on your Lantus.

JC Lynch said...

To say that Family Physicians don't have the same resources as endocrinologists is more than misleading. Many physicians prescribe basal insulin only to patients with type 2 because that is what the data support as being equivalent or superior. Three times a day insulin in patients with type 2 leads to more weight gain without additional A1C reduction in most patients when compared to basal insulin plus metformin. Also to say that NPH is much more likely to cause hypoglycemia is NOT true. It is slightly more likely to cause nocturnal hypoglycemia than Lantus, but only by a VERY small percentage. And Ultralente went off the market years before Lantus come into clinical practice, primarily because it was very expensive to make and virtually no one was using it. It is still available as an orphan drug from Eli Lilly.

I am not affilliated with any drug company and am a professor of pharmacology. I hate reading these misleading statements in blogs.

stevem said...

Can someone please help answer my questions below.

I am a 38 year old make who has had type 1 for 5 year.

I first used NPH, but didn't like how short it lasted or the weak control it gave me.

I have been using Lantus for 4 year and like the control it gives me.

I also like how long Lantus last, 24 hours, so I can give the shot at the same time each day.

But this study worries me.

Could some one tell me if 1 unit of Lantus = 1 Unit of Levimir?

Any does Levemir last the same length as Lantus?

Any educated answers would be appreciated.


Jenny said...


My guess is that the reason for the Cancer/Lantus finding is that they were comparing people using very large doses of Lantus with people using small doses. All insulin, including the insulin your body makes is a growth hormone and may promote cancer, so people using huge doses would be expected to see slightly more cancer than people using small doses. This is one reason to do what you can to lower insulin resistance and to use as little insulin as you can, which means cutting way back on carbs even if the insulin helps cover them.

That said, the evidence is not strong for the Lantus/cancer connection based on these studies and people I respect are saying not to panic.

The answer about how Levemir compares to Lantus depends on how much you are using. The smaller the dose, the shorter the time Levemir lasts. In some type 1s it lasts about 12 hours and they use two shots. But in the same size doses many Type 1s find they need to split their Lantus doses too as it doesn't last 24 hours.

Levemir is fairly new, so we have no longterm studies to tell us what its side effects are.

All this is one more reason to be furious that Lilly took Ultralente off the market. That was a regular human insulin with a much longer activity curve than NPH and without the fish proteins NPH contains.

In larger doses such as Type 2s use, Levemir may be dosed the same as Lantus and last 24 hours. You won't know until you try it. Levemir is supposed to cause less weight gain than Lantus, which is one reason to prefer it.