Are Basaglar and Lantus the same?

Are Basaglar and Lantus the same?

Basaglar and Lantus are considered by some countries to be biosimilar biomedical products, and often called biosimilar by online writers – although they are not considered biosimilar by the US FDA. What exactly does this mean? Will they function the same for you?

Basaglar is often called a generic version of Lantus – but is not. What is a generic medicine? Why is Basaglar not a generic?

The responses to these questions can be subtle, and requires the use of very specific vocabulary in the context of medical drugs: “biological”, “generic”, “biosimilar” and “interchangeable.”

Biological vs conventional drugs

A biological drug is different from a conventional drug. A conventional drug has a specific, simpler chemical composition that is exactly the same across all examples of this drug, and that is clearly defined. it is typically (although not always) produced as the result of a chemical reaction. The FDA writes: “Conventional drugs are made of pure chemical substances and their structures can be identified.”

On the other hand, to quote the FDA: "Biological products are made from living organisms […] Biological products are manufactured through biotechnology, derived from natural sources or, in some cases, produced synthetically.

“Most biological products are more complex in structure and have larger molecules or mixtures of molecules than conventional drugs (also called small molecule drugs). […] Most biologics, however, are complex mixtures that are more difficult to identify or characterize.”

Similarly, the UK NHS writes (PDF): “Biological medicines are derived from living cells or organisms and consist of large, highly complex molecular entities which may be difficult to characterize. Due to the variability of the biological system and the manufacturing process, biological medicines may show a certain degree of variation, even between batches of the same product.”


A generic drug is an exact chemical copy of a conventional (small molecule) drug that, in general, used to be patent-protected, but whose patent protection has run out. The approval of a generic drug approval by a regulatory agency means hat its manufacturing process is reliable enough to provide a high certainty of the quality of each of its batches.

Biosimilar biological drugs

There are no “generic” biological drugs. The closest equivalent concept is “biosimilar.” This is how the US FDA defines “biosimilar”:
“A biosimilar product is a biological product that is approved based on a showing that it is highly similar to an FDA-approved biological product, known as a reference product, and has no clinically meaningful differences in terms of safety and effectiveness from the reference product. Only minor differences in clinically inactive components are allowable in biosimilar products.”

The UK NHS explains (PDF): “A biosimilar medicine is a biological medicine which is highly similar to another biological medicine already licensed for use. It is a biological medicine which has been shown not to have any clinically meaningful differences from the originator biological medicine in terms of quality, safety and efficacy. Biosimilar medicines are not considered generic equivalents to their originator biological medicine because the two products are similar but not identical. However, they will have met regulatory requirements in terms of comparative quality, safety and efficacy.”

Therefore, biosimilar drugs are biological products that have the active part of their chemical composition largely identical to that of a reference product, but which are possibly or likely, as a whole, chemically different, and which have been shown by clinical studies to be statistically equivalent to the reference product for most patients.

Interchangeable biogical drugs

This does not mean, however, that biosimilar drugs have been shown to be functioning similarly for all patients. For that, there is another word, “interchangeable.” Again, the US FDA writes:

“An interchangeable biological product, in addition to meeting the biosimilarity standard, is expected to produce the same clinical result as the reference product in any given patient.”

Basaglar vs Lantus

Lilly, which produces Basaglar, states that “BASAGLAR is a long-acting insulin with an identical amino acid sequence to Lantus®”, which means, at the very least, that the active part of the drug has the same chemical sequence as Lantus (although it may not be, for instance, geometrically the same, and therefore could have difference properties). The UK National Institute for Health and Care Excellence (NICE) calls Basaglar (Abasaglar in the UK) a biosimilar to Lantus, and has documented clinical study results that prove it: “In 2 randomised controlled trials (RCTs) insulin glargine biosimilar (Abasaglar) was as effective as insulin glargine (Lantus) at reducing HbA1c levels in people with type 1 and type 2 diabetes. The safety profile of Abasaglar is comparable to that of Lantus.”

The US FDA does not call Basaglar a biosimilar to Lantus for regulatory reasons, because Lantus was not introduced under the Affordable Care Act (a requirement for the reference product if the follow-up product is to be called biosimilar for the US FDA). But it is likely that it is considered as such: “The applicant demonstrated that Basaglar was sufficiently similar to Lantus to scientifically justify reliance, and also provided Basaglar-specific data to establish the drug’s safety and efficacy for its approved uses. […] Basaglar is not approved as a biosimilar product. No insulin glargine products are currently licensed under the Public Health Service Act, so there is no “reference product” for a proposed biosimilar product.”

However, there is no evidence that Basaglar would be an interchangeable product to Lantus.

So, our conclusion should be that:

  • Basaglar is chemically close to Lantus but may not be the same

  • Statistically, Basaglar behaves in the same manner as Lantus for groups of people. So it is likely that it would behave the same for you.

  • It may not behave the same for individuals. So there is a possibility that you could be an exception to the statistics.


US FDA on biosimilars (1):
US FDA on biosimilars (2):
UK NHS on biosimilars (PDF):
Lilly Basaglar introduction:
FDA Basaglar temporary approval announcement:
UK NICE Abasaglar Evidence Summary:

End of wiki post ---------- Comments start here.


This sounds a bit like semantics though.

Am I reading this correctly? That it is basically the same, but it just can’t be called that?

I know that Levemir and Lantus are extremely different in their structure, although their curves are believed to be somewhat similar, so they would never be called the same.

1 Like

You did not read it right:-) A biosimilar drug is not the same as the reference drug. What this is saying is that the FDA cannot call Basaglar biosimilar – but if they called it biosimilar it still wouldn’t be the same drug.

I think I did.

“Only minor differences in clinically inactive components are allowable in biosimilar products.”

So for all practical purposes, a biosimilar drug is essentially the same.

Will biosimilars and interchangeables work in the same way as the biological reference product they were compared to?
Yes, biosimilars have no clinically meaningful differences in terms of safety and effectiveness from the reference product they were compared to.

“The US FDA does not call Basaglar a biosimilar to Lantus for regulatory reasons, because Lantus was not introduced under the Affordable Care Act (a requirement for the reference product if the follow-up product is to be called biosimilar for the US FDA). But it is likely that it is considered as such”

I read the whole thing. When I take all of this in context of the FDA and pharmaceutical lawyers, my takeaway is that these two insulins are as close to one another as possible, without being tagged the same.

And part of argument for that is this sentence:
“Basaglar and Lantus are considered by some countries to be biosimilar biomedical products”

I think the regulatory agencies of other countries probably have a great deal more sense than our beloved FDA.

The more I look, the more it just sounds like lawyers to me. I’d like so see which countries do consider it biosimilar. I think there are a few countries that are bosses with insulin, like Denmark maybe.

BASAGLAR is a long-acting insulin with an identical amino acid sequence to Lantus®

The FDA approval follows BASAGLAR’s tentative U.S. approval in August 2014, which was contingent upon patent litigation resolution. Per the settlement agreement with Sanofi, BASAGLAR will be available in the U.S. starting on December 15, 2016.

Clinically meaningful has statistical meaning only, it is not a characteristic of a physical description for the drug. It does not perfectly reflect what it will do to you – it can also have missed groups of people with specific characteristics (for instance, to take an example, there could easily be differences in two biosimilar substances when they apply to diabetics who also have celiac disease. The average study only covered 500-800 people, so it is easy to miss a smaller pattern with these numbers.

In the end, biosimilar products can be widely different in some ways that are not always apprehended by the clinical studies they undergo. As @Chris says, it is almost a miracle that there CAN be biosimilar products.

They can easily be identical in chemical composition but physically different - that is common in organic chemistry, or they can have same amino-acid sequences but different end compounds (that may not be amino-acids).

A very simple example: what about comparing all the pure carbon compounds: diamond, graphite, graphene etc.?

The way Lantus works is with higher order aggregates of insulin hexamers that unwind slower. The sequence is the important part.

I understand they may not be identical, my debate is whether it is practically the same, so similar that it is not even worth trying as a different medicine.

Do you have any idea which countries call it biosimilar? I value what the Danes say about insulin. But tracking down that stuff is hard enough when you are searching for your own country’s classification. What do the French say? The Swiss? The Germans? The Canadians? To me that would be interesting. I just wonder if the U.S. is on its own.

Think about Fiasp - available in Canada, available in the 28 European Union member states. But not here! They have filed for review here. Certainly it is because of the overwhelming process our FDA puts on that sort of thing that we have to wait.

1 Like

But how do you know about the geometry and the physical properties? I am not saying it is not going to work the same for you, of course. What I am saying is that biosimilar does not mean the same, and that we don’t know for sure until it has been tried by tens of thousands of people :slight_smile:

I know England does. Does it mean that possibly the rest of Europe does? I am not sure.

The problem with insulin is that quantifiable measurements are impossible without putting someone in a lab. And for basal insulins, it is even more difficult. Instead of being stuck next to a glucose infusion machine for 4 hours, someone would need to be connected to it for 12-24 hours.

All the reports are just anecdotal evidence. So we will never actually know.

Think about Humalog and NovoLog. People might switch from one to the other, and then say it didn’t work well for them. But think about all the bad days you might have for a million different reasons. How does someone know it is the insulin that caused the problem instead of something else? Without being in a lab, we never really know.

So the cool thing is that we are having a debate on the potential differences, and it is a debate that will probably never end. So we are just trend-setters. :wink:


To summarize, they’re “pretty much” the same exact thing;) right?

I think for most people you would expect them to be. We haven’t started on Basaglar yet, but I expect it to be nearer the Lantus experience than switching to Levemir would be.

1 Like

Really hope you try tresiba… its next generation stuff

We definitely will. But remember we deal with daily variations of 50% TDD or more right now, as, I believe , does @Chris. For instance, yesterday = 38, the day before = 26, today could be 45 – or 24 (well, I already know it won’t be low…).

Yes that’s your reality now and the fact that you have a basal that behaves more erratically than tresiba isn’t helping to clarify that puzzle either… I think you’ll find more clarity with an ultra long acting and completely predictable basal and pursuing the oddball corrections in the bolus realm…

While I would agree that Basaglar and Lantus are not identical, I think you could say “close enough” or “practically the same”.

Levemir and Lantus however are very different in how they are made to release, either being precipitated into the tissue slowly (Lantus) or slowly unbinding from the albumin in the blood (Levemir). There is not really a claim that they are the same, only that the effect of the two of them are similar.

When it comes to any insulin, asking which is better is like asking an auto mechanic whether a wrench is better than a screwdriver. It kinda depends, doesn’t it?

For Sam, Tresiba is great. For me, it would practically be a death sentence. Without being able to adjust daily, I’d be screwed. Eventually I’d end up in a ditch.

For any basal insulin, try it. But keep in mind that it depends on individual needs. Are you a flat basal type or do your basal needs vary depending on the time-of-day? Do your basal needs stay the same one day to the next, or are they different depending on the day?

I think it is important for everyone here to recognize that terms like “better” or “best” are only appropriate in context of the individual.

There is no “best” basal insulin, only one that is “best for you”.


While I agree with you, it is important to realize that many people don’t really understand their needs and frequently frame their observations incorrectly in their minds, and it is easy to misinterpret our own observations, particularly for people who haven’t been doing this for as many years as you have … as I’ve explained before it was my own “variable basal needs” that, interestingly, led me to tresiba and much improved stability with it.

Point being that I think it is always best to try things to determine if they fit well for us instead of trying to reason our way through it without trying it


I agree wholeheartedly (says the guy who has tried 8 different insulins in the past few months…).

1 Like

Our TDD is all over the place as well. That said, our basal rates are reasonably similar. Although we frequently turn down the basal when we have lows, when activity increases, and when the moon phases are in alignment…ok just kidding about the moon phases. I really like the pump for this, and don’t think we would have as good as control without a lot more prior planning.


My insurance company has changed and they will only cover Basaglar and not Tresiba. My regime has been very satisfactory with Tresiba and Novolog MDI, A1C 6, for about the past 2 years. The insurance company is now dictating that I switch to Basaglar, and Accu chek (previously Freestyle Lite), decrease the number of times that I can check my BG… yuk. I’ll keep you all posted as to my personal experience with Basaglar. I still have some reserve Freestyle Lite strips. Therefore, the only “change” will be the Basaglar. I have a relatively stable routine, most of the time.

1 Like

A lot of these things can be appealed.

The insurance company hopes you won’t bother, but you might be able to get approval.


Yes for sure appeal it, PA it, whatever it takes… sure basaglar will work fine but tresiba just makes life so easy

1 Like