How Biosimilars Are Shaping RA Treatment and Reimbursement Strategies

In this episode of Pipeline Projections, Roy Moore—Senior Healthcare Research & Data Analyst at Clarivate—discusses the expanding biosimilar pipeline for autoimmune diseases. He highlights recent FDA approvals, formulary and pricing strategies, and the growing impact of biosimilars on payer decisions, physician adoption, and treatment pathways.

Let’s start with an overview—what’s the current landscape of biosimilars in the US Food and Drug Administration (FDA) approval pipeline, particularly for autoimmune diseases such as rheumatoid arthritis?

Roy Moore: First of all, thanks for having me. When they first came out with a pathway for biosimilars, the immunology space was probably one of the first places people were going to be looking for, and that's primarily because you had drugs like Humira that were market dominant and, of course, would fall under biosimilars.

We actually have seen some change and some evolution in the biosimilar space for RA and for related diseases. We saw infliximab and rituximab, which have already had biosimilars launch, and multiple biosimilars for each of those molecules are on the market. We saw, just a couple of years ago, the first Humira (adalimumab) biosimilars launch, and there were a slew of those on the market as well. That was the big one that we were looking at.

We do expect biosimilars to continue to evolve in this space. We did just see the approval of a few Actemra biosimilars. Those are starting to launch. We're expecting biosimilar versions of Simponi ARIA (golimumab) to launch in the next year.

Of course, in the decade, we're looking at Cimzia (certolizumab pegol) and Orencia (abatacept). They'll have biosimilar competition reaching the market. It's a pretty dynamic space for biosimilars when it comes to RA and autoimmune disorders.

How might these emerging options impact the competitive dynamics of other treatments already available in the space?

Moore: Payers love biosimilars because they create competition, and that pushes net pricing downward. That's where you're going to see it at a high level, the net price of all drugs will go down. Not the list price necessarily, but the net price that payers pay. You'll see rebates increase. I do want to look at this a little bit from both the originator and biosimilar perspectives, and then separately, from all the drugs in the category.

What you'll see when these drugs launch is that payers will choose to pick one or a few originators to reimburse and then exclude all the rest. They'll do that based on if they deem the drug as efficacious enough, effective enough, and they'll do it based on net pricing.

Their influence will extend beyond, of course, the originator drug itself and the biosimilars. It will extend to the entire category. As I said before, you'll see a push for net pricing to come down, and that's because you'll see the biosimilars be used as the price comparator. Now you have a new anchor that's going to be lowering prices in the minds of payers.

They're going to be, obviously, using that to extract greater rebates from the manufacturers of other drugs in the category. That being said, you'll also be seeing some payers putting their preferred biosimilar as a step—via step therapy—for certain drugs. For instance—and I know this is not RA, but it's a related disease—in the case of psoriasis, Siliq (brodalumab): we know that UnitedHealthcare makes you step through one of the biosimilars for adalimumab before they'll reimburse Siliq. So, you can see how the rise of biosimilars affects other drugs in the category, even if they aren't necessarily the same molecule as the biosimilar itself.

I do think it's important to point out that drug companies are not dumb. They know this stuff is coming, so they plan ahead. A great example would be AbbVie, they make Humira. We knew that biosimilars were going to be coming for that drug for years. What AbbVie did was they tried to prop up support for Humira, even though biosimilars came through greater rebating, but then they had another tactic, where they were trying to push their alternative drugs in the categories—Skyrizi (risankizumab) and Rinvoq (upadacitinib). If you look at their 10-K, you can see last year that sales of Humira cratered, but sales of Rinvoq and Skyrizi skyrocketed.

That, obviously, was not happenstance. That was part of the strategy to fend off competition for biosimilars for Humira so they could shift patients over to the newer drugs.

Several biosimilars to tocilizumab (Actemra) are advancing through the FDA pipeline. What are the most notable candidates, and how could their entry reshape treatment patterns and potential coverage strategies?

Moore: Speaking of Actemra, we know that there are biosimilars in development, but before I dive into that, I did want to take a step back and examine what makes Actemra unique and how that will play out with terms of market access.

Unlike, say, a drug like Humira, Actemra has 2 types of administration. One is subcutaneous, administered by the patient at home. That drug is typically covered under the pharmacy benefit. There's also an intravenous (IV) version that's physician administered. That will typically fall under the medical benefit. That distinction is going to be important when it comes to coverage of these drugs.

We know that there are some biosimilars in development. Biogen had one that was approved in September 2023, but that was just IV. Fresenius has one that was approved May of 2024, but that was IV and subcutaneous. In February 2025, just a couple of months ago, there was one for Celltrion. That should be coming out in August, later this year. I'm sure there are others in development, but typically what we find is that, when it comes to biosimilars, being first to market is usually important because payers don't necessarily distinguish between the different biosimilars, first to market helps.

As I said before, there was an IV version, the one from Fresenius. The drug is called Tyenne. It's reimbursed, according to our data, as a medical benefit, and it looks like all the payers are paying for it under medical benefit. That's important, as I said, because there is a distinction when it comes to biosimilars that are physician-administered vs those that are self-administered.

When it comes to a self-administered drug like adalimumab, as I said before, payers will only cover a certain number of drugs because they want to drive up rebates for those drugs, for those biosimilars, and then exclude the rest. That's not necessarily the case when it comes to IV drugs, because there's a different mechanism of play there. There's a thing called practice economics that you have to keep in mind when it comes to the providers. When you have a biosimilar that's for an IV drug or physician-administered drug, and it falls under medical benefit, what you will find is that the payers will typically reimburse all the drugs.

We see this for the infliximab biosimilars. The payers will reimburse all the drugs under the medical benefit, and they will try to favor one over the other, but they'll cover them all. The reason for that is that drugs that are physician-administered qualify for buy and bill. That means manufacturers can contract with the physicians themselves to give them rebates if they hit certain prescribing targets or growth targets. So, if you're a practice and you decide to only stock one biosimilar, you can get 5% back if you hit certain volume levels.

That becomes a cost driver. It becomes an influencer on physician choice. A lot of times, the payers do not want to get in the way of that because, in some cases, some of these practices aren't terribly profitable and they rely upon the profits they can get from buy and bill in order to make ends meet. We do see a difference there.

That being said, we do expect biosimilars for Actemra to have an impact on the market, again, similar to what we've seen with Humira. You'll see competition among what you cover under the subcutaneous version, and then probably openness, as we see with infliximab.

What key clinical or economic data should payers be watching for as these biosimilars move toward approval? Are there any early signals of differentiation that stand out?

Moore: When the drugs are in development, the first thing payers are going to look at is the trial design. When it comes to biosimilars, you're typically showing noninferiority vs the reference drug, and that's typically going to be the case. Of course, there will be other endpoints that can be used to differentiate the drug. But, at the end of the day, the data are going to come out to say that you're noninferior.

If you do have data that show you're better, then you're considered what's called a biobetter. That's a different ball game. But if it is just a noninferior product, then payers tend to look at these drugs as commodities, and in commodities, they see the drugs are all the same. I've had payers tell me that they don't even necessarily look very deeply at the clinical data. They will say, "If the FDA approved it, then it's good enough for me, and it should good enough for the physicians, because they're the ones who have to decide this." That's the clinical data they're looking at. It's not even very deep, because again, you're showing noninferiority and you're relying upon the FDA to give the seal of approval.

But these drugs are now seen as a commodity, and that's where the economic data comes in. That is something that payers definitely will dive into. What we're going to see is that, when these biosimilars launch, they will launch at a discount to list price for the reference drug. Maybe 15% for the first drug, or 10%. Each subsequent biosimilar will have a bigger decrease in the list price, but that's not where the action is. In RA, as with all immunology, it is extremely heavily contracted. By that, I mean manufacturers are giving rebates back to payers that are pretty sizable, north of 20%, probably much more than that in some cases.

Although these drugs will have different list prices, the net price will be vastly different because the manufacturers are going to be on formulary, and they want to be the only one on formulary. They're going to give back richer and richer rebates. What the payers are going to say is: “What can you give me? I'm only going to cover 2 of these drugs. What's the best deal you can give me? If you can give me that, then you get all the business.” That's the data they're going to be looking for, what the net pricing is going to be. There could be other factors that influence things, such as any kind of benefits programs that may help, but it's really going to come down to net pricing at the end of the day.

What are the biggest challenges when integrating new biosimilars for RA into formularies?

Moore: When biosimilars come to our markets, it kicks off an era of change for the entire category. It's multistep, and I'll try to walk you through all the different steps. It does create challenges.

First of all, you have your formulary that's set up for the year or for the half year. You have your contracts in place. When there is a biosimilar coming to market, oftentimes, you'll see the manufacturer of the originator have a multi-year rebate contract in place, so they could fend off rivals right away. You may not see changes to the formulary at the get-go.

But let's say now that time has passed and you're a payer, and you have to you decide what you're going to cover. You need to decide how many biosimilars do you want to cover. What strategy do you want for that, and who do you prefer to contract with? Because although there are a lot of companies that have biosimilars, they may have varying reputations.

That's not to say any company is bad, it's just some are very experienced in the space. If you see like a Teva, obviously you're dealing with a high-end company. Same with Sandoz. There may be some companies that are smaller that you are not familiar with, and that's going to have an influence on whether or not you want to be in business with them.

From a payer standpoint, you want to decide which ones you want to contract with. You want to check the data. Is there anything with a trial that stands out that you need to worry about? Or you can just rely upon the FDA approval. You need to ask: Do I trust them with their supply chain? Will this drug run out? Is that going to be an issue? That'll be an issue they're looking at as well.

And then they have to start contracting. As I said before, this is an extremely heavily contracted category because we have a lot of preferred coverage. We know that, so we know that there's a lot of contracting. We know the rebates are north of 20%, much higher in some instances.

You have to know who you're going to get in business with and what the contract is going to be. As I said before, in some cases, the manufacturer of the originator will up their rebates to fend off competitors. That's a discussion point and a challenge that the payers have to overcome as far as do they want to continue to do that? Or do they want to go full blast and full freight right into the biosimilar space?

Let's say they want to do a biosimilar. They're going to focus on the best rebate for the drug, and it's not just for that drug. What you see with some of these companies is that they have multiple drugs in the category. Not necessarily multiple drugs for the same molecule, but for the same category.

An example would be that Pfizer has developed biosimilars for both biosimilar versions of Humira or infliximab. We know from our data that they are very aggressive on rebating. You can set up a contract that covers multiple drugs in the same therapeutic area, or you could even do it across therapeutic areas. That's something that the payers will be looking at as well to decide what they want to reimburse. You may take lesser rebate on this one drug if the combined rebate of all the drugs is greater.

That being said, they decide to contract with a certain manufacturer, and they put the drugs on formulary, but that's not actually where the challenges stop. You have to get the physicians who use the drugs. Unless the biosimilar is considered interchangeable, you can't simply have the pharmacist switch without notifying the physician and having their approval. You really need buy-in from the physicians.

Now, this was an issue in the early years of biosimilars where we saw there was some physician skepticism around biosimilars, but that's been largely assuaged. That's probably because they've had more experience with biosimilars, but also, payers have put a lot of effort into educating physicians ahead of biosimilars coming, doing a lot of lunch and learns, a lot of training. They say, "Biosimilars are coming and we're going to be switching. Here's the data on it. Here's how you can get familiar with it."

They want to make it a fluid situation and to not hurt the physicians. They see the physicians as their partner. This is particularly the case if you have a therapeutic area where there's a physician shortage and the physicians have all the power. But they do want to see the physicians as partners. So, to assuage any kind of pushback from physicians or from the patients themselves, what they'll typically do is they'll do a stepped approach.

Let's say I signed a contract today for a biosimilar and I say, "Okay, all new patients, all patients who are treatment-naive, have not received treatment, will start receiving the biosimilar as of July 1st. That's the drop-dead date. No one else can change. For existing patients who are already receiving the reference product, you can go on until the beginning of next year." That should give physicians enough time to familiarize themselves with the biosimilar, to get greater comfort with it, so that they can switch them over.

That's typically how the payers are handling this, because you can't necessarily switch patients over immediately without physician approval unless you have interchangeability designation.

Those are some of the challenges that you see. But, by and large, we've seen the learning curve for biosimilar adoption by payers and physicians improve. There was a slow uptake, but we've seen a lot of improvement because of the outreach by the manufacturers of the biosimilars, but also the payers to make sure that physicians are on board so that patients are on board as well.