Is the 505(b)2 Pathway Viable for Biosimilars?

With regulators focused on streamlining the 351(k) biosimilar development, it makes sense to wonder if the 505(b)2 pathway is valid for biosimilar approval.

Can discussions about streamlining biosimilar development reach into abbreviated approval pathways for small molecules? Based on a Stat News webinar I attended yesterday, they already have. What exactly are the differences between the 351(k) pathway for biosimilar candidates and the 505(b)2 pathway for small molecules?

Biosimilar-Type Products Already Approved Through the 505(b)2 Pathway

The 505(b)2 pathway was used for some products that are considered by most as biosimilars today. For example, Basaglar, the first copy of insulin glargine, was approved in 2015 through this pathway; it was before insulins transferred to the biosimilar pathway for approval in 2020. Admelog was the first insulin lispro copy, approved in 2017 through the 505(b)2 pathway as well. However, Granix, the first filgrastim molecule launched that was not Epogen or Procrit, utilized the 351(a) pathway, meant for innovator biologics; it predated the implementation of the 351(k) route to approval.

With streamlining of biosimilar development—a major focus of regulators today—it makes sense to wonder if the 505(b)2 pathway is a valid goal for biosimilar manufacturers.

Infographic comparing 505(b)(2) drug approval and 351(k) biosimilar pathways

The 505(b)2 application pathway was implemented through the Hatch–Waxman Amendments of 1984. It was not meant as an abbreviated pathway for generics, but rather a streamlined way to bring new forms of existing innovative medications to market. These are commonly referred to as “follow-on” products. The basis for its use is that the innovator product on which the follow-on molecule is based has a truckload of patient experience proving its safety and efficacy. The manufacturer would simply have to show that its product was very much like the innovator. Its application could range from new formulations, strengths, to other modifications that wouldn’t be expected to affect the structure or anticipated effectiveness.

According to Drug Patent Watch, development cost of a 505(b)2 product might be anywhere from $8 million to $20 million, and the timeline to reach the market (not counting patent litigation) could be as short as 3 years. The 505(b)2 pathway allows a manufacturer to utilize the innovator product’s preclinical and clinical data, requiring little more than comparability studies and bridging pharmacokinetic studies to reach the FDA application stage. The FDA may still require a phase 3 trial, which would change the costs dramatically, but it appears attractive in any case.

Of course, biosimilars require a bit more consideration, as they are far more complex than small molecules, for which the 505(b)2 pathway was intended. With the push to streamline biosimilar development, including waiving the phase 3 trial mandate, eliminate separate testing for interchangeability (and eliminate the designation itself), and drop the need for bridging studies, it is not difficult to visualize movement in this direction.

The Difference With Insulin as a Biosimilar

Yet, insulin is a relatively simple biologic molecule. It has decades of use and clinical experience supporting its safety and efficacy. When the 505(b)2 pathway was used to approve Basaglar and Admelog, few considered this a big risk (it may have helped that the first biosimilars were already approved and in clinical use).

Biosimilars are not follow-on products, unlike typical 505(b)2 agents. Rather, biosimilar manufacturers strive to make their candidates as close a copy as possible to the innovator (but realizing an exact match is impossible). Logically, it might seem that the biosimilar approval process should be at the same level of proof as the 505(b)2 pathway. No, that can never be the case—the structure of biosimilars will always be a little different than the innovator agent. And the structure will always change a bit over time (as will the innovator biologic).

It is better, instead, that the 351(k) pathway is modified to reflect the real-life experience of the biosimilars approved to date by the FDA and the EMA, and that does provide ample opportunity for lowering the bar, and costs, of development.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA. 

First Opdivo Biosimilar FDA Application Submitted by Amgen

Amgen became the first manufacturer to submit an application to the FDA for a nivolumab (Opdivo) biosimilar. It also was the first to be sued for patent infringement.

Last week, Amgen became the first manufacturer to disclose that they submitted an application to the FDA for a nivolumab (Opdivo) biosimilar. In doing so, Amgen also became the first manufacturer to be sued by the reference manufacturer Bristol-Myers Squibb for patent infringement.

The company disclosed the 351(k) application during a business presentation on September 10. Amgen’s product, ABP 206, is one of several publicly disclosed nivolumab biosimilar candidates. The company reported, “...for ABP 206, our biosimilar candidate to OPDIVO, our Biologics License Application with the FDA has been submitted and accepted for review. We expect an FDA action on that BLA by end of the year.”

Net 2025 US revenues for Bristol-Myers Squibb’s PD-L1 inhibitor were $5.9 billion. The intravenously administered drug was first approved in 2014 (and market exclusivity ends this year), and its main patent expiration is expected to expire in 2028. Bristol-Myers Squibb also introduced a subcutaneously administered version of Opdivo in 2024, which is approved only for specific cancers. Among other manufacturers who have publicly disclosed potential nivolumab biosimilars Sandoz, Xbrane, Henlius, and mAbxience, are in various stages of development.

Patent Infringement Suit Filed Against Amgen’s Opdivo Biosimilar

Within days of the announcement of Amgen’s FDA biosimilar application for ABP 206, Bristol-Myers Squibb initiated a lawsuit claiming infringement on at least 7 patents on their product. We estimate the earliest expected launch date for intravenously administered nivolumab biosimilars to be in 2029 based on a main patent expiration in late 2028. Based on past experience, the likelihood of a settlement between the two parties may be lower than for other prospective biosimilar manufacturers, as Amgen has been willing to go at-risk for launch in the past (specifically for its aflibercept biosimilar Pavblu, a product with a similar market size as nivolimumab).

Of further interest, Opdivo is often prescribed in combination with Yervoy (ipilimumab), which is also the focus of considerable biosimilar research (also involving Amgen).  Amgen also disclosed during its business presentation that it intends to file its biosimilar application for ABP 234, its biosimilar candidate to compete with Keytruda, before the end of the year.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA. 

Biosimilar Bytes: Alvotech Biosimilar News and 6-Month Ustekinumab Switching Outcomes

Alvotech has a new vedolizumab BLA and new marketing partner, and Stelara biosimilars produced equivalent clinical outcomes to the reference product over 6 months of treatment.

Alvotech’s Second Application for Vedolizumab Biosimilar and New Marketing Partner

Alvotech announced that the FDA has accepted its 351(k) application for a prefilled syringe and autoinjector formulation of vedolizumab. This product, dubbed AVT80, follows Alvotech’s previous submission of an FDA application for AVT16, the intravenous formulation of the same integrin inhibitor. According to a company Email to BR&R, Alvotech utilized two separate compound designations for this Entyvio biosimilar, because the reference compound was approved under two separate biologic licensing applications. Teva is the marketing partner for both formulations. The second vedolizumab biosimilar application, submitted to the FDA by Fresenius Kabi and Polpharma, was for the intravenous formulation only.

Alvotech marketing agreement

In separate Alvotech news, it has signed an agreement with Lotus (and its US-subsidiary Alvogen) to market AVT34, a proposed duravalumab biosimilar, and AVT 87, a proposed emicizumab biosimilar. Duravalumab (Imfinzi) is a PD-L1 inhibitor, with multiple cancer indications. The major patents for this product may not expire until after 2035. Emicizumab (Hemlibra) is a bispecific factor IXa- and factor X-directed antibody to prevent bleeding episodes in patients with hemophilia A. First marketed in 2017 as well, this product’s main patent expires in 2032, according to sources. The agreement is not exclusive, and may result in Alvotech also marketing these products in the US. In addition, it applies to selected Asian markets.

Stelara Biosimilars Work Well in Italy, With Little Switching Back

An Italian study published online in Clinical Gastroenterology and Hepatology found that switching from Stelara to ustekinumab biosimilars resulted in equivalent success rates (92%–93%) in 337 adult patients with Crohn’s disease after 6 months of treatment. The study group was compared with 125 patients who continued to take the reference product. Only 1.2% of patients switched back to the reference product. The authors noted that longer-term data would tell a more comprehensive story for this chronic therapy.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA. 

The Second Entyvio Biosimilar Is Under Review at FDA

On July 31, Fresenius Kabi and Polpharma Biologics announced that its 351(k) application was accepted by both the FDA and the EMA for PB016, a proposed vedolizumab biosimilar candidate to Entyvio

The second vedolizumab biosimilar candidate is now under review by the US FDA. On July 31, Fresenius Kabi announced that its 351(k) application was accepted by both the FDA and the EMA for PB016, a proposed vedolizumab biosimilar candidate to Entyvio lyophilized vial for intravenous administration.

PB016, in-licensed from Polpharma Biologics S.A., is a proposed biosimilar to IV vedolizumab, an integrin-receptor antagonist indicated for the treatment of adults with moderately to severely active ulcerative colitis and Crohn’s disease in adults.

vedolizumab biosimilar

“FDA and EMA acceptances for review of IV vedolizumab biosimilar marks important milestones in the development program and underscores our commitment to improving patient access to high-quality, affordable biologic medicines,” said Dr. Sang-Jin Pak, President Biopharma at Fresenius Kabi. “With IV vedolizumab, we are advancing our autoimmune biosimilars portfolio and taking another step toward providing additional treatment options for patients living with chronic inflammatory diseases.”

The first biosimilar biologic licensing application was submitted in June by Alvotech and Teva.

In Other Biosimilar News

Amneal closed on its purchase of Kashiv Biosciences, a deal which “combines Kashiv’s biologics research, development and manufacturing capabilities with Amneal’s commercial scale, establishing biosimilars as a major long-term growth pillar within the Company’s Affordable Medicines business.” 

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA. 

Tracking Two Bills to Remove the Clinical Efficacy Study Requirement for Biosimilar Development

Proposals in the House and Senate, both titled the Expedited Access to Biosimilars Act, may officially remove the FDA’s requirement for clinical efficacy studies for biosimilar candidates.

On July 15th, a new bipartisan bill was introduced into the House of Representatives that would expand access to biosimilars by modernizing the FDA’s biosimilar approval process. This could be paired with a similar proposal just reaching Senate Committee discussion. Both of these proposals seek to reduce the cost of biosimilar development through squeezing out the need for comparative efficacy studies.

Expedited Access to Biosimilars Act

As reported earlier, the FDA in October 2025 announced a draft guidance that would achieve the same end, to remove the mandate for late-stage clinical efficacy trials for biosimilar manufacturers. However, a final guidance has not yet been released.

Introduced by Representatives Nick Langworthy (R-NY) and Kim Schrier, MD (D-WA), the Expedited Access to Biosimilars Act (HR 9661) could codify long-awaited regulatory changes to comparative trial expectations in the 351(k) biosimilar pathway.

According to a press release from Congressman Langworthy’s office, the act would eliminate unnecessary regulatory hurdles while preserving the FDA’s authority to require additional studies whenever scientifically warranted. This supports the October 2025 announcement of a draft guidance for removal of a mandate for phase 3 clinical efficacy studies for biosimilars. A key stipulation of the proposal would be a requirement for FDA to notify manufacturers early in the review process if additional late-stage comparative efficacy studies will be required. The aim would be to provide greater certainty around the clinical trial resources required for a successful biosimilar application process as well as avoiding unnecessary delays in the application process.

A number of associations have express support for the legislation including the Association for Accessible Medicines, the American Society of Health-System Pharmacists, and America’s Health Insurance Plans, among others.

The Senate’s 2025 Proposal

A Senate proposal by the same name (S.1414), introduced in April 2025 by Senator Rand Paul (R-KY), seeks largely the same goals. It has languished in the Committee on Health, Education, Labor, and Pensions, without additional cosponsors, until now. A committee meeting is scheduled for July 22 to finally consider this legislative proposal. It has one co-sponsor (Sen. Mike Lee, R-UT).

We’ll be monitoring whether the Expedited Access to Biosimilars Act can break through for an eventual debate and vote on either the House or Senate floor.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA.

Biosimilar Bytes: Golimumab Patent Litigation, Positive Keytruda Biosimilar Trial Results

Janssen files BPCIA patent suit against an impending Alvotech golimumab biosimilar, and Samsung Bioepis releases positive phase 3 trial results

Golimumab Patent Battle for Alvotech and Bio-Thera Biosimilars

Alleging patent infringement, Janssen Biotech filed BPCIA litigation in US District Court for the Eastern District of Virginia against Alvotech involving AVT05, its golimumab biosimilar candidates. According to Janssen, 14 patents each are at issue on its reference products Simponi and Simponi Aria.

Janssen BIotech v Alvotech patent litigation

Alvotech and its commercialization partner Teva resubmitted its 351(k) application for approval of ATV05 on June 4. It is not known why Janssen did not file the BPCIA patent suit once Alvotech first sent its biologic licensing application to the FDA in January 2025.

Bio-Thera Solutions and its marketing partner Accord BioPharm received the first FDA approval for golimumab biosimilars on May 15, 2026. Of course, they are also in the midst of patent litigation with Janssen to prevent a delay in marketing of this biosimilar as well. Janssen first filed its complaint in March 2026, involving 17 patents. In response, Bio-Thera filed for Inter Partes Review on 4 patents involving methods of treatment, while claiming the others were either obvious or publicly available. According to Big Molecule Watch, a District Court hearing is scheduled for September 1. The principal patents on Simponi have already expired. Accord BioPharm had previously announced an expected launch later this year.

Samsung Bioepis’ SB27 Phase 3 Results

Despite several other prospective pembrolizumab biosimilar makers foregoing or discontinuing phase 3 trials, Samsung Bioepis has plowed forward, announcing preliminary positive results for its investigational product SB27.

Although the phase 1 and phase 3 trials are not yet completed, the initial results announced indicated equivalent pharmacokinetic data for SB27 compared with the reference product Keytruda, as well as clinically similar outcomes (i.e., objective response rates) in the double-blind, parallel-group, phase 3 investigation at week 24.

The FDA announced last October that late-stage clinical trials will no longer be routinely required for biosimilar development and approval. Most manufacturers pulled the plug on ongoing or planned trials for pembrolizumab biosimilars, as we reported in November.

Samsung reported that it expects to complete both the phase 1 and phase 3 trials by the end of 2026.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated biosimilar approval database.

When is a Biosimilar a Biosimilar?

In 2026, is the definition of a biosimilar the same for countries’ drug regulatory systems around the globe? A recently published scoping survey attempted to answer the question.

Although there has been a decade of interest in moving towards global biosimilar regulatory standards, we first must answer a more foundational question: Is the definition of a biosimilar the same worldwide?

You may suspect that the answer is obvious, but then again, why are we asking it? Is it a trick question? Years ago, the answer was not so simple. Those of us covering the biosimilar field in the 2010s will recall that some Indian companies, for example, were producing what might be considered “follow-on” medicines by the FDA’s regulatory standards, but were promoting them as biosimilars.

No Guidances by FDA on Follow-on vs. Biosimilar Products

Global biosimilar regulation

The FDA’s own regulatory definition was not set in stone: Basaglar, the second insulin glargine product to receive FDA approval, is a biosimilar but technically not a biosimilar. Even today, there may be some confusion as to whether Basaglar is considered a biosimilar or a follow-on product. It was indeed approved by the FDA under a 505(b)2 application, principally because insulins were not considered eligible for the 351(k) approval pathway until 2020. The FDA would probably support that it is clinically equivalent to Lantus in any way that matters. Yet, from a regulatory perspective, it was not evaluated as part of the biosimilar pathway, so it cannot be designated a biosimilar.

The same can be said for Granix, the second filgrastim product approved by the FDA, which underwent its approval process before the 351(k) was implemented (and under which Zarxio was licensed). It is important to note that the FDA itself has not tried to improve clarity by announcing retrospectively that these agents can be considered either biosimilar or an equivalent.

A Survey of Biosimilar Definitions

So, is a biosimilar a biosimilar throughout the world? An article published in JAMA Health Forum described a survey of 19 countries’ biosimilar regulatory guidelines. These included 12 with emerging and developing economies and 7 with advanced economies, according to the World Health Organization classification. The authors, from the University of San Francisco and GlaxoSmithKline, found that most countries define “biosimilarity as the absence of differences in the medicine’s quality, safety, and efficacy compared with the RP. Sixteen countries explicitly required comparability exercises to demonstrate biosimilarity, and 13 countries specified that the same RP must be used in these studies.

“Of the 19 countries in the study sample, 17 (89%) have adopted the WHO’s biosimilar terminology; the exceptions were Indonesia, which uses the term follow-on biological in addition to biosimilar, and Tanzania, which uses the term similar biotherapeutic product. A total of 17 countries (89%; except India and South Korea) define biosimilarity according to the absence of differences in quality, safety, and efficacy between the biosimilar and the reference product, although in some countries (Egypt, Turkey, UK, and US), this is heavily implied rather than explicitly stated. Most countries (n = 16 [84%]) require comparability exercises (by definition), but 3 (Mexico, Indonesia, and China) do not explicitly include this requirement.”

The authors also stated that all advanced economies waived the need for clinical efficacy and immunogenicity testing when justifiable, but guidelines from emerging and developing economies differed on clinical study waivers.”

Interestingly, one of the areas of least consensus is that of biosimilar naming and labeling guidance provided. Countries such as France, Germany, Japan, and South Korea do not specify any requirements, whereas the UK, US, and Canada do, among the WHO advanced economic sector. Among countries in the emerging and developing economic region, China and Mexico do have naming and labeling guidelines, whereas Brazil, India, and Indonesia do not. The area of greatest agreement seemed to be in acceptance of extrapolation, with all but Saudi Arabia among the surveyed countries with published extrapolation guidelines.

Scoping surveys such as this are necessary steps in a march towards global regulatory standards for biosimilars. They show not only how far we’ve come in reaching basic agreements, but also how far we need to go. Perhaps, most importantly, they show us areas where a push for global standards would have the least likelihood of success.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated biosimilar approval database.

Alvotech Submits First Entyvio Biosimilar Application to FDA

The first 351(k) application for a vedolizumab (Entyvio) biosimilar has been submitted by Alvotech. If approved, the biosimilar would be marketed by Teva. Alvotech also resubmitted biosimilar applications for golimumab and aflibercept.

On June 8, Alvotech announced that the FDA has accepted its biologic licensing application for AVT16, a biosimilar candidate for the reference drug Entyvio. This marks the first FDA 351(k) drug application for a vedolizumab biosimilar.

vedolizumab biosimilar, Entyvio biosimilar

In its press release, Joseph McClellan, Chief Operating Officer  of Alvotech, stated, “FDA acceptance of the BLA for AVT16 is another important step in advancing our mission to increase access to biologic medicines for patients worldwide. Our proposed interchangeable biosimilar to Entyvio builds on our experience in immunology and reflects the strength of our fully integrated development and manufacturing platform.”

Vedolizumab, an integrin-receptor antagonist, is currently approved to treat adults with moderate-to-severe ulcerative colitis and Crohn’s disease. The reference product is available in both intravenous infusion and subcutaneous injections.

Takeda’s US Entyvio net revenues were over $4 billion in 2024, but the biologic has been targeted for Medicare maximum fair price negotiation. The negotiated price will be implemented on January 1, 2028, unless biosimilar launch is imminent. The original drug patent is set to expire in 2026.

Intravenous Infusion vs. Subcutaneous Injection

AVT16 would be available only as an intravenous infusion. Alvotech’s biologic licensing application does not cover the subcutaneous injectable. A separate investigational product, AVT80, promises a biosimilar version of the prefilled syringe and autoinjector administration. Alvotech noted that the European Medicines Agency has received a marketing application for both AVT16 and AVT80. It is not clear whether Alvotech and its marketing partner Teva, intends to market these products under separate brand names if approved. The patent on the subcutaneous formulation may not expire until the 2030s, according to some sources, which may play into Alvotech’s decision to separate the FDA applications.

In Other Alvotech Biosimilar News  

In November 2025, Alvotech received complete response letters from the FDA on two products—its biosimilar versions of golimumab and aflibercept. On June 4, 2026, the biosimilar manufacturer revealed that it had resubmitted its 351(k) applications to the FDA for both products (AVT05 for golimumab and AVT06 for aflibercept). Alvotech noted that it expects an FDA decision within 6 months. The complete response letters cited production facility issues, and not data or clinical quality questions. The latest FDA surveillance inspection of the Reykjavik production facility was completed by May 11, according to the company.  

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated biosimilar approval database.

The Effect of MFP on Enbrel Sales, and Biosimilar Implications

In reporting its 2026 first-quarter earnings, Amgen indicated a 37% reduction in Enbrel sales revenue compared with the first quarter of 2025. Was this related directly to the January 1 implementation of the MFP price for Enbrel or just a continuing trend in its sales? What does it mean for the etanercept biosimilars?

On January 1, 2026, Medicare-negotiated prices for the first set of targeted drugs went into effect. Among these products was Enbrel (etanercept), the only drug on this list with impending biosimilar competition. Although biosimilar competition in this category will not be introduced until 2028, the maximum fair price (MFP) program will threaten manufacturers of etanercept biosimilars as well as other biosimilar makers.

Amgen Continues to See Enbrel Sales Decline

In reporting its 2026 first-quarter earnings, Amgen indicated a 37% drop in Enbrel sales revenue compared with the first quarter of 2025. In its press release, Amgen stated, “The decline in net selling price reflects the impact of US Medicare part D price setting under the Inflation Reduction Act…as well as increased 340B program mix.” We assume that this also considers increased catastrophic benefit liability for the manufacturer owing to part D redesign.

Enbrel sales revenues

None of this is surprising: Amgen has reported lower net sales revenues for Enbrel every year since 2020. Nearly all of its Enbrel sales revenue is US-based. Three etanercept biosimilars have been sold in Europe for more than 6 years, and Pfizer holds commercial rights to Enbrel outside of North America. It reported Enbrel sales revenues of $627 million in 2025, which is also 9% lower than in 2024).

This continuing downward trend in the US is likely the result of several factors: (1) heavy competition from other branded anti-TNF agents and interleukins, (2) lower-priced biosimilar competition in the adalimumab and ustekinumab categories, (3) the recently implemented MFP pricing, and (4) other market factors (e.g., 340B mix of sales, part D redesign).

The MFP Effect: A 67% Discount on Enbrel and What It Means Down the Road for Biosimilar Makers

The lower MFP price for Enbrel, which is 67% below the previous WAC price, does result in lower net selling price for Amgen and thus lower revenues. We just don’t know how much it contributed to Enbrel’s first-quarter sales decline.

Overall, this spells worrisome news for the two currently approved etanercept biosimilars (by Samsung Bioepis and Sandoz). It likely means that whatever market shares the biosimilar manufacturers can attain when they do launch, it will be worth significantly less in total revenue dollars than they initially anticipated. If we extrapolate the sales figures from the first quarter to the full year, total 2026 US revenue for Enbrel will be approximately $1.3 billion. Based on continuing revenue declines (not necessarily from prescription volume declines), this figure can easily dip below the $1 billion mark (i.e., the definition of a blockbuster drug) by the end of the year.

Because of the multiple factors affecting Amgen’s Enbrel earnings, it may not provide the best evidence to support biosimilar manufacturers’ fears about the Inflation Reduction Act, reported earlier. Yet it does make sense that the MFP will lower sales expectations for biologics that were (or are) considered targets for biosimilar competition. This will make the decision to spend R&D resources on those prospective biosimilars less enticing.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA.

Will We Remember Marty Makary in 2030?

For the biosimilar industry, serious progress was made in streamlining biosimilar development, but little was finalized, under the leadership of now-former FDA Commissioner Dr. Marty Makary.

With the resignation on May 12th of Marty Makary, MD, MPH, as FDA Commissioner, it is difficult to analyze his performance after a scant 13 months in office. For instance, the FDA suffered massive staff cuts under the auspices of Elon Musk’s DOGE and was forced to hire back many of the same people.

FDA Commissioner Marty Makary
Former FDA Commissioner Dr. Marty Makary

Meetings of FDA’s Advisory Committees have been few and far between. This essentially wiped out the public’s ability to comment directly to scientists at the time of their votes for recommending or denying a particular drug approval. In fact, several of the FDA Advisory Committees no longer meet at all; only four meetings were scheduled to occur this year through the end of this month.

A Legacy of Advancing Biosimilar Development?

The FDA under Dr. Makary seemed eager to move forward to streamline biosimilar development, but this has not yet resulted in finalized regulatory policy. It is true that under his watch, the FDA issued its draft guidance on the removal of the mandate for phase 3 trials in biosimilar development, but 7 months later, no finalized guidance has been issued. During this time, the FDA has seemingly implemented this rule in any case, and as reported earlier in 2026, several biosimilar manufacturers have acted upon it, by terminating active phase 3 investigations.

In addition, we still have no official policy that nullifies or overrides the infamous interchangeability designation, despite FDA’s expressed opinion that it should be applied to any approved biosimilar, and holding a workshop on the issue last September.

In March, a draft guidance was released on removing the need for bridging studies when non-US licensed reference products are used for pharmacokinetic studies. The timing of the finalized document (after a public comment period) is up in the air, and may be further delayed without an official FDA Commissioner in office.

At certain points, he seemed to embrace the chaos at HHS and at others he tried to tamp down fires caused by the administration. In the end, his decision to fight industry interests in their promotion of flavored E-cigarettes may have been his undoing. However, it seems unlikely that anyone can truly make a lasting impression at FDA after only 13 months.

Overall, a statement he made at last October’s GRx+Biosims meeting sums up his legacy: “I think that we can unite in this country by focusing around health.” It demonstrated either the impossible challenge he faced in the administration or extreme obliviousness regarding the serious attacks on US public health by his boss at Health and Human Services.

This article was written by our Director of Content, Stanton Mehr. Stan has been writing commentary and reporting news about the biosimilar industry since the submission of the first biosimilar 351(k) application to the FDA 13 years ago. Since that time, BR&R has been tracking the US biosimilar marketplace, with the industry’s original, comprehensive and updated database of biosimilar filings with the FDA.