Skylar Jeremias is the Managing Editor for The Center for Biosimilars and The American Journal of Managed Care (AJMC).

Skylar Jeremias

The FDA has issued draft guidance that stakeholders say could significantly accelerate the entry of biosimilars into the US market, potentially unlocking substantial cost savings for the health care system.

Scientific Considerations in Demonstrating Biosimilarity to a Reference Product: Updated Recommendations for Assessing the Need for Comparative Efficacy Studies

," outlines updated criteria for when a comparative efficacy study (CES) may not be necessary for a biologics license application (BLA) submitted under section 351(k) of the Public Health Service Act. This update supersedes the agency’s 2015 guidance and reflects its evolving scientific approach to biosimilar evaluation.

By prioritizing analytical studies, the FDA aims to reduce both the time and cost of biosimilar development. | Image credit: Postmodern Studio - stock.adobe.com

Shifting From Clinical Trials to Analytical Science

Historically, biosimilar development has been slowed by complex, costly 

. CESs, in particular, have represented a significant bottleneck—both financially and logistically.

The FDA’s draft guidance emphasizes that advanced analytical technologies can now detect minor differences between highly purified proteins more precisely than clinical trials.

 A well-conducted comparative analytical assessment (CAA) is often more sensitive than a CES, whose outcomes may be affected by factors such as dose selection, patient population variability, or trial design.

Under the new framework, a CES may be waived if:

The biosimilar and reference product are highly purified, derived from clonal cell lines, and analytically well characterized

Key quality attributes of the reference product are well understood and measurable via CAA

A human pharmacokinetic (PK) similarity study is feasible and clinically meaningful

By prioritizing analytical studies over routine CESs, the FDA aims to reduce both the time and cost of biosimilar development—potentially trimming expenses estimated between $100 million and $300 million per program and shortening development timelines by several years.

Policy Leaders Highlight Potential Savings

The draft guidance has drawn praise from policy makers and industry advocates. 

 described previous regulatory requirements as burdened by “sky-high costs [and] endless red tape,” stating that the guidance replaces “bureaucracy with science, monopolies with competition, and despair with hope.”

FDA Commissioner Marty Makary, MD, emphasized that removing unnecessary barriers could expand competition, lower biologic prices, and improve patient access. Similarly, 

 called the guidance “momentous” in addressing the US prescription drug affordability crisis.

 Executive Director Juliana M. Reed noted, “Now more than ever, it is clear that biosimilars—

safe, effective, and lower-cost medicines that reference biologics

—are key to fixing America’s healthcare affordability crisis. 

 say they have not taken their medication as prescribed due to unaffordable prices. Today’s updated guidance from the FDA and Commissioner Makary on biosimilars is a momentous, critical step in unlocking the potential of these modern treatments to lower prescription drug prices for all Americans.”

Reed also highlighted that biosimilars have already generated over $56 billion in US savings and that the new framework could unlock an additional $181 billion over the next 5 years.

Robert F. Kennedy Jr (left), Marky Markary, MD (center), and Mehmet Oz, MD (right), at the press conference announcing the new biosimilar guidance.

At the press conference announcing the draft guidance, the policy makers repeatedly emphasized that all biosimilars should be considered interchangeable with their reference products.

 They suggested this designation would allow pharmacists to automatically substitute biosimilars and encouraged state governors to actively promote biosimilar use, framing interchangeability as a key tool to expand access and reduce costs.

The officials did acknowledge that some states require notification to patients or providers when a biosimilar substitution occurs. However, they did not address portions of the country that maintain total bans on substitution, nor clarify whether these laws would be considered void under the new federal guidance. As 

previously reported by The Center for Biosimilars

, 4 states and Puerto Rico currently prohibit automatic biosimilar substitution, requiring prescriptions to explicitly name the biosimilar.

 Without federal preemption or updated state legislation, it remains uncertain how these restrictions would interact with the federal guidance, creating ambiguity about the practical effect of the press conference claims.

Previously, a biosimilar can carry the FDA’s interchangeability designation only if the manufacturer requests it and provides additional evidence demonstrating that the biosimilar produces the same clinical result as the reference product in any given patient, and that switching between the products poses no additional risk. Additionally, interchangeability typically applies only to pharmacy-dispensed biologics, typically self-administered therapies such as adalimumab or insulin in which a provider is not present for the substituion. Laws around interchangeability have never restricted access to 

, meaning patients receiving clinic-based therapies—including many oncology treatments—continue to access biosimilars regardless of interchangeability status.

Thus, while the statements from Kennedy, Makary, and Oz conveyed strong political support for biosimilars, they may overstate the immediate practical impact, particularly in jurisdictions with restrictive substitution laws or total bans, or for patients receiving clinic-administered biologics.

Despite regulatory momentum, the so-called biosimilar void remains a critical challenge. According to Samsung Bioepis, 118 biologics representing nearly $232 billion in US sales are expected to lose patent protection between 2025 and 2034, yet only about 10% of these have biosimilars in active development.

Limited return on investment for niche or rare-disease products:

 Manufacturers hesitate to invest heavily in biosimilars for small patient populations

 Advanced biologics—such as bispecific antibodies or cell-based therapies—require specialized facilities and expertise

 Even with streamlined guidance, bringing a biosimilar to market can take nearly a decade

Market uncertainty under the Inflation Reduction Act:

 have created new disincentives for some biosimilars, particularly those approaching Medicare negotiation windows.

Without additional reforms—such as addressing rebate structures, patent thickets, prescriber incentives, biosimilar education gaps, and pharmacy benefit manager transparency—the US may not realize the full potential of biosimilar competition.

Additionally, many biosimilars are developed by international companies that have licensing and commercialization agreements with larger American-based companies. With the Trump administration's previous statements about potentially placing 

tariffs on international pharmaceutical products

 and initiatives to bring more pharmaceutical manufacturing into the US, it's uncertain if there will be unintended interactions between policies that may create new barriers to bringing biosimilars to market.

Implications for Managed Care and Patient Access

For managed care executives, payers, and provider systems, the FDA’s draft guidance represents a critical step toward faster, more cost-effective biosimilar entry. However, the benefits of these reforms could take years to materialize, underscoring that policy change alone will not close the biosimilar void.

They encouraged patients to “ask their doctors about biosimilars,” a call that highlights a disconnect between perception and reality. For many therapeutic areas, 

; for others—particularly in oncology—biosimilars are so widely adopted that patients may already be receiving them without realizing it.

 As a result, the immediate public impact of this guidance is likely to be modest, even as it lays the groundwork for long-term gains in affordability and access.

If development efficiencies are not paired with improved commercial viability, many biologics will continue to struggle to gain market uptake, and potential cost savings will remain unrealized. Stakeholders must now look beyond regulatory reform to focus on aligning incentives, ensuring manufacturing capacity, and reinforcing provider and patient education to build lasting confidence in biosimilars.

Scientific considerations in demonstrating biosimilarity to a reference product: updated recommendations for assessing the need for comparative efficacy studies. FDA. October 29, 2025. Accessed October 29, 2025. 

https://www.fda.gov/regulatory-information/search-fda-guidance-documents/scientific-considerations-demonstrating-biosimilarity-reference-product-updated-recommendations

Niazi SK. BioRationality: the FDA sets sights on removing clinical efficacy studies for biosimilars. The Center for Biosimilars

. October 29, 2025. Accessed October 29, 2025. 

https://www.centerforbiosimilars.com/view/biorationality-the-fda-sets-sights-on-removing-clinical-efficacy-studies-for-biosimilars

Biosimilars reform. FDA. October 29, 2025. Accessed October 29, 2025. 

https://www.hhs.gov/live/live-1/index.html#12163 

Biosimilars Forum applauds FDA and Commissioner Dr. Marty Makary for supporting safe, effective and lower-cost biosimilars. The Biosimilars Forum. October 29, 2025. Accessed October 29, 2025. 

https://biosimilarsforum.org/2025/10/29/biosimilars-forum-applauds-fda-and-commissioner-dr-marty-makary-for-supporting-safe-effective-and-lower-cost-biosimilars/

Jeremias S. The biosimilar void: 90% of biologics coming off patent will lack biosimilars. The Center for Biosimilars. February 5, 2025. Accessed October 29, 2025. 

https://www.centerforbiosimilars.com/view/the-biosimilar-void-90-of-biologics-coming-off-patent-will-lack-biosimilars

Jeremias S. The age of adalimumab is upon us: how stakeholders can prepare. The Center for Biosimilars. June 28, 2023. Accessed October 29, 2025. 

https://www.centerforbiosimilars.com/view/the-age-of-adalimumab-is-upon-us-how-stakeholders-can-prepare

Jeremias S. The Trump administration’s drug price actions and why US prices are already sky-high. The Center for Biosimilars. May 17, 2025. Accessed October 29, 2025. 

https://www.centerforbiosimilars.com/view/the-trump-administration-s-drug-price-actions-and-why-us-prices-are-already-sky-high

Trump delaying triple-digit pharma tariffs to negotiate drug price deals. Politico. October 1, 2025. Accessed October 29, 2025. 

https://www.politico.com/news/2025/10/01/trump-delays-triple-digit-pharma-tariffs-to-negotiate-drug-price-deals-00590051

Santoro C. Biosimilar uptake lags in US despite potential cost savings. 

. August 16, 2024. Accessed October 29, 2025. 

https://www.ajmc.com/view/biosimilar-uptake-lags-in-us-despite-potential-cost-savings

Articles

FDA's new guidance streamlines biosimilar development, reducing costs and regulatory hurdles and potentially enhancing market access and affordability.

A Closer Look at New FDA Guidance Removing Barriers to Biosimilar Development

Biosimilars possess the potential to drastically enhance patient access and ensure long-term sustainability for regional health systems across Latin America and the Caribbean (LAC), according to a new narrative review 

. The analysis, conducted by María Herrán, MS, and Juan-Manuel Anaya, MD, focused on the transformative role of biosimilars in high-cost therapeutic areas like oncology and chronic autoimmune diseases.

Biosimilars revolutionize health care access in Latin America, offering cost savings and improved treatment availability for chronic conditions and oncology. | Image credit: C Malambo:peopleimages.com - stock.adobe.com

The authors conducted the review to address a persistent and costly challenge facing healthcare providers and payers across the low- and middle-income regions of LAC: the prohibitive expense of original biologic therapies. While these advanced treatments have revolutionized care for people with complex and chronic conditions, their high price tags have significantly limited their widespread availability, creating deep disparities in treatment access.

The study underscored that, as cost-effective alternatives, biosimilars offered a powerful mechanism to shift this paradigm. The central objective of the analysis was to map the full spectrum of economic benefits—beyond simple cost savings—that biosimilars could bring to fragmented and often financially constrained public and private health systems throughout the region.

Herrán and Anaya's review identified four primary economic levers activated by biosimilar introduction: cost reduction, access expansion, market competition, and relief of financial pressure. The authors concluded that the cumulative impact of these factors positioned biosimilars as an essential tool for fiscal stability and public health improvement.

Specifically, the analysis concluded that the introduction of biosimilars has the potential to:

 By entering the market at a lower price point than reference products, biosimilars provided immediate opportunities for payers to achieve significant budget savings.

 The lower per-unit cost made previously unattainable biologic treatments accessible to a greater number of people across all socioeconomic segments.

 The presence of multiple biosimilar products targeting the same reference biologic was found to foster healthy competition, which drove down overall drug expenditures.

 By generating savings, biosimilars allowed health systems to reallocate funds, thereby reducing the heavy financial burden placed on public sector budgets and freeing capital for other essential services.

The authors projected that the biosimilars industry in LAC was poised for accelerated growth, anticipating a major shift driven by enhanced regional regulations, evolving market dynamics, increased investment, and a greater emphasis on stakeholder education. They argued that cultivating a robust biosimilar sector was key to improving overall health care resiliency and economic stability throughout the region.

"We found that the successful adoption of biosimilars is not merely about saving money in the short term, but is fundamentally an issue of health equity and long-term economic stability for the entire health system," the authors noted in the published review.

Patient Demographics and Study Limitations

While the review’s focus was macro-level economics and health system impact, the authors centered their findings on improved care for 

people with complex and chronic conditions

, including those with cancer and autoimmune diseases. Since this was a 

 that synthesized existing literature and economic models, it did not include new primary data or specific, quantified patient demographics from a single cohort study. The review instead provided a high-level framework of economic outcomes impacting the general population receiving specialized biologic care in the LAC region.

The authors were careful to contextualize their findings within the current environment. A recognized limitation inherent to this analysis was the highly variable and fragmented regulatory and market landscape across different LAC countries. The potential for accelerated growth, as mapped in the review, was contingent upon the successful implementation of the necessary regulatory enhancements and education initiatives required to address existing market inconsistencies and foster trust among prescribers and patients. Without regulatory alignment and continued investment, the full projected economic benefits would not be realized.

Ultimately, Herrán and Anaya concluded that the strategic integration of biosimilars represented a pivotal opportunity for payers and policymakers to transform access to high-quality care for individuals in the LAC region.

Herrán M, Anaya J-M. Mapping economic outcomes: how biosimilars enhance access to health systems in Latin America and the Caribbean. 

. 2025:96:102606. doi:10.1016/j.coi.2025.102606

Biosimilars revolutionize health care access in Latin America, offering cost savings and improved treatment availability for chronic conditions and oncology.

Biosimilars Improve Health System Resilience in Latin American, Caribbean Nations

A proposed insulin glargine biosimilar (Basalin) demonstrated comparable efficacy, safety, and immunogenicity to the originator product (Lantus) in adults living with type 2 diabetes, according to results from a global phase 3 equivalence trial. The findings support the regulatory path for biosimilar long-acting insulins, which are essential products for driving price competition and generating cost savings within managed care formularies.

Type 2 diabetes. | Image Credit: MQ-Illustrations - stock.adobe.com .jpeg

The decision to conduct this robust comparative trial was rooted in the persistent challenge of high insulin costs in the US and globally. Insulin glargine, a cornerstone of basal insulin therapy, is one of the most widely used and expensive biologics. While follow-on insulins have entered the market, the need for fully approved biosimilars—products shown to be highly similar to the reference product with no clinically meaningful differences—remains paramount for driving price competition.

This phase 3, multicenter, open-label, equivalence trial sought to definitively establish that the proposed biosimilar could produce the same clinical results as the originator product in people with type 2 diabetes. Demonstrating equivalence across primary and secondary endpoints is the essential regulatory step required to facilitate broader adoption and support interchangeable designation, which would allow pharmacy-level substitution and streamline access for health plan members.

Investigators enrolled 567 adult participants who had a diagnosis of type 2 diabetes and were seen at 57 sites. Participants were randomized in a 1:1 ratio to receive either the reference insulin glargine product or the biosimilar product in combination with their existing oral antidiabetic medications. Insulin dosing was individually adjusted according to metabolic status and predefined glycemic targets.

The participant cohort was representative of a typical type 2 diabetes population, with a mean age of 60.8 years and a mean body weight of 98.1 kg. The majority of participants were male (60.1%) and identified as White (79.7%). Demographic characteristics, including baseline mean hemoglobin A1c (HbA1c) levels, were comparable between the two treatment groups, ensuring a reliable comparison of outcomes. A total of 515 participants (90.8%) completed the 26-week study period.

The investigators successfully met the study's primary efficacy endpoint, confirming equivalence between the biosimilar and the originator product based on the change in glycated hemoglobin (HbA1c) levels from baseline to week 26. The least-squares mean difference in HbA1c change fell well within the predefined equivalence margin, definitively demonstrating that the biosimilar provided comparable, effective glycemic control.

Furthermore, the safety profile of the biosimilar mirrored that of the reference product. The frequency and nature of treatment-emergent adverse events (AEs) were consistent with established safety profiles for insulin glargine. Hypoglycemia, the most commonly reported AE, affected approximately half of the participants in both groups, showing no clinically meaningful difference. Crucially, in terms of immunogenicity, the trial observed similar proportions of participants who tested positive for treatment-induced anti-insulin antibodies (AIA) in both the biosimilar (19.2%) and reference (21.3%) groups, indicating that the biosimilar did not prompt a differential immune response compared to the originator.

Despite the robust design, the trial had several limitations inherent to phase 3 studies. First, the open-label design, where both participants and investigators knew the assigned treatment, could introduce potential bias, although primary endpoints were objectively measured. Second, the study period was limited to 26 weeks; longer-term follow-up data is necessary to fully assess the continued long-term safety and immunogenicity of the biosimilar. 

Finally, the majority of the cohort was White, which may limit the generalizability of the findings across more diverse ethnic populations living with type 2 diabetes. Future research should prioritize real-world evidence and studies focused on patient-reported outcomes to complement the clinical trial data.

The authors commented on the broader impact of the findings. They wrote, "The emergence of biosimilar insulins offers a prospective path to reduce the overall economic burden of diabetes management while maintaining the highest standard of patient care."

Gisondi P, Bellinato F, Curic T, Gironlomoni G. Biosimilars for the treatment of moderate to severe chronic plaque psoriasis. 

. 2025;15:401-410. doi:10.2147/PTT.S510156

Comparable Insulin Glargine Biosimilar Could Help Relieve Diabetes Costs

Biosimilar ranibizumab (Razumab) is clinically equivalent to its innovator counterpart (Lucentis/Accentrix) for treating myopic choroidal neovascular membrane (mCNVM), a leading cause of vision impairment in younger adults, according to compelling evidence from a new multicenter, real-world study.

, offer crucial support for payer adoption of biosimilars as cost-effective, high-quality alternatives, particularly in resource-constrained healthcare systems.

Rationale: Addressing the Real-World Evidence Gap

The BRIM Study was conducted to compare the efficacy and safety of the 2 molecules in a real-world setting. While biosimilars are approved based on high similarity to their reference products, head-to-head comparative data for specific, less-common indications like mCNVM often remain scarce.

"In recent years, biosimilar versions of ranibizumab have emerged as more affordable therapeutic alternatives, particularly in low- and middle-income countries," the study authors noted. However, the researchers emphasized that despite increasing use, comparative data in this specific patient population was lacking. The research aimed to "provide evidence that may guide treatment decisions and inform healthcare policy in regions where cost remains a significant barrier to the use of anti-VEGF therapy."

This retrospective, multicenter study included 80 eyes of treatment-naïve patients with mCNVM who were followed for a minimum of 12 months. Patients were divided into 2 cohorts: 38 eyes received innovator ranibizumab (Group A), and 42 eyes received biosimilar ranibizumab (Group B). The treatment regimen for both groups followed a flexible, pro re nata protocol guided by disease activity observed on optical coherence tomography.

The included participants were adults, with the mean (SD) age of patients in the innovator group being 41.21 (7.33) years and the mean age of patients in the biosimilar group being 42.32 (3.92) years. The groups were well-matched in terms of demographics, with the mean refractive error being highly myopic in both cohorts (innovator, –10.33 [4.8] D; biosimilar, –11.11 [3.75] D).

The primary outcome was the change in best-corrected visual acuity (BCVA) at 12 months. The study demonstrated non-inferiority between the two treatment arms. Patients receiving innovator ranibizumab experienced an improvement in mean BCVA from 51.0 (16.5) ETDRS letters at baseline to 64.5 (5.5) letters at 12 months. Similarly, patients receiving biosimilar ranibizumab saw an improvement from 52.5 (16.5) letters to 64.5 (4.5) letters. The difference in visual acuity between the two groups was not statistically significant (

> .05). Anatomical outcomes, measured by central macular thickness (CMT), also showed similar reductions. 

In the innovator cohort, mean CMT decreased from 332.03 (39.22) µm to 268.32 (18.78) µm at 12 months, while the biosimilar cohort experienced a comparable reduction from 315.03 (44.20) µm to 271.12 (20.39) µm. This equivalence extended to the treatment burden: patients in the innovator group required a mean of 2.68 (0.51) µm injections over the year, compared to 2.71 (0.49) µm injections for the biosimilar group. This comparable injection frequency confirmed the similar durability and efficacy of both treatments under a PRN protocol. 

Furthermore, the safety profiles were equivalent, with both groups maintaining stable intraocular pressure over the 12-month period, and researchers reported that no serious ocular or systemic adverse events were noted in either group during the course of the study.

While the study is robust due to its multicenter, real-world design, the authors acknowledged a few limitations. Because the study was retrospective, long-term complications, such as the progression of chorioretinal atrophy or recurrence patterns, could not be fully assessed due to the relatively short 12-month follow-up period. Furthermore, the findings are specific to the mCNVM indication, and the authors cautioned that extrapolation to other retinal diseases should only be done when supported by dedicated data.

Chakraborty D, Sinha TK, Sinha S, et al. Biosimilar versus innovator ranibizumab in myopic CNVM: comparative real-world outcomes—the BRIM study. 

. 2025:19:3741-3747. doi:10.2147/OPTH.S549744

A new study confirms that biosimilar ranibizumab matches innovator Lucentis in treating myopic choroidal neovascular membrane, supporting cost-effective healthcare solutions.

Data Confirm Biosimilar Ranibizumab Non-Inferiority as Myopic CNVM Treatment

Approximately 1 in 5 patients with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA) in Turkey were prescribed biosimilars rather than originator biologics, according to a new retrospective analysis from Erciyes University in Kayseri.

, highlight how biosimilar use patterns remain modest overall but tend to increase in later treatment lines—offering insight into prescribing behavior in a country where biologics are fully reimbursed under national health insurance.

Researchers report that biosimilar use was not influenced by disease type but correlated with treatment sequence, shorter disease duration, and female sex. | Image credit: Zerophoto - stock.adobe.com

The study aimed to quantify biosimilar (BS) prescription rates and identify factors influencing clinicians’ decisions between biosimilars and reference biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs). Although biosimilars have been available in Turkey for a decade, data on their uptake in rheumatology practice have been limited.

“Our results indicate that disease duration, female sex, and the order of current therapy were the most important predictors of biosimilar prescription,” the authors wrote. “The use of biosimilars increased significantly as treatment lines progressed, reflecting both growing clinician familiarity and broader market availability.”

The investigators reviewed manual and electronic health records of 647 adults diagnosed with axSpA (n = 436) or RA (n = 211) who received at least 1 b/tsDMARD between May 1, 2023, and December 31, 2023. Patient inclusion required meeting the Assessment of SpondyloArthritis International Society or ACR/EULAR diagnostic criteria. Demographic, laboratory, and treatment-related data—including disease activity scores, duration of treatment, and medication sequence—were extracted.

Participants’ mean (SD) age was 48.1 (12.6) years, and 66% were women. All patients were insured through Turkey’s Social Security Institution, ensuring cost-free access to biologic and targeted synthetic therapies when clinically indicated. Available biosimilars during the study period included infliximab, etanercept, adalimumab, and rituximab, while a generic version of tofacitinib was also listed though not prescribed to any patient.

Across all patients, 21.2% received a biosimilar as their most recent b/tsDMARD prescription. Rates were similar between disease types—22.2% in axSpA and 19.0% in RA (

 = .337)—suggesting that diagnosis did not significantly influence biosimilar uptake.

Patients with RA tended to be older and had a longer median disease duration (13 years vs 7 years; 

 < .001) than those with axSpA. Comorbidities, including hypertension, osteoporosis, diabetes, and dyslipidemia, were also more common in the RA group (all 

 < .05). The total duration of all b/tsDMARD use was significantly longer among individuals with RA (6.3 years) than those with axSpA (3 years; 

Among all biologic users, tumor necrosis factor (TNF) inhibitors dominated prescribing patterns, representing 80.7% of current treatments. Adalimumab was most frequently used in axSpA, while etanercept predominated in RA. In contrast, Janus kinase inhibitors such as tofacitinib or baricitinib were prescribed primarily for RA (16.6% of RA patients vs 0.2% of axSpA patients; 

Biosimilar use increased substantially with each successive treatment line. Patients who had received 5 or more distinct b/tsDMARDs showed the highest biosimilar prescription rate (39.7%), compared with just over 20% among those treated with their first biologic. Logistic regression revealed that female sex (OR, 1.70; 95% CI, 1.06-2.75), shorter disease duration (OR, 0.96; 95% CI, 0.92-0.99), and later treatment order (OR, 3.51; 95% CI, 1.06-11.60 for fifth-line or later use) were independently associated with biosimilar preference.

Interestingly, biosimilar users demonstrated higher disease activity measures at the time of data collection, including C-reactive protein and erythrocyte sedimentation rate levels. However, the researchers cautioned that these findings likely reflected the initiation of new therapy rather than reduced biosimilar efficacy. The median treatment duration for patients on biosimilars was zero years, indicating that many had recently started therapy.

Turkey represents one of the largest and fastest-growing pharmaceutical markets in the region, with national reimbursement policies facilitating broad access to biologic therapies. However, despite full coverage, prescriber behavior continues to favor reference biologics in early treatment stages. The authors suggested that clinician familiarity, patient comfort, and timing of biosimilar availability likely play roles in these trends.

Biosimilars have been shown globally to deliver comparable efficacy and safety to their originator counterparts while generating cost savings that expand patient access. In Europe, biosimilars account for roughly 70% of the TNF inhibitor market share, compared with far lower proportions in emerging markets. The Turkish findings therefore mirror an early stage of biosimilar integration into routine rheumatology practice.

“The increase in biosimilar use with subsequent therapy lines may reflect both increased physician confidence and accumulated experience over time,” the authors stated. “Wider education and awareness efforts could help normalize biosimilar prescribing earlier in the treatment sequence.”

The authors acknowledged several limitations, including the retrospective single-center design, lack of follow-up data on drug survival or switching outcomes, and exclusion of rheumatic diseases other than RA and axSpA. In addition, no socioeconomic analysis was performed, although uniform insurance coverage minimized cost disparities.

Future multicenter and longitudinal studies could clarify national trends and evaluate how biosimilar adoption impacts clinical outcomes and health care spending. As biosimilar availability expands, continued monitoring of prescription behaviors may help guide policy strategies to optimize equitable, cost-effective access to advanced therapies for inflammatory rheumatic diseases.

Kaplan H, Cengiz G, Kara H, Cüce İ, Kirnap M, Çaliş M. Analysis of data on biosimilar prescription rates in rheumatology practice from a reference center in Turkey. 

. 2025;15(1):28853. doi:10.1038/s41598-025-14816-0

Iskit AB. Key concepts in biosimilar medicines: What physicians must know. 

. 2022;9(1):86-91. doi:10.14744/nci.2021.84669

Researchers report that biosimilar use was not influenced by disease type but correlated with treatment sequence, shorter disease duration, and female sex.

Later-Line Therapies Drive Biosimilar Prescriptions in Turkish Rheumatology Practices

Stivant, demonstrated similar efficacy and safety to the reference biologic Avastin (reference bevacizumab; Genentech) in treating prethreshold type 1 retinopathy of prematurity (ROP), according to a recent analysis.

A new study reveals Stivant, a bevacizumab biosimilar, matches Avastin in safety and efficacy for treating retinopathy of prematurity in infants. | Image credit: Photographee.eu - stock.adobe.com

, suggest that biosimilar anti-vascular endothelial growth factor (VEGF) therapies could provide a cost-effective and accessible treatment option for premature infants at risk of severe vision loss.

ROP remains a leading cause of childhood blindness, resulting from abnormal retinal blood vessel growth in premature infants, affecting about 31.9% of infants globally, with greater prevalence in lower- and middle-income nations.

 As neonatal survival improves worldwide, the burden of ROP continues to grow, underscoring the need for affordable, safe, and effective therapies.

 Although laser photocoagulation remains a standard intervention, it can cause peripheral visual field loss and other complications. Anti-VEGF agents such as bevacizumab have emerged as effective alternatives but may be cost-prohibitive in some settings, an issue that biosimilar options can help address.

Conducted at the Khatam Eye Hospital in Mashhad, Iran, the study aimed to evaluate the noninferiority, safety, and efficacy of Stivant compared with Avastin in premature infants with bilateral prethreshold type 1 ROP. Investigators used a nonrandomized contralateral-eye design, administering Stivant to one eye and Avastin to the other. Infants were followed weekly for 4 weeks and biweekly thereafter until complete retinal vascularization.

The primary endpoint was the number of eyes achieving full vascularization without rescue laser photocoagulation. Secondary endpoints included the time between injection and full vascularization and the occurrence of ocular complications such as inflammation or infection.

A total of 44 infants (88 eyes) were included in the study, comprising 20 males and 24 females. The mean (SD) gestational age at birth was 27.6 weeks (1.8 weeks; range, 24-32 weeks), and the mean birth weight was 1737.7 g (554.9 g; range, 760-2200 g). The average age at injection was 34.5 weeks, with follow-up continuing until a mean age of 60 weeks.

Both treatments produced comparable outcomes. Thirty-nine eyes (88.4%) in each group achieved complete retinal vascularization after a single intravitreal injection. Five infants (11.3%) in both groups required bilateral rescue laser photocoagulation because of persistent or worsening disease.

The mean time to full retinal vascularization was nearly identical—25.55 weeks for Stivant and 25.46 weeks for Avastin (

 = .59). Kaplan-Meier survival analysis also found no significant difference between groups (

 = .928). Regression of plus disease, a clinical marker of active ROP, occurred at equivalent rates, further supporting comparable efficacy.

No ocular or systemic adverse events—including endophthalmitis, uveitis, vasculitis, or retinal detachment—were reported. “Our results demonstrated that Stivant was noninferior to Avastin in terms of efficacy and safety in treating prethreshold type I ROP,” the authors wrote. “However, due to the small sample size and pilot design, a definitive conclusion requires larger randomized studies.”

Bevacizumab has been a cornerstone in ROP management since the BEAT-ROP trial established its ability to prevent disease progression while sparing the peripheral retina. The introduction of biosimilar formulations may expand access to this therapy, particularly in regions where biologic cost is a barrier to care.

Stivant, the first bevacizumab biosimilar manufactured in Iran, has already been studied for systemic malignancies and retinal conditions such as diabetic macular edema, retinal vein occlusion, and neovascular age-related macular degeneration. Early evidence from animal models and small clinical case series supported its ophthalmic safety profile, paving the way for pediatric evaluation in ROP.

Investigators acknowledged several limitations, including the nonrandomized contralateral-eye design, which may have introduced selection bias, and the small sample size, which limited statistical power to detect rare adverse events. Functional assessments such as electroretinography and visual acuity could not be performed in the neonatal population, and long-term neurodevelopmental outcomes were not evaluated.

Despite these constraints, the findings provide meaningful preliminary data to inform future large-scale randomized controlled trials. The authors emphasized the importance of expanding research to include long-term follow-up and comprehensive visual function testing.

The study underscores the potential for biosimilars to broaden treatment access and reduce healthcare costs in pediatric ophthalmology.

“Given the growing global burden of ROP and the financial constraints of many health systems, biosimilars like Stivant could play a critical role in ensuring that effective treatments reach every infant who needs them,” the authors concluded.

1. Abrishami M, Golmohammadi Z, Shoeibi N, et al. Comparative efficacy and safety of biosimilar bevacizumab (Stivant) versus reference product (Avastin) in prethreshold type I retinopathy of prematurity. 

. 2025;36(4):407-412. doi:10.4103/joco.joco_178_24

2. García H, Villasis-Keever MA, Zavala-Vargas G, Bravo-Ortiz JC, Pérez-Méndez A, Escamilla-Nùñez A. Global prevalence and severity of retinopathy of prematurity over the last four decades (1985–2021): a systematic review and meta-analysis. 

A new study reveals Stivant, a bevacizumab biosimilar, matches Avastin in safety and efficacy for treating retinopathy of prematurity in infants.

Biosimilar Bevacizumab Matches Avastin in Treating Retinopathy of Prematurity

FDA approves Celltrion's Eydenzelt, a new aflibercept biosimilar, enhancing treatment options for retinal diseases in the US. | Image credit: Tada Images - stock.adobe.com

The FDA has approved Eydenzelt (aflibercept-boav), an aflibercept biosimilar developed by Celltrion to reference Eylea (aflibercept), an anti–vascular endothelial growth factor used to treat retinal diseases.

The American approval comes after the same biosimilar received marketing authorization from the European Commission in February 2025.

"Timely access to effective therapies is essential for individuals affected by retinal diseases. We are proud to have Eydenzelt approved by the FDA, and we look forward to expanding the availability and access of biological treatments across the US," said Juby Jacob-Nara, PhD, senior vice president and chief medical officer at Celltrion USA.

 "With Eydenzelt demonstrating biosimilarity to its reference product, we believe this approval will mark a significant milestone in the treatment landscape of retinal diseases—helping physicians broaden their options and improving patient outcomes."

Aflibercept products are administered intravitreally in a physician's office and are designed to block the growth of new blood vessels and decrease vascular permeability in the eye, 2 factors involved in ocular angiogenesis.

Eydenzelt is approved for the treatment of neovascular (wet) age-related macular degeneration, macular edema following retinal vein occlusion, diabetic macular edema (DME), and diabetic retinopathy.

The FDA based its approval on a totality of evidence, including analytical, nonclinical, and clinical data.

In a randomized, double-masked, parallel-group, multicenter phase 3 study, the efficacy, safety, pharmacokinetics, and immunogenicity of Eydenzelt were compared with Eylea in patients with DME. 

The primary end point was the change in best corrected visual acuity from baseline to week 8, comparing Eydenzelt with Eylea. The 52-week trial enrolled 348 patients with DME. Results showed that Eydenzelt met the predefined equivalence criteria, and secondary end points related to efficacy, safety, and immunogenicity demonstrated trends consistent with those observed for Eylea.

Eydenzelt represents Celltrion’s first FDA-approved biologic product in ophthalmology. It is also the sixth aflibercept approval in the US, following the FDA's authorizations of Pavblu (aflibercept-ayyh), Enzeevu (aflibercept-abzv), Ahzantive (aflibercept-mrbb), Yesafili (aflibercept-jbvf), and Opuviz (aflibercept-yszy).

Celltrion receives U.S. FDA approval for Eydenzelt (aflibercept-boav), biosimilar referencing Eylea (aflibercept). News release. Celltrion. October 9, 2025. Accessed October 13, 2025. 

https://www.celltrion.com/en-us/company/media-center/press-release/4201

Jeremias S. EC approves Celltrion denosumab, aflibercept biosimilars. The Center for Biosimilars

. February 20, 2025. Accessed October 13, 2025. 

https://www.centerforbiosimilars.com/view/ec-approves-celltrion-denosumab-aflibercept-biosimilars

Jeremias S. FDA approves Pavblu for retinal conditions. The Center for Biosimilars. September 17, 2024. Accessed October 13, 2025. 

https://www.centerforbiosimilars.com/view/fda-approves-pavblu-for-retinal-conditions

Jeremias S. FDA approves biosimilar Enzeevu for eye conditions. The Center for Biosimilars. August 12, 2024. Accessed October 13, 2025. 

https://www.centerforbiosimilars.com/view/fda-approves-biosimilar-enzeevu-for-eye-conditions

The FDA has approved Celltrion's Eydenzelt, a new aflibercept biosimilar, enhancing treatment options for retinal diseases in the US.

Skylar Jeremias

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