Tag: biosimilars

The First Biosimilars to Simponi and Simponi Aria Just Got FDA Approval. Here Is What Immgolis and Immgolis Intri Are, What They Treat, and Why You Cannot Buy Them Yet.

📌 The essentials On May 15, 2026, the FDA approved Immgolis (golimumab-sldi, Accord BioPharma) as an interchangeable biosimilar to Simponi (golimumab, Janssen), and Immgolis Intri (golimumab-sldi) as an interchangeable biosimilar to Simponi Aria (golimumab, Janssen). These are the first FDA-approved biosimilars to either reference product. Both share the same INN suffix: golimumab-sldi. Developed by Bio-Thera Solutions; commercialized in the U.S. by Accord BioPharma (a subsidiary of Intas Pharmaceuticals). Immgolis approved indications: adults with moderately to severely active rheumatoid arthritis (RA) in combination with methotrexate, and adults with moderately to severely active ulcerative colitis (UC). Immgolis Intri approved indication: adults with moderately to severely active RA in combination with methotrexate only. Administration: Immgolis is subcutaneous injection (prefilled syringe); Immgolis Intri is intravenous infusion (single-dose vial). Both carry interchangeable designation, meaning pharmacists may substitute them at the counter without calling the prescriber, subject to state law. Critical caveat for patients: Accord BioPharma plans to make both products commercially available in Q4 2026. Launch is uncertain due to active BPCIA patent litigation filed by Janssen. Janssen filed a motion for preliminary injunction on May 6, 2026. A hearing is expected August to September 2026.

Golimumab (Simponi, Simponi Aria) is a fully human monoclonal antibody that blocks tumor necrosis factor alpha (TNF-alpha), the inflammatory cytokine that drives joint destruction in rheumatoid arthritis and the mucosal inflammation in ulcerative colitis. It is one of five TNF inhibitors currently approved in the United States. It generated approximately $1.19 to $1.2 billion in U.S. sales in 2025, making it a significant commercial target for biosimilar entry. And until May 15, 2026, not a single FDA-approved biosimilar existed for either formulation.

That changed when the FDA granted approval to Immgolis and Immgolis Intri, both developed by Bio-Thera Solutions and to be commercialized in the United States by Accord BioPharma. Both carry the coveted interchangeable designation, meaning pharmacists can substitute them for a Simponi or Simponi Aria prescription at the counter without contacting the prescriber first, in states where such substitution is permitted.

Whether patients will actually be able to access these products in the near term is a different question entirely. Active patent litigation filed by Janssen, including a preliminary injunction motion already before a federal court, means the actual launch date is uncertain even though the regulatory hurdle has been cleared.

This post covers what golimumab is and who uses it, what makes Immgolis and Immgolis Intri different from each other, what the interchangeable designation means in practice, why the Janssen lawsuit matters for access, and what patients on Simponi or Simponi Aria should know right now.

What Golimumab Is and Why It Matters in Autoimmune Disease

Golimumab is a fully human IgG1 monoclonal antibody that binds with high affinity and specificity to both soluble and transmembrane forms of human TNF-alpha, preventing it from interacting with its receptors on cell surfaces. TNF-alpha is a central mediator of the inflammatory cascade in multiple immune-mediated conditions. By neutralizing TNF-alpha, golimumab interrupts the downstream signaling that produces joint inflammation, synovial destruction, and intestinal mucosal damage.

When golimumab binds TNF-alpha, multiple pro-inflammatory biomarkers fall measurably: C-reactive protein (CRP), interleukin-6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), matrix metalloproteinase 3 (MMP-3), and vascular endothelial growth factor (VEGF) all decline. These reductions reflect the broad anti-inflammatory effect of TNF blockade at multiple downstream steps.

Golimumab is currently approved under two brand names with distinct delivery formats:

Simponi (golimumab) is a subcutaneous injection given once monthly using a prefilled syringe or autoinjector. It is approved for:

Moderately to severely active rheumatoid arthritis in combination with methotrexate
Active ankylosing spondylitis
Active psoriatic arthritis
Moderately to severely active ulcerative colitis in adults who have had inadequate response to conventional therapy

Simponi Aria (golimumab) is an intravenous infusion given at weeks 0 and 4, then every 8 weeks thereafter. It is approved for:

Moderately to severely active rheumatoid arthritis in combination with methotrexate

The two formulations are not interchangeable with each other: the same molecule is used at different doses and via different administration routes for different indications. This distinction carries through to the biosimilars as well.

Immgolis vs. Immgolis Intri: Two Products, One Molecule, Important Differences

Both Immgolis and Immgolis Intri share the same INN (international nonproprietary name): golimumab-sldi. They are derived from the same manufacturing process. However they are distinct products with distinct approved indications and routes of administration, and they should not be used interchangeably with each other.

	Immgolis (golimumab-sldi)	Immgolis Intri (golimumab-sldi)
Reference product	Simponi (golimumab)	Simponi Aria (golimumab)
Route of administration	Subcutaneous injection (prefilled syringe)	Intravenous infusion (single-dose vial)
Approved for RA	Yes, in combination with methotrexate	Yes, in combination with methotrexate
Approved for UC	Yes (moderately to severely active)	No
Approved for ankylosing spondylitis	No (not part of current approval)	No
Approved for psoriatic arthritis	No (not part of current approval)	No
Interchangeable designation	Yes	Yes
Commercially available	Q4 2026 (pending litigation outcome)	Q4 2026 (pending litigation outcome)

The indication scope of Immgolis and Immgolis Intri does not cover all of the indications currently on Simponi’s and Simponi Aria’s labels. Specifically, ankylosing spondylitis and psoriatic arthritis indications from the Simponi label are not included in the current Immgolis approval. Patients using Simponi for ankylosing spondylitis or psoriatic arthritis should not assume Immgolis is interchangeable for their specific indication until confirmed with their prescriber and insurer.

What Interchangeable Designation Means Here

Both Immgolis and Immgolis Intri received interchangeable designation from the FDA, the highest standard available for a biosimilar. This requires not only demonstrating biosimilarity (highly similar structure, function, and safety to the reference product) but also completing switching studies showing that patients who alternate between the biosimilar and the reference product do not experience greater risk or reduced efficacy compared to patients who remain on either product alone.

In practical terms, interchangeable designation means:

A pharmacist can substitute Immgolis for a Simponi prescription without contacting the prescriber first, in states that permit pharmacy-level substitution
A pharmacist can substitute Immgolis Intri for a Simponi Aria prescription under the same conditions
The FDA has determined that switching between the biosimilar and the reference product is clinically appropriate

The evidence basis for both approvals was described by the FDA as a comprehensive review of structural and functional product quality attributes, including those known to affect safety and efficacy, plus a human pharmacokinetic similarity study showing comparable drug exposure and immunogenicity results between Immgolis and Simponi.

For a broader explanation of how biosimilar and interchangeable designations work and why the distinction matters at the pharmacy counter, see our post on PONLIMSI and the denosumab biosimilar landscape, which covers this regulatory framework in detail.

Safety: The Boxed Warning and What Patients and Clinicians Need to Know

Immgolis and Immgolis Intri carry the same boxed warnings as their reference products. These warnings apply to the golimumab molecule regardless of which manufacturer produces it.

Boxed warning: serious infections and malignancy TNF inhibitors including golimumab increase the risk of serious infections that may lead to hospitalization or death, including tuberculosis (TB), bacterial sepsis, invasive fungal infections, and infections due to other opportunistic pathogens. Testing for latent tuberculosis is required before initiating therapy. Treatment of latent TB must be completed before starting golimumab in most cases. Monitor all patients for signs and symptoms of active infection during treatment. Lymphoma and other malignancies, some fatal, have been reported in children and adolescent patients treated with TNF blockers. Immgolis and Immgolis Intri are not approved for use in pediatric patients. In adult patients, an increased rate of lymphoma relative to the general population has been observed. The overall benefit-risk profile remains favorable for the approved indications, but the malignancy risk is a labeled concern requiring monitoring.

Additional warnings and precautions:

Hepatitis B reactivation: Screen for HBV infection before initiating treatment. Patients who are HBV surface antigen positive require antiviral prophylaxis in most cases. Fatal HBV reactivation has been reported with TNF inhibitors.
Demyelinating disorders: New onset or exacerbation of central and peripheral demyelinating disorders, including multiple sclerosis, have been reported with TNF blockers. Discontinue if these develop.
Heart failure: Worsening or new-onset congestive heart failure has been reported. Avoid use in patients with moderate to severe heart failure.
Autoimmune reactions: Drug-induced lupus-like syndrome is rare but reported. Discontinue if suspected.
Live vaccines: Do not administer live vaccines to patients receiving golimumab products. The diminished immune response may make vaccines less effective and live vaccines may cause infections.
Concomitant biologics: Use with abatacept, anakinra, or other biologic DMARD combinations increases the risk of serious infections and is generally not recommended.

Common adverse events from golimumab clinical experience include upper respiratory tract infections, nasopharyngitis, and injection site reactions for the subcutaneous formulation, and infusion-related reactions for the IV formulation.

The Janssen Patent Litigation: Why the Launch Date Is Uncertain

This is the most important practical piece of information for patients considering these products.

Regulatory approval and commercial availability are two distinct things, and the gap between them in this case is substantial.

The timeline of the litigation:

March 3, 2026: Janssen Biotech Inc. and Janssen Sciences Ireland UC filed a BPCIA (Biologics Price Competition and Innovation Act) patent infringement complaint against Bio-Thera Solutions and Accord BioPharma in the U.S. District Court for the District of Delaware (Case No. 1:26-cv-00222). The complaint asserts infringement of 17 patents related to golimumab, spanning manufacturing claims, method-of-treatment claims, and composition claims.
March 20, 2026: Accord, Intas, and Bio-Thera filed four inter partes review (IPR) petitions at the USPTO challenging four of the Janssen patents. The challenged patents cover method-of-treatment claims related to intravenous golimumab dosing.
May 6, 2026: Janssen filed a motion for preliminary injunction, seeking a court order that would block Accord and Bio-Thera from launching Immgolis and Immgolis Intri in the United States while the patent case is decided.
June 8, 2026: Accord BioPharma and Bio-Thera’s responsive brief to the preliminary injunction motion is due.
August to September 2026: Preliminary injunction hearing expected.
Q4 2026: Accord BioPharma’s stated launch target, which is contingent on the litigation outcome.

What a BPCIA preliminary injunction means The Biologics Price Competition and Innovation Act created specific procedures for patent disputes between reference product sponsors (like Janssen) and biosimilar applicants. A preliminary injunction is a court order that can halt commercial launch while the underlying patent dispute is resolved, even after FDA approval. If the court grants Janssen’s motion, Immgolis and Immgolis Intri could not be sold in the United States until the litigation concludes or the injunction is lifted, even though the FDA approval is final. If the court denies the motion, Accord and Bio-Thera can proceed with their planned Q4 2026 launch while litigation continues. The court’s decision on the preliminary injunction will depend on Janssen’s ability to show a likelihood of success on the merits of its patent claims and that irreparable harm would result from allowing the launch to proceed. Given that 17 patents are asserted, the litigation is likely to be complex and prolonged regardless of the preliminary injunction outcome.

The Alvotech/Teva context: A competing golimumab biosimilar (AVT05, golimumab) developed by Alvotech and Teva received a Complete Response Letter from the FDA in November 2025 following manufacturing concerns at Alvotech’s facility in Reykjavik, Iceland. Alvotech planned resubmission in Q2 2026. If AVT05 is ultimately approved, it would be the second golimumab biosimilar and would add competitive pricing pressure to the market.

What This Means for Patients on Simponi or Simponi Aria

Should you switch right now?

No. Immgolis and Immgolis Intri are approved but not yet commercially available. Accord BioPharma has stated a Q4 2026 launch target, which is subject to the litigation outcome. Patients currently stable on Simponi or Simponi Aria should remain on their current regimen until their rheumatologist initiates a conversation about any formulary change.

What will change when these products launch?

When Immgolis and Immgolis Intri become available, several things may happen depending on your insurance plan:

Your insurer may add one or both biosimilars to its preferred formulary tier, potentially lowering your copay if you switch
Your pharmacy may substitute the biosimilar for a Simponi or Simponi Aria prescription at the counter, given the interchangeable designation, and must notify you and your prescriber
Step therapy requirements could shift, with insurers potentially requiring biosimilar trial before covering the originator

What to do if your pharmacist substitutes a biosimilar

If your pharmacist substitutes Immgolis for your Simponi prescription or Immgolis Intri for your Simponi Aria prescription, they are required by law in most states to notify you of the substitution and to notify your prescriber. The FDA has determined these products are clinically interchangeable. If you have concerns about a substitution, you or your prescriber can request “dispense as written” on your prescription to prevent automatic substitution.

What cannot be substituted for what

Immgolis (subcutaneous) is interchangeable with Simponi, not with Simponi Aria. Immgolis Intri (intravenous) is interchangeable with Simponi Aria, not with Simponi. The two Immgolis products cannot be substituted for each other, because they have different routes of administration, doses, and indications.

Additionally, Immgolis and Immgolis Intri do not yet carry indications for ankylosing spondylitis or psoriatic arthritis. Patients using Simponi for either of those conditions should discuss with their rheumatologist before any switch is considered.

The Broader Context: The Simponi Market and TNF Inhibitor Biosimilars

Simponi and Simponi Aria generated combined U.S. sales of approximately $1.19 to $1.2 billion in 2025, making golimumab one of the last major TNF inhibitors to face biosimilar competition. Adalimumab (Humira) now has more than a dozen approved biosimilars and has seen substantial price competition. Etanercept (Enbrel) and infliximab (Remicade) have also seen biosimilar market entry. Golimumab has remained relatively insulated until now.

The arrival of interchangeable biosimilars is typically the moment at which meaningful price competition can begin, because interchangeability allows formulary switching at the pharmacy level without the prescriber friction that limits non-interchangeable biosimilars. Whether Immgolis and Immgolis Intri produce Simponi price reductions comparable to what adalimumab biosimilars achieved with Humira will depend on the litigation outcome, Accord’s pricing strategy, and the pace of formulary decisions by major pharmacy benefit managers.

Patients with rheumatoid arthritis and ulcerative colitis who are currently priced out of golimumab therapy have the most to gain from effective biosimilar competition. For those on Simponi for ankylosing spondylitis or psoriatic arthritis, the current Immgolis approval does not directly apply, though the existence of approved biosimilars may influence Janssen’s own pricing decisions over time.

For related HED coverage of the biosimilar market dynamics in other drug classes, see our post on PONLIMSI and why FDA biosimilar approvals do not automatically translate to patient savings and our post on interchangeable basal insulin biosimilars and what the approval of Langlara means for insulin access.

Sources

FDA approval announcement: FDA approves first interchangeable biosimilars to Simponi and Simponi Aria (golimumab) to treat rheumatoid arthritis and ulcerative colitis. FDA.gov. May 15, 2026.

Accord BioPharma press release: FDA Approves IMMGOLIS (golimumab-sldi) and IMMGOLIS INTRI (golimumab-sldi), First Biosimilars to Simponi (golimumab) and Simponi Aria (golimumab); Accord BioPharma to Lead U.S. Commercialization. PRNewswire. May 18, 2026.

Bio-Thera Solutions press release: Bio-Thera Solutions’ Golimumab Biosimilars Receive FDA Approval as First Biosimilars to Simponi and Simponi Aria. BioSpace. May 18, 2026.

Medscape clinical coverage: FDA Approves First Golimumab Biosimilars to Treat Rheumatoid Arthritis and Ulcerative Colitis. Medscape. May 18, 2026.

BioPharm International: FDA Approves First Golimumab Biosimilars from Accord BioPharma. biopharminternational.com. May 2026.

Drug Topics clinical summary: FDA Approves Golimumab-Sldi as First Biosimilar for Simponi. drugtopics.com. May 2026.

Patent litigation (Big Molecule Watch): FDA Approves First Interchangeable Biosimilars to Simponi and Simponi Aria; Janssen Seeks a Preliminary Injunction to Block Their Launch. bigmoleculewatch.com. May 22, 2026.

Janssen BPCIA complaint (Bloomberg Law): J&J’s Janssen Targets Accord Simponi Biosimilars in Patent Suit. bloomberglaw.com. March 2026.

Accord/Bio-Thera IPRs: Accord and Bio-Thera File Four IPRs Challenging Janssen Simponi Patents. biologicshq.com. March 27, 2026.

Pearce IP litigation summary: Bio-Thera/Accord BioPharma Secure First FDA Approval of Golimumab Biosimilars. pearceip.law. May 2026.

Simponi reference FDA approval: FDA approves golimumab (Simponi). FDA.gov.

Simponi Aria reference FDA approval: FDA approves golimumab (Simponi Aria). FDA.gov.

Golimumab mechanism: Golimumab. StatPearls. NCBI.

TNF-alpha biology: Tumor Necrosis Factor. StatPearls. NCBI.

CRP reference: C-Reactive Protein. StatPearls. NCBI.

BPCIA framework: Biosimilar Development, Review, and Approval. FDA.gov.

FDA interchangeable biosimilars: Biosimilar and Interchangeable Products. FDA.gov.

NIAMS RA overview: Rheumatoid Arthritis. niams.nih.gov.

NIAMS ankylosing spondylitis: Ankylosing Spondylitis. niams.nih.gov.

NIAMS psoriatic arthritis: Psoriatic Arthritis. niams.nih.gov.

NIDDK ulcerative colitis: Ulcerative Colitis. niddk.nih.gov.

TB testing before biologics: Testing for Latent TB Infection. CDC.

Patient resources: Arthritis Foundation | Crohn’s and Colitis Foundation | NIAMS Rheumatoid Arthritis

Disclaimer: Health Evidence Digest provides general information about FDA approvals and health research for educational purposes. This content is not a substitute for professional medical advice. Immgolis and Immgolis Intri are FDA-approved but not yet commercially available; planned Q4 2026 launch is subject to ongoing patent litigation. Decisions about switching between golimumab products should be made in consultation with a qualified rheumatologist or gastroenterologist familiar with your complete treatment history and indication.

May 23, 2026

Prolia Costs $2,500 a Dose. There Are Now 19 Biosimilar Competitors. Here’s What That Means for Patients.

📌 The essentials On March 30, 2026, Teva Pharmaceutical received FDA approval for PONLIMSI (denosumab-adet), a biosimilar to Prolia (denosumab, Amgen) for all five of Prolia’s approved indications. Commercial launch expected Q3 2026. This is the 19th FDA-approved denosumab biosimilar, not the first. Several have already launched commercially in the United States with modest savings of approximately 5 to 15% below Prolia’s list price. Critical distinction for patients: PONLIMSI is approved as a biosimilar but does NOT have interchangeable designation. Only Jubbonti (Sandoz) has interchangeable status for Prolia, meaning only Jubbonti can be substituted by a pharmacist without calling your prescriber. Simultaneously, Teva announced that the FDA and EMA have both accepted regulatory filings for its proposed omalizumab (Xolair) biosimilar. This is not an approval; it is the start of review. A Prolia discontinuation warning: do not stop denosumab abruptly for any reason, including a transition to a biosimilar. Rebound vertebral fractures are a documented serious risk. Any transition must be clinician-guided.

Osteoporosis affects an estimated 200 million people globally and is responsible for approximately 9 million fractures per year worldwide. In the United States, about 10 million adults have osteoporosis and another 44 million have low bone density, putting them at elevated fracture risk. Hip fractures in older adults carry a one-year mortality rate of up to 36%, a statistic that makes bone health a genuine life-or-death clinical priority, not a cosmetic concern.

Denosumab (Prolia, Amgen) is one of the most effective medications available for high-risk osteoporosis. It reduces vertebral fracture risk by up to 68%, hip fractures by 40%, and nonvertebral fractures by 20% in clinical trials. It is also, without insurance, a $2,506 injection administered twice a year, making it inaccessible or unaffordable for many of the patients who need it most.

On March 30, 2026, Teva Pharmaceutical received FDA approval for PONLIMSI (denosumab-adet), a biosimilar to Prolia, and simultaneously announced that regulatory agencies in both the U.S. and Europe have accepted filings for its proposed biosimilar to Xolair (omalizumab), a biologic used in severe asthma, nasal polyps, and IgE-mediated food allergy. These are meaningful regulatory events, but they exist in a context that the original announcement does not capture: the denosumab biosimilar market is now crowded, savings to patients have been disappointingly modest so far, and understanding the difference between a biosimilar and an interchangeable biosimilar has real implications for whether your pharmacist can make the switch without calling your doctor.

What Denosumab Does and Why It Is So Expensive

Denosumab is a fully human monoclonal antibody that works by inhibiting RANKL, receptor activator of nuclear factor kappa-B ligand, a protein essential for the formation, function, and survival of osteoclasts, the cells responsible for breaking down bone. By blocking RANKL, denosumab suppresses bone resorption, which allows bone mineral density to increase and fracture risk to fall.

Amgen markets denosumab under two brand names: Prolia (60 mg subcutaneous injection every 6 months) for osteoporosis and bone loss from hormonal cancer therapies, and Xgeva (120 mg every 4 weeks) for preventing skeletal-related events in patients with bone metastases and giant cell tumors. The two products use the same molecule but are approved for different indications at different doses.

The $2,500+ price per dose reflects the cost of biologic drug manufacturing. Denosumab is produced in living cells using complex, expensive processes, not synthesized chemically like a small molecule tablet. Amgen has generated approximately $2.9 billion annually from Prolia alone. Despite recent patent expirations in the U.S. and Europe opening the door to biosimilar competition, the denosumab market has yet to see the dramatic price reductions that biosimilar proponents hoped for.

A critical clinical nuance: the rebound fracture risk on discontinuation Denosumab has a well-documented risk of rebound vertebral fractures when treatment is stopped abruptly. Because denosumab’s anti-resorptive effect reverses quickly after the drug clears the system, faster than bisphosphonates which accumulate in bone tissue, stopping denosumab without transitioning to another therapy can produce a rapid spike in bone turnover that significantly increases fracture risk in the first 12 to 24 months after discontinuation. Multiple cases of simultaneous vertebral fractures following denosumab discontinuation have been reported in the literature. Current guidelines recommend that patients stopping denosumab for any reason, including switching to a biosimilar if the transition is not managed carefully, receive bridging therapy with a bisphosphonate. This is not a biosimilar-specific concern, but it is relevant for any patient or prescriber navigating a formulary switch or change in product.

PONLIMSI: What the Approval Is Based On

PONLIMSI (denosumab-adet) received FDA approval on March 30, 2026, based on a totality of evidence demonstrating comparable efficacy, safety, and immunogenicity to Prolia. This evidence includes data from a randomized, double-blind Phase 3 clinical trial (NCT04729621) enrolling 332 women with postmenopausal osteoporosis, comparing denosumab-adet directly against Prolia across these endpoints.

PONLIMSI is approved for all five indications of the reference product Prolia:

Indication	Patient Population
Postmenopausal osteoporosis	Women at high risk for fracture, including history of fracture or multiple risk factors; or failed or intolerant to other osteoporosis therapy
Male osteoporosis	Men at high risk for fracture
Glucocorticoid-induced osteoporosis	Men and women on long-term corticosteroid therapy at high risk for fracture
Prostate cancer bone loss	Men at high risk for fracture receiving androgen deprivation therapy for nonmetastatic prostate cancer
Breast cancer bone loss	Women at high risk for fracture receiving adjuvant aromatase inhibitor therapy for breast cancer

The EMA granted marketing authorization for PONLIMSI in Europe in November 2025, meaning the drug had already been approved in the EU before its U.S. clearance. Teva has indicated a commercial launch in the United States is expected in Q3 2026.

The Critical Distinction: Biosimilar vs. Interchangeable and Why It Matters for Patients

This is the most practically important piece of information in this post, and it was absent from the original coverage of PONLIMSI’s approval.

In the United States, there are two categories of FDA-approved biosimilars: biosimilar and interchangeable biosimilar. The difference matters at the pharmacy counter.

	Biosimilar	Interchangeable Biosimilar
FDA standard	Highly similar to reference product; no clinically meaningful differences in safety, purity, potency	Same as biosimilar PLUS: can be substituted without the prescriber’s involvement
Pharmacy substitution	Cannot be substituted automatically; requires prescriber authorization or new prescription in most states	Can be substituted by pharmacist without calling the prescriber (subject to state pharmacy laws)
Benefit to payer and patient	May require step therapy or prior authorization to access lower cost	Formulary substitution can happen more easily, driving faster cost competition
PONLIMSI status	Biosimilar only, NOT interchangeable (as of approval)	Jubbonti (Sandoz) has interchangeable designation
Real-world implication	Prescriber or insurer action typically needed	Pharmacist can swap without a call to the prescriber

Teva’s announcement did not mention an interchangeability designation for PONLIMSI. This means that in most U.S. states, a pharmacist cannot automatically substitute PONLIMSI for Prolia based on a prescription for denosumab. A clinician or insurer action is typically required. Patients who want to access the biosimilar version may need to ask their provider to write a new prescription specifically for PONLIMSI, or navigate a formulary preference process through their insurer.

The Denosumab Biosimilar Landscape: 19 Approvals, Modest Savings

PONLIMSI is not entering an empty market. By the time it launches in Q3 2026, it will be one of at least 19 FDA-approved denosumab biosimilars. Eighteen were approved by the end of December 2025, with PONLIMSI the first addition in 2026. Several have already launched commercially in the United States.

Biosimilar	Company	FDA Status	Notes
Jubbonti / Wyost	Sandoz	Approved March 2024; launched June 2025	First to market; interchangeable designation; 14.5% below Prolia WAC
Osenvelt / Stoboclo	Celltrion	Launched July 2025	5 to 10% discount range reported
Jubereq / Osvyrti	Accord BioPharma	Launched October 2025	Competitive pricing
Enoby / Xtrenbo	Gedeon Richter / Hikma	Approved; not yet launched	—
Bilprevda / Bildyos	Henlius / Organon	Approved; not yet launched	—
PONLIMSI	Teva	Approved March 2026; Q3 2026 launch expected	No interchangeability designation announced

The savings picture has been a disappointment relative to earlier expectations. Sandoz’s Jubbonti, the first approved interchangeable denosumab biosimilar, launched in June 2025 at a list price approximately 14.5% below Prolia’s wholesale acquisition cost. Celltrion’s biosimilars entered at an estimated 5 to 10% discount. A published budget impact model in the Journal of Medical Economics projected savings of $0.59 per member per month for health plans at medium conversion rates over five years, meaningful at scale, but not the 50 to 80% price reductions that biosimilar competition drove in markets like Europe.

Why are U.S. denosumab biosimilar savings so modest compared to Europe? In the UK, biosimilar adoption within the first year of launch routinely exceeds 90% of market share, driven by NHS tender-based procurement and institutional formulary switches. British rheumatologist Dr. Muhammad Nisar noted to Medscape that clinicians feel very comfortable with denosumab biosimilars, with great belief in their efficacy and safety. In the U.S., the market structure is fundamentally different. Amgen has kept Prolia competitively priced through rebates to pharmacy benefit managers (PBMs) and insurers. The net price paid by many payers may already be below the biosimilar list price after rebates. This perverse dynamic, in which originator rebates can make a brand-name drug cheaper to a payer than the biosimilar list price, is a structural feature of the U.S. drug market that dampens biosimilar adoption and competition. The interchangeability designation matters here too. Only Sandoz’s Jubbonti has interchangeable status for Prolia, allowing direct pharmacy substitution. The other approved denosumab biosimilars, including PONLIMSI, require prescriber action or payer-directed formulary changes to reach patients, slowing the pace of market conversion.

The Xolair Biosimilar Filing: A Different Market, A Different Opportunity

Teva’s simultaneous announcement that both the FDA and EMA have accepted filings for its proposed biosimilar to Xolair (omalizumab, Genentech/Novartis) is a separate and strategically distinct event from the PONLIMSI approval.

What omalizumab is and who uses it

Omalizumab (Xolair) is a monoclonal antibody that works by binding to free IgE, immunoglobulin E, the antibody class central to allergic responses, and blocking its interaction with IgE receptors on mast cells and basophils. By reducing free IgE levels, omalizumab prevents the downstream allergic cascade that produces symptoms in atopic disease.

Xolair is approved in the U.S. for: moderate-to-severe persistent allergic asthma inadequately controlled by inhaled corticosteroids in patients 6 and older whose asthma is related to a perennial allergen; chronic rhinosinusitis with nasal polyps in adults; chronic spontaneous urticaria in patients whose symptoms are inadequately controlled by antihistamines; and IgE-mediated food allergies in patients 1 year and older. That food allergy indication, the most recent addition, significantly expanded the patient population that might use omalizumab.

The market context

Global omalizumab sales are estimated at $3.5 to $3.7 billion annually, making this a commercially meaningful biosimilar target. Regulatory filing acceptance by both FDA and EMA simultaneously means Teva’s submission was complete enough for substantive review. This is not an approval; it is the beginning of the regulatory review process. The FDA’s standard review clock for biosimilar applications is 12 months from acceptance.

The omalizumab biosimilar market is at an earlier stage than denosumab. The omalizumab biosimilar landscape will be watched carefully by allergists, pulmonologists, and patients with severe allergic disease who currently pay thousands of dollars per year for brand-name Xolair, a cost that is a meaningful access barrier for many.

What This Means in Practice: Guidance for Patients

If you are currently on Prolia or another denosumab product

Do not stop denosumab without a medical plan for what comes next. The rebound fracture risk on discontinuation is real and serious. Any transition to a biosimilar should be clinician-guided, maintaining the same dosing schedule (every 6 months for Prolia indications) and likely incorporating a bisphosphonate bridge if you stop denosumab for any reason.

If cost is a barrier to accessing denosumab, ask your prescriber or pharmacist specifically about available biosimilar options. If your insurer’s formulary includes an interchangeable denosumab biosimilar like Jubbonti, your pharmacist may be able to substitute automatically. For non-interchangeable biosimilars like PONLIMSI, a prescriber action is required. Medicare Part B, through which administered biologics are often covered, has specific biosimilar substitution rules worth understanding with your provider.

If you are on Xolair for allergic asthma, nasal polyps, urticaria, or food allergy

A biosimilar is not yet available. Teva’s application is under review, and even after approval, launch timing will depend on regulatory processes and commercial decisions. Continue your current treatment as prescribed. Monitor your insurer’s formulary for updates in 2026 and 2027.

The Gap Between Biosimilar Approval and Patient Savings

The denosumab biosimilar story is instructive for understanding how U.S. drug pricing actually works and why regulatory approval of a biosimilar does not automatically translate to patient savings.

When Prolia’s key patents began expiring, the expectation was that biosimilar competition would drive meaningful price reductions, as it has in Europe. Instead, 19 FDA approvals later, the most aggressive biosimilar discount achieved is about 14.5% below Prolia’s list price. The originator still commands most of the market. The structural reasons are complex: Amgen’s rebate practices, the lack of interchangeability designation for most competitors, the physician-administered nature of the injection (which keeps it under Part B rather than Part D, with different substitution rules), and the clinical hesitancy around switching patients who have been stable on a therapy that must not be interrupted without a plan.

Flanigan et al. noted in their 2025 Journal of Medical Economics budget impact analysis that even a small discount of 5% for a biosimilar referencing Xgeva and Prolia could represent millions of dollars in savings for a health plan, with the potential for reinvestment to further expand access. Those savings are real at scale even when they feel modest at the individual patient level.

None of this means biosimilar approvals like PONLIMSI are without value. For payers, even modest per-dose discounts multiply across large patient populations. For patients in countries with less fragmented pricing structures, competitive biosimilar availability is genuinely transformative. And building a competitive biosimilar market, however slowly, creates the foundation for the price competition that patients deserve.

The omalizumab filing, if it leads to approval and launch, enters a somewhat less saturated biosimilar market. The recent addition of the food allergy indication has expanded the potential patient population substantially. That approval, if and when it comes, may be a more commercially differentiated moment than PONLIMSI in the already crowded denosumab space.

For related coverage of how access and affordability are shaping the drug landscape in 2026, see our post on FDA approval of the first generic dapagliflozin, where a similar story of high list prices, biosimilar or generic entry, and the gap between approval and real-world savings is unfolding in the type 2 diabetes space.

Sources

Teva press release: Teva Gains Biosimilar Momentum with U.S. FDA Approval of PONLIMSI (denosumab-adet) and Dual Filing Acceptance for Biosimilar Candidate to Xolair (omalizumab). March 30, 2026. ir.tevapharm.com.

Clinical Advisor coverage: FDA Approves Teva’s Prolia Biosimilar Ponlimsi, Accepts Xolair Biosimilar for Review. clinicaladvisor.com. April 2026.

Drug Topics: FDA Approves Denosumab-Adet as Biosimilar to Prolia. drugtopics.com. March 2026.

Center for Biosimilars: FDA Approves Teva Biosimilar for Denosumab in Osteoporosis. centerforbiosimilars.com. March 2026.

GaBI Online: FDA approves denosumab biosimilar Ponlimsi. gabionline.net. April 2026.

Medscape: Two More Denosumab Biosimilars Approved in the US. medscape.com. October 2025.

Managed Healthcare Executive: Biosimilar denosumab could save $0.59 per member per month. managedhealthcareexecutive.com. February 2026.

Journal of Medical Economics budget impact: Flanigan J, Chaplin S, et al. A budget impact model for biosimilar denosumab for skeletal-related events and fractures in the United States oncology population. J Med Econ. 2025;28(1):2027-2038. doi:10.1080/13696998.2025.2027-2038.

PONLIMSI Phase 3 trial: NCT04729621. ClinicalTrials.gov.

GoodRx pricing: How Much Is Prolia Without Insurance? goodrx.com.

Rebound fracture risk: Rebound vertebral fractures after denosumab discontinuation. PMC6683162.

Denosumab mechanism: Denosumab. StatPearls. NCBI.

RANKL biology: RANKL in bone biology. PMC3386061.

Hip fracture mortality: Hip fracture 1-year mortality. PMC6530614.

FDA biosimilars explained: Biosimilar and Interchangeable Products. FDA.gov.

FDA approved biosimilar products: FDA-Approved Biosimilar Products. FDA.gov.

Prolia FDA approval: FDA approves denosumab for osteoporosis. FDA.gov.

Xgeva FDA approval: FDA approves denosumab (Xgeva). FDA.gov.

Xolair FDA approval: FDA approves omalizumab for allergic asthma. FDA.gov.

IgE biology: IgE in allergy. StatPearls. NCBI.

PBM market structure: Pharmacy Benefit Managers. PMC7748166.

Bisphosphonates: Bisphosphonates. StatPearls. NCBI.

Patient resources: Bone Health and Osteoporosis Foundation | FDA Biosimilar Products List | GoodRx Prolia pricing

Disclaimer: Health Evidence Digest provides general information about FDA approvals and health research for educational purposes. This content is not a substitute for professional medical advice. Decisions about denosumab therapy, including switching between reference products and biosimilars, should be made in consultation with a qualified prescriber familiar with the patient’s bone health history and fracture risk. Never discontinue denosumab without medical guidance.

April 4, 2026