Last updated: September 8, 2026
ULTOMIRIS, AstraZeneca’s ravulizumab-cwvz, is a long-acting C5 complement inhibitor used in paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, generalized myasthenia gravis, and neuromyelitis optica spectrum disorder in applicable jurisdictions. Its commercial trajectory is driven by conversion from SOLIRIS, expansion into new complement-mediated diseases, and dosing intervals of up to eight weeks for many adult patients. The principal risks are competing C5 and proximal-complement inhibitors, high payer scrutiny, biosimilar development, and eventual loss of exclusivity.
What is ULTOMIRIS and which indications drive sales?
ULTOMIRIS contains ravulizumab, a humanized monoclonal antibody that inhibits complement component C5. By preventing C5 cleavage, it suppresses formation of terminal complement complex while preserving upstream complement activity.
| Item |
ULTOMIRIS detail |
| Active ingredient |
Ravulizumab |
| Sponsor |
Alexion Pharmaceuticals, AstraZeneca |
| Drug class |
Long-acting terminal complement C5 inhibitor |
| Initial U.S. approval |
December 2018 |
| First indication |
Adult PNH |
| Additional U.S. indications |
aHUS, adult generalized myasthenia gravis, pediatric PNH and aHUS |
| Administration |
Intravenous infusion; weight-based loading and maintenance |
| Adult maintenance interval |
Generally every eight weeks after loading |
| Primary predecessor |
SOLIRIS, eculizumab |
| Main commercial advantage |
Less frequent dosing than SOLIRIS |
The product initially replaced SOLIRIS in PNH and aHUS. AstraZeneca then expanded the label to generalized myasthenia gravis, adding a much larger potential patient population than the ultra-rare hematology and renal indications. The U.S. Food and Drug Administration approved ULTOMIRIS for adult generalized myasthenia gravis in 2022. FDA approval for adult patients with anti-aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder followed in 2024.[1,2]
gMG is commercially important because treatment is chronic, the eligible population is larger than in PNH or aHUS, and neurologists can use complement inhibition in patients with severe disease despite standard therapy. NMOSD expands the addressable market but faces competition from approved biologics, including eculizumab, inebilizumab, and satralizumab.
How has ULTOMIRIS revenue developed?
ULTOMIRIS has been one of AstraZeneca’s fastest-growing rare-disease products. Sales growth reflects conversion from SOLIRIS, increased penetration in PNH and aHUS, and the gMG launch.
| Fiscal year |
ULTOMIRIS reported product sales |
Primary growth driver |
| 2021 |
Approximately $1.4 billion |
PNH and aHUS conversion |
| 2022 |
Approximately $2.4 billion |
Broader conversion and gMG launch |
| 2023 |
Approximately $3.1 billion |
gMG uptake and continued SOLIRIS migration |
| 2024 |
Approximately $4.5 billion |
gMG growth, PNH conversion, and broader rare-disease use |
Sources: AstraZeneca annual reports and financial disclosures.[3-6]
The sales curve shows a classic product-lifecycle transition from a replacement franchise to a multi-indication franchise. Early revenue came primarily from patients switching from SOLIRIS. Later growth depended more heavily on new starts in gMG and other indications.
AstraZeneca’s broader Alexion rare-disease business has also benefited from ULTOMIRIS replacing SOLIRIS as the preferred terminal complement inhibitor. ULTOMIRIS is now central to the economics of the Alexion portfolio, while SOLIRIS functions increasingly as a legacy product and, in some markets, as a treatment option where reimbursement or local contracting favors the older therapy.
When does ULTOMIRIS lose exclusivity?
ULTOMIRIS does not have a single global loss-of-exclusivity date. Exclusivity depends on patent claims, regulatory exclusivity, pediatric extensions, jurisdiction, and the timing of biosimilar approvals.
The product’s core patent estate is expected to provide protection into the 2030s in the United States and other major markets. Patent duration may be extended or narrowed by patent-term adjustment, patent-term extension, post-grant proceedings, litigation, and the scope of individual claims. The practical risk window is therefore later than the initial biologic exclusivity period but earlier than the last possible patent expiration in every jurisdiction.
U.S. exclusivity and Orange Book status
The FDA Orange Book is relevant to ULTOMIRIS only to the extent that FDA-listed patents cover the approved product, formulation, or method of use. Biologics approved under the Public Health Service Act are not generally handled through the same Orange Book patent-certification framework used for small-molecule drugs under the Hatch-Waxman Act. Biosimilar applicants instead use the Biologics Price Competition and Innovation Act patent-exchange process.
Relevant U.S. protection can include:
- Antibody composition claims covering ravulizumab or related anti-C5 antibodies.
- Formulation claims covering concentration, stabilizers, buffers, or storage conditions.
- Manufacturing claims covering cell culture, purification, or product quality.
- Method-of-use claims for PNH, aHUS, gMG, and NMOSD.
- Dosing claims covering the long-interval administration schedule.
The strongest commercial protection is likely to come from composition and formulation claims that are difficult to design around. Disease-specific method claims may delay competing products in individual indications but are less effective against a biosimilar seeking broader approval through the 351(k) pathway.
Regulatory exclusivity
Ravulizumab benefits from biologic regulatory exclusivity separate from patents. The BPCIA generally provides 12 years of reference-product exclusivity in the United States, subject to statutory rules governing the reference product and approval date. ULTOMIRIS also received pediatric exclusivity associated with certain pediatric indications, which can add six months to applicable periods of exclusivity.
Regulatory exclusivity does not prevent all competitive development. A biosimilar applicant can begin development before patent expiry, and the sponsor can face patent litigation before a biosimilar launches.
Which companies are challenging ULTOMIRIS?
ULTOMIRIS faces competition from both direct C5 inhibitors and drugs that block complement at earlier points in the pathway.
| Competitor |
Company |
Mechanism |
Competitive position |
| SOLIRIS |
AstraZeneca/Alexion |
C5 inhibition |
Internal predecessor; remains a commercial comparator |
| EMPAVELI |
Apellis |
C3 inhibition |
Broader complement blockade; approved for PNH |
| FABHALTA |
Novartis |
Factor B inhibition |
Oral proximal complement inhibitor for PNH |
| VOYDEYA |
AstraZeneca |
Factor D inhibition |
Add-on therapy for extravascular hemolysis in PNH |
| crovalimab |
Roche |
C5 inhibition |
Long-acting subcutaneous and intravenous option in PNH |
| Iptacopan |
Novartis |
Factor B inhibition |
Oral therapy with potential convenience advantages |
| Eculizumab biosimilars |
Multiple developers |
C5 inhibition |
Future price competition after approval and launch |
The most direct threats differ by indication. In PNH, ULTOMIRIS competes against oral proximal-complement inhibitors and subcutaneous or long-acting C5 products. In gMG and NMOSD, treatment choice depends on biomarker status, disease severity, physician familiarity, administration burden, prior therapy, and payer policy.
Oral agents present the clearest convenience challenge. ULTOMIRIS requires infusion-center or home-infusion infrastructure, while oral products avoid intravenous administration. ULTOMIRIS retains an advantage where physicians value established terminal-pathway efficacy, durable exposure, and the transition pathway from SOLIRIS.
How strong is the ULTOMIRIS patent estate?
The estate is commercially strong but not immune to erosion. Its principal strengths are the value of the ravulizumab molecule, the difficulty of reproducing a biologic with an interchangeable profile, and the breadth of chronic indications.
Strengths
- Long-acting pharmacokinetic design supports recurring use and creates formulation and dosing claims.
- Multiple indications provide separate enforcement and settlement opportunities.
- PNH and aHUS are highly specialized diseases with substantial treatment complexity.
- Switching patients from SOLIRIS creates clinical and commercial continuity.
- Manufacturing know-how and analytical comparability can raise biosimilar development barriers.
Weaknesses
- Method-of-use patents may be vulnerable to noninfringement arguments and skinny-label strategies.
- A biosimilar does not need to reproduce every commercial feature of ULTOMIRIS.
- Oral complement inhibitors can compete without infringing ravulizumab composition claims.
- Some formulation and dosing claims may have limited value if a competing product uses a different presentation.
- Payers may prefer lower-cost products in chronic indications once credible alternatives reach the market.
The estate is strongest against a direct ravulizumab biosimilar and weaker against mechanism-adjacent products that inhibit C3, factor B, or factor D.
What generic, biosimilar, and launch risks exist?
Traditional generic entry is not the relevant risk because ULTOMIRIS is a biologic. The commercial threat comes from biosimilars and alternative complement inhibitors.
Biosimilar risk
A ULTOMIRIS biosimilar would need to demonstrate high similarity to ravulizumab and could seek approval for multiple indications through extrapolation. Key barriers include:
- Complex antibody characterization.
- Demonstration of comparable pharmacokinetics and immunogenicity.
- Manufacturing capacity for a high-value monoclonal antibody.
- Clinical and regulatory requirements for complement-mediated diseases.
- Patent litigation and the BPCIA information-exchange process.
- Physician and payer confidence in switching.
A biosimilar could launch first in PNH or another indication where payer savings are strongest. An interchangeable designation, if obtained, would increase substitution potential at the pharmacy or institutional level, although ULTOMIRIS is largely administered through infusion channels rather than conventional retail dispensing.
Alternative-mechanism risk
Alternative complement products may erode ULTOMIRIS without waiting for its patents to expire. Oral factor B inhibition is especially relevant because it reduces infusion burden. C3 inhibition may offer broader pathway suppression but can create different safety, vaccination, and monitoring considerations.
What patent litigation and settlement issues affect ULTOMIRIS?
The most important future litigation will likely involve biosimilar applicants challenging ravulizumab patents or seeking noninfringing launch strategies. The BPCIA process can produce several outcomes:
- A negotiated launch date before the last asserted patent expires.
- A court decision invalidating or narrowing key claims.
- A settlement that allows launch after a defined date.
- A launch limited to non-patent-protected indications.
- A commercial launch accompanied by ongoing damages or injunction litigation.
Publicly visible litigation risk should be assessed patent by patent rather than through a single exclusivity date. Composition claims generally present the highest launch risk. Manufacturing, formulation, and indication claims can delay a competitor but may permit design-around strategies.
How does ULTOMIRIS compare with SOLIRIS?
| Factor |
ULTOMIRIS |
SOLIRIS |
| Active ingredient |
Ravulizumab |
Eculizumab |
| Dosing interval |
Generally every eight weeks in adults |
Generally every two weeks |
| Commercial role |
Growth product and franchise successor |
Mature predecessor |
| Administration |
Intravenous |
Intravenous |
| Switching rationale |
Lower infusion frequency and reduced treatment burden |
Established clinical history |
| Revenue trajectory |
Rapid growth |
Mature or declining |
| Competitive vulnerability |
Future biosimilar and oral-agent exposure |
Earlier loss-of-exclusivity pressure |
ULTOMIRIS extends the Alexion complement franchise rather than replacing its economics immediately. Conversion protects revenue as SOLIRIS matures, while longer dosing intervals support physician and patient retention. The risk is that the successor product inherits the pricing expectations of a high-cost chronic biologic while facing increasingly convenient alternatives.
What is the commercial outlook for ULTOMIRIS?
ULTOMIRIS should remain a multibillion-dollar product through the second half of the decade if AstraZeneca maintains leadership in PNH, expands gMG and NMOSD use, and manages payer access. Growth will decelerate as the SOLIRIS conversion pool shrinks.
The principal revenue drivers are:
- Continued conversion of SOLIRIS patients.
- New gMG starts and treatment persistence.
- NMOSD uptake in biomarker-defined patients.
- International reimbursement expansion.
- Home-infusion and administration models that reduce treatment burden.
- Lifecycle management through pediatric use and combination strategies.
The principal revenue risks are:
- Oral proximal-complement inhibitors.
- Long-acting subcutaneous C5 competitors.
- Payer-mandated step therapy.
- Biosimilar entry.
- Reduced net pricing from contracting.
- Safety or immunization requirements associated with terminal complement blockade.
- Slower uptake in indications with several established biologic options.
A reasonable commercial scenario is continued sales growth through the late 2020s, followed by slower growth or plateauing as new indications mature and competitors gain share. The magnitude of post-exclusivity erosion will depend more on biosimilar interchangeability, payer substitution policies, and the availability of oral alternatives than on patent expiry alone.
Key Takeaways
- ULTOMIRIS is AstraZeneca’s principal long-acting C5 inhibitor and the successor to SOLIRIS.
- Reported sales increased from approximately $1.4 billion in 2021 to approximately $4.5 billion in 2024.
- PNH and aHUS established the franchise; gMG and NMOSD provide the main expansion opportunities.
- The product’s core patent and regulatory protection extends into the 2030s in major markets, although exact launch timing depends on individual patents and litigation.
- Biosimilar risk is distinct from traditional generic risk and will be governed by the BPCIA pathway.
- Oral factor B inhibitors, C3 inhibitors, and subcutaneous C5 inhibitors can erode ULTOMIRIS before direct biosimilar competition.
- ULTOMIRIS remains commercially strong, but revenue growth should moderate as SOLIRIS conversion matures and competitive alternatives improve.
Frequently Asked Questions
Is ULTOMIRIS a biologic or a generic drug?
ULTOMIRIS is a biologic monoclonal antibody. Competitive copies would be biosimilars, not traditional small-molecule generics.
How often is ULTOMIRIS administered?
Most adult patients receive maintenance treatment every eight weeks after a weight-based loading dose. Pediatric schedules vary by body weight.
Is ULTOMIRIS interchangeable with SOLIRIS?
The products have different active ingredients, ravulizumab and eculizumab. Switching is clinically possible under physician supervision, but ULTOMIRIS is not simply a generic substitute for SOLIRIS.
Which oral drug is the strongest commercial competitor to ULTOMIRIS?
Oral proximal-complement inhibitors, particularly factor B inhibitors such as iptacopan, present the clearest convenience-based threat because they eliminate routine intravenous infusion.
Does ULTOMIRIS have an FDA-approved use in myasthenia gravis?
Yes. FDA approved ravulizumab for adults with generalized myasthenia gravis in 2022.
Sources
- U.S. Food and Drug Administration. (2018). FDA approves ravulizumab-cwvz for paroxysmal nocturnal hemoglobinuria.
- U.S. Food and Drug Administration. (2024). ULTOMIRIS prescribing information.
- AstraZeneca. (2022). Annual report and Form 20-F 2022.
- AstraZeneca. (2023). Annual report and Form 20-F 2023.
- AstraZeneca. (2024). Full-year and fourth-quarter results 2023.
- AstraZeneca. (2025). Annual report and Form 20-F 2024.
- U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products.
- U.S. Food and Drug Administration. (2024). ULTOMIRIS: Prescribing information.
