MICRHOGAM, RHOGAM Drug Profile

Summary for Tradename: MICRHOGAM, RHOGAM

High Confidence Patents:	0
Applicants:	1
BLAs:	1

Pharmacology for MICRHOGAM, RHOGAM

Mechanism of Action	Endogenous Antigen Neutralization
Physiological Effect	Passively Acquired Immunity
Established Pharmacologic Class	Human Immunoglobulin G
Chemical Structure	Immunoglobulins

Note on Biologic Patents

Matching patents to biologic drugs is far more complicated than for small-molecule drugs.

DrugPatentWatch employs three methods to identify biologic patents:

1. Brand-side disclosures in response to biosimilar applications

These patents were identified from disclosures by the brand-side company, in response to a potential biosimilar seeking to launch. They have a high certainty of blocking biosimilar entry. The expiration dates listed are not estimates — they're expiration dates as indicated by the brand-side company.

2. DrugPatentWatch analysis and company disclosures

These patents were identified from searching various sources, including drug labels and other general disclosures from the brand-side company. This list may exclude some of the patents which block biosimilar launch, and some of these patents listed may not actually block biosimilar launch. The expiration dates listed for these patents are estimates, based on the grant date of the patent.

3. Patents from broad patent text search

For completeness, these patents were identified by searching the patent literature for mentions of the branded or ingredient name of the drug. Some of these patents protect the original drug, whereas others may protect follow-on inventions or even inventions casually mentioning the drug. The expiration dates listed for these patents are estimates, based on the grant date of the patent.

1) High Certainty: US Patents for MICRHOGAM, RHOGAM Derived from Brand-Side Litigation

No patents found based on brand-side litigation

2) High Certainty: US Patents for MICRHOGAM, RHOGAM Derived from DrugPatentWatch Analysis and Company Disclosures

No patents found based on company disclosures

3) Low Certainty: US Patents for MICRHOGAM, RHOGAM Derived from Patent Text Search

No patents found based on company disclosures

MICRhoGAM and RhoGAM Market Dynamics, Financial Trajectory, and Patent Risk

Last updated: September 24, 2026

RhoGAM and MICRhoGAM are mature, plasma-derived anti-D immune globulin products marketed in the United States by Kedrion Biopharma. Their commercial value is driven by recurring obstetric prophylaxis, limited supplier competition, plasma collection requirements, and hospital purchasing contracts rather than by patent exclusivity. Product-level revenue is not publicly disclosed, and Kedrion is privately held. The main risks are manufacturing capacity, plasma supply, regulatory compliance, reimbursement pressure, and substitution by competing Rho(D) immune globulin products.

What are RhoGAM and MICRhoGAM?

RhoGAM and MICRhoGAM contain human Rho(D) immune globulin, also called anti-D immunoglobulin or Rh immune globulin.

Product	Primary use	Standard dose	Commercial distinction
RhoGAM	Rh-negative pregnant patients exposed to Rh-positive fetal blood; prevention of Rh immunization in other sensitizing events	300 micrograms, equivalent to 1,500 IU	Standard-dose product
MICRhoGAM	Same general indication for early pregnancy events	50 micrograms, equivalent to 250 IU	Reduced-dose product, generally used through 12 weeks of gestation when clinically appropriate

RhoGAM is used after delivery of an Rh-positive or weak-D-positive infant and after events that may cause fetomaternal hemorrhage, including pregnancy loss, abortion, ectopic pregnancy, abdominal trauma, and invasive obstetric procedures. MICRhoGAM is designed for smaller potential fetal-maternal blood exposures, particularly early in pregnancy. The FDA-approved labeling specifies dose selection based on the timing and magnitude of exposure.[1]

Kedrion manufactures and markets the products in the United States. The products are derived from human plasma collected from donors with high anti-D antibody titers. That manufacturing model creates supply constraints that do not apply to conventional small-molecule generics.

Who owns and markets RhoGAM and MICRhoGAM?

Kedrion Biopharma is the current U.S. commercial sponsor and manufacturer associated with RhoGAM and MICRhoGAM. Kedrion acquired North American commercial rights from Bayer HealthCare in 2015.[2]

The products are part of Kedrion’s broader plasma-derived portfolio, which includes immunoglobulins, albumin, coagulation products, and specialty plasma therapies. RhoGAM is strategically important because it is a recognized obstetric brand with established hospital and physician-channel demand, even though it is older than most products in Kedrion’s portfolio.

Company and product structure

Item	Status
Product sponsor	Kedrion Biopharma Inc.
Active ingredient	Human Rho(D) immune globulin
Product type	Plasma-derived biologic
FDA pathway	Biologics license application
U.S. BLA	BLA 103705 is associated with RhoGAM/MICRhoGAM labeling
Main U.S. channels	Hospitals, obstetric practices, clinics, pharmacies, specialty distributors
Primary market	United States
Competitive category	Rho(D) immune globulin products

What is the FDA regulatory status of RhoGAM?

RhoGAM and MICRhoGAM are FDA-licensed biologic products. The FDA prescribing information identifies them as Rho(D) immune globulin products for prevention of Rh immunization.[1]

The principal regulatory requirements are:

• validated plasma donor screening;
• control of anti-D antibody potency;
• viral safety and pathogen-reduction controls;
• manufacturing consistency;
• sterility and product quality testing;
• postmarketing safety surveillance;
• compliance with biologics manufacturing requirements.

The principal regulatory barrier is manufacturing quality and source-plasma control. A company cannot enter the market merely by producing an equivalent chemical composition. It must obtain a biologics license supported by manufacturing, analytical, clinical, and safety data.

How large is the Rho(D) immune globulin market?

The market is a specialized segment of the plasma-derived immunoglobulin industry. Demand is linked mainly to:

1. the number of Rh-negative pregnancies;
2. the rate of prenatal and postpartum prophylaxis;
3. use after miscarriage, abortion, trauma, and invasive procedures;
4. compliance with obstetric guidelines;
5. availability of testing and administration infrastructure.

The relevant patient population is much smaller than the overall pregnancy market because only Rh-negative patients who have not already developed anti-D antibodies require prophylaxis. In the United States, roughly 15% of the population is Rh-negative, although prevalence varies by ancestry and geography. The total annual addressable volume is therefore measured in a defined subset of pregnancies and sensitizing events, not in all births.

A 300-microgram dose is typically used at approximately 28 weeks of gestation and again after delivery when indicated. Additional doses may be needed after a large fetomaternal hemorrhage. That recurring schedule supports stable baseline demand.

Key market drivers

Driver	Effect on market
Prenatal prophylaxis	Creates recurring demand before delivery
Postpartum prophylaxis	Creates a second routine demand point
Miscarriage and abortion care	Expands use beyond live births
Increased diagnosis of fetomaternal hemorrhage	Can increase dose requirements
Plasma collection constraints	Limits supply growth
Hospital purchasing consolidation	Pressures pricing and contract terms
Clinical familiarity with RhoGAM	Supports brand retention
Competing Rho(D) products	Limits pricing power

The market is relatively defensive because prophylaxis is guideline-supported and clinically important. Demand is less sensitive to discretionary consumer behavior than demand for many specialty drugs.

How does RhoGAM compare with competing Rho(D) immune globulin products?

The principal U.S. competitors include Rhophylac and other Rho(D) immune globulin products, depending on indication, formulation, and commercial availability.

Product	Company	General positioning
RhoGAM	Kedrion	Established U.S. obstetric brand
MICRhoGAM	Kedrion	Low-dose early-pregnancy product
Rhophylac	CSL Behring	Competing anti-D immunoglobulin product
HyperRHO S/D	Grifols	Rho(D) immune globulin product
WinRho SDF	Sobi or related commercial rights by market	Rho(D) immune globulin with broader historical positioning, including immune thrombocytopenic purpura

Competition is based on price, allocation reliability, dosing formats, distribution, hospital contracts, clinical familiarity, and manufacturer service. The products are not interchangeable solely because they contain anti-D antibodies. Institutions must evaluate labeled indications, potency, administration requirements, packaging, and procurement terms.

RhoGAM retains an advantage from long clinical use and name recognition. Rhophylac and other products can gain share when they offer supply reliability, preferred contracting terms, or operational advantages.

What patents protect RhoGAM and MICRhoGAM?

Patent protection is unlikely to be the primary barrier to entry for RhoGAM or MICRhoGAM. The products originated decades ago, and the core anti-D immune globulin technology is not dependent on a recent composition-of-matter patent.

The relevant protection is more likely to arise from:

• manufacturing know-how;
• donor selection and plasma-pooling processes;
• purification and viral-clearance methods;
• formulation and stability controls;
• analytical assays;
• trade secrets;
• regulatory approval history;
• supplier and distribution relationships.

Publicly available product information does not establish a current, commercially meaningful patent estate that would provide RhoGAM with a modern small-molecule-style exclusivity period. The Orange Book is not the central patent database for these biologics. The FDA Purple Book and biologics licensing records are more relevant to regulatory competition.[3]

Patent-strength assessment

Protection category	Assessment
Core composition patent	Low relevance because of product age
Formulation patent	No publicly established dominant current barrier
Method-of-use patent	Obstetric prophylaxis use is long established
Manufacturing patents	Potentially relevant, but often difficult to identify and enforce from public product data
Trade secrets	Likely commercially important
Regulatory exclusivity	Historical rather than a meaningful current barrier
Brand and clinical familiarity	Moderate commercial protection
Supply-chain access	High practical importance

When does RhoGAM lose exclusivity?

RhoGAM does not appear to have a conventional near-term patent cliff comparable to a recently approved branded drug. Its effective market protection comes from regulatory complexity, manufacturing requirements, plasma supply, and commercial execution.

For a biologic of this age, the relevant entry question is not simply whether a patent has expired. A competitor must obtain its own FDA license or pursue an applicable biologics pathway, demonstrate product quality and potency, establish manufacturing controls, and secure adequate anti-D plasma supply.

No meaningful current data indicate that RhoGAM has a remaining statutory exclusivity period that would prevent competing licensed Rho(D) immune globulin products. Competing products already exist in the category.

Generic and biosimilar entry risk

Traditional generic substitution is not the principal threat because RhoGAM is a biologic. A competitor would generally need to enter through a biologics regulatory pathway rather than an ordinary abbreviated new drug application.

Biosimilar risk is also limited by the nature of the product:

• anti-D immune globulin is a complex, polyclonal plasma-derived product;
• source plasma characteristics can vary;
• potency and antibody specificity must be controlled;
• manufacturing comparability is more complex than for a single monoclonal antibody;
• automatic substitution depends on FDA interchangeability status and state law.

The practical risk is therefore competitive biologic entry, not a large wave of pharmacy-substitutable generics.

What formulation patents protect RhoGAM and MICRhoGAM?

The commercial distinction between RhoGAM and MICRhoGAM is primarily dose and presentation rather than a new molecular entity. MICRhoGAM uses a lower anti-D dose for specified early-pregnancy exposures.

Potentially protectable technical elements include:

• low-dose concentration and fill volume;
• stabilizers and excipients;
• liquid or freeze-dried presentation;
• container closure;
• storage conditions;
• potency retention;
• prefilled syringe or vial configuration.

The publicly available labeling does not establish that a currently enforceable formulation patent is the main defense of either product. For products of this age, manufacturing quality, established approval, and supply capacity are more important than formulation exclusivity.

What patent litigation or Paragraph IV challenges affect RhoGAM?

No major public Paragraph IV challenge is associated with RhoGAM or MICRhoGAM in the conventional sense. Paragraph IV litigation is an abbreviated new drug application mechanism primarily associated with small-molecule products under the Hatch-Waxman framework.

For RhoGAM, the more relevant competitive disputes would involve:

• FDA licensing of a competing biologic;
• patent litigation over manufacturing or formulation technology;
• trademark disputes;
• distributor and supply agreements;
• product-liability claims;
• regulatory enforcement concerning plasma-derived products.

No major public patent settlement defining an imminent RhoGAM generic launch is identified in the cited FDA and company materials.

How does plasma supply affect RhoGAM revenue?

Plasma availability is a central economic variable. RhoGAM cannot be manufactured at scale without suitable anti-D plasma. Supply can be constrained by:

• donor recruitment;
• donor eligibility requirements;
• anti-D titer levels;
• collection-center capacity;
• testing and release timelines;
• competing demand for plasma-derived products;
• manufacturing interruptions;
• regulatory holds or quality investigations.

Supply constraints can support pricing and protect incumbent share, but they can also reduce revenue if the manufacturer cannot fulfill orders. A shortage can shift hospitals toward competing products and weaken customer retention even after supply normalizes.

The product’s economics are therefore different from those of a tablet. Capacity utilization, plasma yield, batch release, and inventory management can have a direct effect on annual sales.

What is the financial trajectory of RhoGAM and MICRhoGAM?

Kedrion does not publicly report audited revenue for RhoGAM or MICRhoGAM as separate product lines. The company is privately held, and public disclosures do not provide a reliable product-level revenue series, operating margin, or cash-flow history for the brands.

The financial trajectory can be assessed through market structure:

Financial variable	Likely direction
Unit demand	Stable to modestly growing with births and clinical utilization
Average price	Positive pressure from contracting and competitors, offset by supply constraints
Revenue volatility	Driven more by supply and allocation than by patent loss
Gross margin	Supported by specialty biologic pricing but exposed to plasma and manufacturing costs
R&D burden	Lower than for a newly developed biologic
Capital needs	Concentrated in plasma collection, manufacturing, quality systems, and regulatory compliance
Commercial risk	Moderate, with concentration around supply reliability and hospital contracts
Patent-cliff risk	Low
Replacement risk	Moderate over a long period from competing licensed products

RhoGAM likely generates mature-product economics: recurring demand, limited need for conventional clinical development, and relatively predictable utilization. Its margin profile can remain attractive if plasma supply and manufacturing yields are controlled. The principal downside is not abrupt patent erosion. It is gradual share loss, price compression, or supply disruption.

Kedrion’s broader corporate growth can come from immunoglobulin demand, plasma-collection expansion, acquisitions, geographic expansion, and product mix. RhoGAM’s contribution should be evaluated as a stable specialty franchise rather than as a high-growth asset.

What licensing deals affect RhoGAM?

The key disclosed transaction was Kedrion’s acquisition of North American commercial rights from Bayer HealthCare in 2015.[2] That transaction transferred a mature branded product to a specialist plasma-derived therapeutics company with an existing commercial and manufacturing platform.

The strategic logic was straightforward:

• Bayer exited a non-core plasma-derived product area;
• Kedrion obtained an established obstetric brand;
• the product fit Kedrion’s immune globulin portfolio;
• commercial continuity reduced physician and hospital switching costs.

No major recent licensing transaction is required to explain RhoGAM’s current position. The brand’s economics depend more on manufacturing and distribution execution than on ongoing licensing innovation.

What generic launch scenarios exist for RhoGAM?

Scenario 1: Continued incumbent stability

Kedrion retains strong U.S. share, with competitors present but unable to displace the brand materially. Revenue remains stable, while pricing tracks hospital contracts and supply conditions.

Scenario 2: Gradual competitive erosion

Hospitals increase use of Rhophylac or another licensed product because of lower price, improved availability, or formulary preference. RhoGAM revenue declines gradually without a patent event.

Scenario 3: Supply-driven share loss

A manufacturing interruption or plasma shortage causes allocation problems. Competitors gain accounts that may not return after supply is restored.

Scenario 4: New biologic entrant

A new Rho(D) immune globulin product obtains FDA approval with improved packaging, dosing, manufacturing economics, or distribution. The entrant targets hospital systems and obstetric networks.

Scenario 5: Clinical-practice change

Broader use of fetal RhD genotyping or more selective prophylaxis could reduce unnecessary administration in some populations. The effect would depend on adoption, reimbursement, and guideline changes.

What is the geographic coverage of RhoGAM?

RhoGAM has its strongest commercial relevance in the United States. Anti-D immune globulin products are marketed internationally under multiple brands and regulatory frameworks, but product names, indications, dose units, and distribution rights vary by country.

Geographic performance depends on:

• local Rh-negative prevalence;
• national prenatal-care standards;
• reimbursement;
• availability of fetal RhD testing;
• hospital procurement structures;
• local plasma regulation;
• competing anti-D products.

The United States remains commercially important because prophylaxis is well established and the product has extensive brand recognition. International growth is constrained by country-specific regulatory approvals and established local competitors.

What is the investment and licensing view of RhoGAM?

RhoGAM is best characterized as a mature, defensible specialty biologic with low patent-cliff risk and moderate operational risk.

For investors or licensees, the central diligence questions are:

• Can Kedrion maintain reliable anti-D plasma access?
• Is manufacturing capacity sufficient for peak demand?
• Are hospital contracts renewing at acceptable prices?
• How much share is moving to Rhophylac and other competitors?
• Are there FDA observations, recalls, or supply interruptions?
• Does Kedrion disclose product-level or segment-level growth?
• Are new anti-D products approaching FDA approval?
• Is fetal RhD genotyping reducing prophylaxis volume?
• What proportion of sales comes from the United States?
• Are reimbursement changes affecting administration and product economics?

The asset has limited conventional discovery risk but meaningful supply-chain and commercial-execution risk. Its value is tied to durable clinical demand, recognized branding, and barriers to producing plasma-derived biologics at consistent scale.

Key Takeaways

• RhoGAM and MICRhoGAM are mature anti-D immune globulin products marketed in the United States by Kedrion Biopharma.
• RhoGAM is the standard-dose product; MICRhoGAM is the lower-dose product for specified early-pregnancy exposures.
• The products are FDA-licensed biologics and are not exposed to a conventional near-term small-molecule patent cliff.
• No major current Paragraph IV challenge or public patent settlement defines the competitive outlook.
• The strongest barriers are anti-D plasma supply, manufacturing controls, regulatory compliance, and hospital distribution.
• Product-level revenue and profitability are not publicly disclosed.
• Revenue is likely stable to moderately growing, with volatility driven by supply, contracting, and competing licensed products.
• The primary competitive threats are Rhophylac, HyperRHO, and other Rho(D) immune globulin products, not ordinary generic tablets.
• Biosimilar substitution risk is limited by the complexity of polyclonal plasma-derived products.
• The most material long-term risks are supply disruption, price pressure, competitor switching, and wider use of fetal RhD genotyping.

FAQs

Is RhoGAM a biologic or a generic drug?

RhoGAM is a plasma-derived biologic containing human Rho(D) immune globulin. It is not a conventional small-molecule generic drug.

Is MICRhoGAM interchangeable with RhoGAM?

They contain the same general active biologic, but they have different dose strengths and labeled use cases. Selection depends on the size and timing of the Rh-positive blood exposure.

Does RhoGAM have Orange Book patents?

The Orange Book is not the principal source for assessing RhoGAM’s biologic competition. FDA biologics records and the Purple Book are more relevant. The product’s commercial position is not primarily based on a currently visible Orange Book patent estate.

Who competes with Kedrion in the Rho(D) immune globulin market?

CSL Behring’s Rhophylac and Grifols’ HyperRHO are important competing products. Other products may compete depending on market, indication, and availability.

What would most likely reduce RhoGAM sales?

The most likely causes are sustained hospital conversion to competing products, supply disruption, lower pricing in procurement contracts, and selective use of prophylaxis following wider adoption of fetal RhD genotyping.

References

1. U.S. Food and Drug Administration. (2023). RhoGAM Ultra-Filtered PLUS and MICRhoGAM Ultra-Filtered PLUS prescribing information. Kedrion Biopharma Inc.

2. Kedrion Biopharma. (2015). Kedrion acquires North American rights to RhoGAM and MICRhoGAM from Bayer HealthCare. Company announcement.

3. U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products. https://purplebooksearch.fda.gov/