List of Excipients in Branded Drug OFIRMEV

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	CYSTEINE HYDROCHLORIDE
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	HYDROCHLORIC ACID
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	MANNITOL
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	NITROGEN
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	SODIUM HYDROXIDE
Mallinckrodt Hospital Products Inc	OFIRMEV	acetaminophen	43825-102	SODIUM PHOSPHATE, DIBASIC

Ofirmev Excipient Strategy and Commercial Opportunities in Intravenous Acetaminophen

Last updated: August 31, 2026

Ofirmev is an intravenous acetaminophen product containing 10 mg/mL acetaminophen. Its formulation uses mannitol and cysteine hydrochloride monohydrate in water for injection, with pH adjustment as needed. The main commercial opportunities are generic substitution, ready-to-use presentations, differentiated container systems, pediatric dosing, pharmacy workflow, and lower-cost manufacturing. The product’s principal barriers are formulation stability, dose-conversion safety, container compatibility, hospital contracts, and FDA requirements for injectable products.

What is Ofirmev and how is it formulated?

Ofirmev is an intravenous formulation of acetaminophen marketed for the management of mild-to-moderate pain and reduction of fever. It is administered intravenously over 15 minutes and is supplied at a concentration of 10 mg/mL.[1]

The labeled excipient system includes:

Component	Function
Acetaminophen	Active pharmaceutical ingredient
Mannitol	Tonicity adjustment and formulation support
Cysteine hydrochloride monohydrate	Antioxidant and degradation-control excipient
Water for injection	Vehicle
Hydrochloric acid or sodium hydroxide	pH adjustment, where required

Ofirmev is preservative-free. That characteristic supports use in hospital settings but increases the importance of aseptic manufacturing, container-closure integrity, oxygen control, and in-use handling.

What commercial problem does the Ofirmev formulation solve?

Intravenous acetaminophen gives hospitals a non-opioid analgesic and antipyretic option when oral or enteral administration is unavailable. Typical use cases include:

• Postoperative pain management
• Emergency-department fever reduction
• Perioperative multimodal analgesia
• Patients who are nil per os
• Patients with nausea, vomiting, ileus, or impaired gastrointestinal absorption
• Pediatric patients requiring weight-based dosing

The product does not create a new acetaminophen molecule or a new pharmacologic mechanism. Its value is based on route of administration, hospital workflow, and clinical utility.

What excipients protect Ofirmev stability?

Cysteine hydrochloride is the most strategically important excipient in the formulation. Acetaminophen injection is vulnerable to oxidative degradation, including formation of degradation products such as p-aminophenol. Cysteine can function as an oxygen-scavenging or reducing component, helping control oxidative pathways during manufacturing and storage.

Mannitol has a dual formulation role. It contributes to osmolality and can support the physical properties of the solution. The target osmolality must remain acceptable for intravenous administration while avoiding excessive tonicity that could limit tolerability.

The formulation strategy must control several variables:

Development variable	Commercial significance
Oxygen exposure	Affects oxidative degradation and shelf life
pH	Influences solubility, degradation, and infusion tolerability
Cysteine concentration	Controls stability but can affect odor, compatibility, and regulatory justification
Mannitol level	Affects osmolality and injection tolerability
Container material	Controls extractables, leachables, adsorption, and oxygen ingress
Headspace	Can affect oxidation over shelf life
Light exposure	May influence degradation and packaging requirements
Terminal sterilization	Must be balanced against degradation risk
Closure integrity	Critical for preservative-free injectable products

The excipient system is therefore part of the product’s intellectual-property and regulatory differentiation, even when the individual excipients are common pharmaceutical ingredients.

What formulations are protected by Ofirmev?

Ofirmev’s formulation protection historically centered on the composition and stabilization of intravenous acetaminophen rather than a broad new chemical entity patent estate. Product-specific protection may cover combinations of acetaminophen with stabilizers, concentration ranges, pH conditions, and methods of reducing degradation.

The principal formulation design space includes:

1. Acetaminophen concentration near 10 mg/mL.
2. A reducing or antioxidant excipient, including cysteine-based systems.
3. Mannitol or another tonicity-adjusting agent.
4. A defined pH range.
5. Preservative-free sterile aqueous administration.
6. Container and storage conditions that maintain product quality.

A competing product does not necessarily need to copy every formulation element. A developer may pursue a different antioxidant system, a different buffer approach, an oxygen-controlled manufacturing process, or a different concentration, subject to FDA requirements and patent clearance.

What patent barriers affect intravenous acetaminophen?

The original Ofirmev product had formulation-related patent protection associated with sterile intravenous acetaminophen compositions. The commercial importance of those patents has declined as product-specific exclusivity and primary patent terms have expired or approached expiration.

The current competitive barrier is more likely to arise from:

• FDA approval requirements for sterile injectable products
• Manufacturing validation
• Stability data
• Human-factor and dose-conversion controls
• Hospital purchasing agreements
• Product liability exposure
• Potential Orange Book-listed patents or certifications applicable to a specific abbreviated new drug application

A complete freedom-to-operate analysis requires review of the current FDA Orange Book, patent-family status, terminal disclaimers, maintenance fees, continuations, and litigation records. Patent expiry should not be inferred from the brand’s launch date alone.

When did Ofirmev lose exclusivity?

Ofirmev was approved by the FDA in 2010 under NDA 022450.[1] The product received the standard regulatory exclusivity associated with approval of a new active ingredient product at that time, but the relevant exclusivity periods have expired.

The commercial exclusivity timeline is:

Event	Date or status
FDA approval	November 2010
Initial U.S. brand launch	2010
New-drug exclusivity	Expired
Generic competition	Established
Current market position	Brand and generic hospital injectable market

Ofirmev no longer has a practical market position based solely on regulatory exclusivity. Its remaining commercial value depends on brand recognition, supply reliability, hospital contracts, service levels, and any enforceable formulation or process rights.

What is the Orange Book status of Ofirmev?

Ofirmev is an FDA-approved prescription drug listed in the Orange Book under acetaminophen injection. The relevant reference product is the intravenous injection at 10 mg/mL.[2]

For generic applicants, the regulatory pathway is generally an abbreviated new drug application referencing the listed drug. An applicant must address any patents listed for the reference product through the applicable certification pathway, including Paragraph III or Paragraph IV certification where relevant.

The Orange Book analysis should distinguish among:

• Listed patents that may have expired
• Patents with remaining term
• Pediatric extensions
• Product-specific exclusivity
• Method-of-use patents
• Patents not listed because they cover manufacturing or non-listable subject matter

Are Paragraph IV challenges relevant to Ofirmev?

Paragraph IV litigation risk is materially lower than it was during the product’s launch period because generic intravenous acetaminophen products are already approved and marketed. A new applicant could still face Paragraph IV issues if a relevant patent remains listed and has enforceable term.

The more important question for a new entrant is often whether the product can obtain approval without infringing formulation claims, rather than whether the reference product still has meaningful commercial exclusivity.

What generic entry opportunities exist for Ofirmev?

The generic market has several possible entry models:

Entry model	Opportunity	Main barrier
Standard 10 mg/mL vial	Direct substitution	Price competition
Ready-to-use bag	Reduced pharmacy preparation	Container cost and stability
Smaller pediatric vial	Lower waste and dosing flexibility	Manufacturing complexity
Syringe presentation	Emergency and perioperative workflow	Device and stability validation
Contract-manufactured hospital supply	Institutional tenders	Scale and service requirements
Alternative container	Differentiation and logistics	Extractables and leachables
High-throughput bulk format	Large hospital systems	Dose-error and manipulation controls

The standard 10 mg/mL injectable is the lowest-risk regulatory strategy but also the most exposed to price erosion. A differentiated presentation can command better economics if it reduces preparation time, waste, medication errors, or cold-chain requirements.

How can an excipient strategy create commercial differentiation?

Reduced oxidative degradation

A developer could optimize cysteine concentration, oxygen exposure, headspace, and container-closure performance to achieve a longer shelf life or better stability after opening. Any change must be supported by degradation-product data and validated analytical methods.

Alternative antioxidant systems

Potential alternatives include other reducing agents or oxygen-control approaches. The commercial advantage would be strongest if the alternative system:

• Improves stability
• Reduces odor or discoloration
• Simplifies manufacturing
• Reduces regulatory complexity
• Improves compatibility with the container
• Avoids an enforceable formulation claim

A substitute antioxidant is not automatically superior. It may create new concerns involving toxicity, compatibility, impurities, or insufficient stability.

Tonicity optimization

Mannitol can be adjusted within a safe and acceptable osmolality range. A lower-osmolality product may have a tolerability and labeling advantage, but the formulation must preserve solubility, stability, and infusion performance.

Low-oxygen packaging

Nitrogen purging, low-oxygen filling, improved stopper performance, and oxygen-barrier packaging can reduce the need for higher antioxidant loading. This may produce a more differentiated manufacturing patent position than a simple excipient substitution.

Pediatric and dose-efficient packaging

Ofirmev dosing is weight-based in pediatric patients. Presentations designed to minimize partial-vial waste can support hospital pharmacy economics. A 10 mL, 50 mL, or syringe format may be commercially useful depending on dose bands and institutional protocols.

Any pediatric presentation must address the risk of confusion between milligrams and milliliters. Concentration changes can create serious medication-error concerns and may reduce the commercial attractiveness of a product that requires new dosing protocols.

What FDA regulatory pathway applies to Ofirmev competitors?

A conventional generic competitor would generally use an ANDA. The product must demonstrate pharmaceutical equivalence and bioequivalence under the applicable FDA framework. For a sterile injectable, the most demanding work is often chemistry, manufacturing, and controls rather than clinical efficacy trials.

Key regulatory components include:

• Sterility assurance
• Bacterial endotoxin control
• Particulate matter testing
• Visible and subvisible particle assessment
• Assay and impurity specifications
• Stability under proposed storage conditions
• Container-closure integrity
• Extractables and leachables
• In-use and infusion compatibility
• Manufacturing-process validation
• Comparison with the reference product

A 505(b)(2) application may be relevant for a materially different presentation, concentration, delivery system, or formulation that cannot fit the ANDA pathway. The 505(b)(2) route can support product differentiation but may introduce additional clinical, labeling, or patent issues.

What manufacturing and intellectual-property barriers exist?

The primary manufacturing barrier is maintaining a stable sterile solution at commercial scale. Laboratory feasibility does not establish production robustness. Scale-up can alter oxygen transfer, mixing, hold times, filtration behavior, filling accuracy, and terminal sterilization exposure.

The strongest manufacturing IP opportunities include:

• Low-oxygen compounding and filling
• Stabilizer addition sequences
• Defined cysteine-to-acetaminophen ratios
• Improved pH-control methods
• Container-closure systems that limit oxygen ingress
• Shelf-life extension through process controls
• Reduced particulate formation
• High-throughput filling with dose-accuracy controls

Method-of-use patents are less likely to provide durable protection for the core product than formulation and manufacturing patents. A method-of-use strategy may still apply to defined perioperative protocols, opioid-sparing regimens, or pediatric use, but claim scope and enforceability require close review.

Which companies compete in the intravenous acetaminophen market?

The competitive field includes the Ofirmev brand and FDA-approved generic acetaminophen injection suppliers. Generic competition has included major injectable manufacturers and hospital-supply companies such as Fresenius Kabi, Hikma, and other approved suppliers, depending on the active product listing and market period.[3]

Competition is determined less by consumer brand awareness than by:

• Group purchasing organization contracts
• Hospital formulary placement
• Shortage performance
• Manufacturing capacity
• Contract pricing
• Product availability
• Packaging formats
• Backorder history
• Wholesaler integration

A new entrant with a conventional vial may need substantial volume to offset price compression. A product with a ready-to-administer format can pursue a different value proposition based on nursing time, pharmacy labor, and reduction of compounding steps.

What commercial opportunities exist beyond generic substitution?

The strongest opportunities are operational rather than pharmacological.

Ready-to-administer products

Hospitals may prefer bags or syringes that reduce pharmacy preparation. The value is highest in operating rooms, emergency departments, pediatric units, and institutions with centralized compounding.

Hospital shortage resilience

A supplier with redundant manufacturing, domestic capacity, and reliable inventory can win contracts even at a modest price premium. Injectable shortages have made supply continuity a purchasing criterion.

Lower-waste packaging

Smaller presentations can reduce discarded product when doses are weight-based. The benefit is most relevant in pediatric care and low-volume procedural settings.

Contract manufacturing and licensing

A formulation owner can license:

• A stabilized acetaminophen injection platform
• A low-oxygen manufacturing process
• A ready-to-use container system
• A pediatric dosing presentation
• Regional manufacturing rights
• Hospital-channel distribution rights

Licensing economics depend on whether the asset includes issued claims, regulatory data, manufacturing know-how, or only a formulation concept. Know-how and validated stability data can be commercially valuable even when broad composition claims are unavailable.

Geographic expansion

The product concept has international potential, but approval, labeling, container standards, and procurement structures vary by jurisdiction. In Europe, Canada, Japan, and emerging markets, the opportunity depends on local approval requirements, reference-product status, reimbursement, and existing paracetamol injection suppliers.

How strong is the Ofirmev patent estate?

Ofirmev’s patent estate should be characterized as historically important but commercially mature. The product’s strongest protection was linked to its intravenous formulation and stabilization technology. The present competitive moat is more dependent on regulatory compliance, manufacturing execution, and institutional purchasing than on long-dated exclusivity.

A new entrant should rank the estate across four categories:

Patent category	Current strategic value
Core composition claims	Potentially limited by expiry and design-around options
Formulation claims	Relevant if specific stabilizer and pH ranges remain enforceable
Manufacturing claims	Potentially valuable for low-oxygen and scale-up processes
Method-of-use claims	Narrower commercial relevance unless tied to a protected label

Key Takeaways

• Ofirmev is a 10 mg/mL preservative-free intravenous acetaminophen injection.
• Mannitol supports tonicity, while cysteine hydrochloride monohydrate helps control oxidative degradation.
• Core regulatory exclusivity has expired, and generic competition is established.
• The principal commercial opportunities are ready-to-use formats, pediatric packaging, lower waste, supply reliability, and pharmacy-workflow savings.
• The main technical barriers are oxidation, sterility, container compatibility, particulate control, and scale-up.
• A conventional vial is likely to face price pressure. A differentiated bag, syringe, or low-waste presentation can support better economics.
• Manufacturing and formulation patents are more commercially relevant than broad method-of-use claims.
• Orange Book and patent status must be assessed at the individual application and patent-family level before launch or licensing decisions.

FAQs

Can cysteine be removed from an Ofirmev-like formulation?

Possibly, but removal would require a different stability strategy and supporting data. The developer would need to control oxidation through packaging, oxygen reduction, alternative antioxidants, pH optimization, or a combination of these measures.

Is a premixed acetaminophen infusion more valuable than a vial?

It can be. A premixed bag may reduce pharmacy labor and manipulation, but it carries higher packaging, shipping, and stability requirements. Its value depends on hospital purchasing behavior and the cost of preparation avoided.

Can a new acetaminophen injection use a different concentration?

A different concentration may be possible, but it can trigger additional regulatory, labeling, and medication-error concerns. A concentration change may also move the product away from a straightforward ANDA strategy.

Does intravenous acetaminophen require a biosimilar pathway?

No. Acetaminophen is a small-molecule drug, not a biologic. A competing product generally follows an ANDA or, for certain differentiated products, a 505(b)(2) pathway.

What is the highest-value IP opportunity in intravenous acetaminophen?

The strongest opportunity is usually a validated manufacturing or container-closure technology that improves shelf life, reduces oxygen-related degradation, lowers waste, or enables a ready-to-administer presentation.

References

1. U.S. Food and Drug Administration. (2010). Ofirmev (acetaminophen) injection prescribing information.
2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Food and Drug Administration. (n.d.). Drugs@FDA: FDA-approved drugs, acetaminophen injection products.