List of Excipients in Branded Drug ETOMIDATE

Generic Drugs Containing ETOMIDATE

Company	Ingredient	NDC	Excipient
Hikma Pharmaceuticals USA Inc	etomidate	0143-9310	PROPYLENE GLYCOL
Hikma Pharmaceuticals USA Inc	etomidate	0143-9506	PROPYLENE GLYCOL
Heritage Pharmaceuticals Inc d/b/a Avet Pharmaceuticals Inc	etomidate	23155-160	PROPYLENE GLYCOL

What are the Most Frequently-Used Excipients in ETOMIDATE?

# Of NDCs	Excipient
18	PROPYLENE GLYCOL
9	WATER

Etomidate Excipient Strategy and Commercial Opportunities

Last updated: September 14, 2026

Etomidate is an established intravenous anesthetic with a low-cost active ingredient, broad generic availability, and limited conventional product differentiation. The strongest commercial opportunities are formulation-led: reducing injection pain, replacing propylene glycol, improving emulsion stability, enabling prefilled delivery, and developing lower-adrenal-suppression or organ-protective alternatives without changing the active pharmaceutical ingredient.

The principal formulation benchmark in the United States is etomidate injection at 2 mg/mL, commonly supplied in a propylene glycol-based vehicle. Alternative lipid-emulsion products have demonstrated that etomidate can be formulated in soybean oil, medium-chain triglycerides, egg lecithin, and glycerol, but these products create their own stability, allergy, microbial-control, and manufacturing requirements.[1-3]

What excipients are used in commercial etomidate products?

Commercial etomidate formulations use excipients primarily to solubilize the poorly water-soluble active ingredient, control tonicity, adjust pH, and support parenteral stability.

Formulation type	Typical excipient strategy	Main benefits	Main liabilities
Propylene glycol solution	Propylene glycol, water for injection, pH adjustment	Simple manufacturing, clear solution, established regulatory precedent	Injection pain, high solvent load, potential local and systemic tolerability concerns
Lipid emulsion	Soybean oil or MCT oil, egg phospholipids, glycerol, water	Lower solvent burden, potentially improved injection tolerability	Emulsion stability, oxidation, particulate control, allergen labeling, aseptic complexity
Cyclodextrin solution	Hydroxypropyl-beta-cyclodextrin or sulfobutyl ether-beta-cyclodextrin	Aqueous solubilization, potential reduction in propylene glycol	Renal safety assessment, higher excipient cost, extractables and container compatibility
Co-solvent-free nanosystem	Liposomes, polymeric nanoparticles, nanoemulsions	Potential control of tolerability and release	High development cost, complex characterization, demanding regulatory package
Ready-to-use device formulation	Existing solution or emulsion in prefilled syringe or cartridge	Faster administration, lower preparation error, differentiated workflow	Device compatibility, stability in container closure, higher unit cost

The established U.S. label for etomidate injection identifies a 2 mg/mL product using propylene glycol as the principal nonaqueous vehicle.[1] European products such as Etomidate-Lipuro use an emulsion approach containing medium-chain triglycerides, soybean oil, egg phospholipids, glycerol, and water for injection.[2]

Why is propylene glycol the main excipient target?

Propylene glycol is the most commercially important excipient issue in conventional etomidate injection. It provides solubilization at the required concentration and supports a relatively simple clear solution. Its drawbacks are injection-site discomfort, venous irritation, and the need to administer a substantial volume of nonaqueous solvent.

Etomidate itself is associated with injection pain and myoclonus. The formulation can worsen or reduce these effects depending on solvent composition, osmolality, injection rate, vein selection, and coadministration practices. A product that reduces pain without increasing preparation complexity could compete on operating-room preference even if the active ingredient remains identical.

A replacement strategy must preserve:

• Etomidate concentration, typically 2 mg/mL.
• Chemical stability during refrigerated and room-temperature storage.
• Sterility and particulate limits for intravenous injection.
• Compatibility with commonly used syringes, IV tubing, and stopcock systems.
• Rapid bolus administration.
• Comparable onset and recovery characteristics.
• Acceptable renal and hepatic excipient exposure.

The commercial value is highest when a new vehicle solves a visible clinical problem without requiring a new dosing algorithm.

What formulation patents and technical barriers apply to etomidate?

Etomidate has a mature active-ingredient history, so the most defensible intellectual-property positions are likely to arise from formulation, delivery device, manufacturing, or clinical-use claims rather than basic composition-of-matter protection.

Potential claim categories include:

1. Low-pain aqueous formulations. Claims may cover solvent ratios, pH, osmolality, buffering systems, or local-anesthetic combinations.
2. Lipid emulsions. Protection may focus on oil phase composition, phospholipid concentration, droplet size, sterilization, and physical stability.
3. Cyclodextrin complexes. Claims may cover the cyclodextrin species, drug-to-excipient ratio, concentration range, and injectable pH.
4. Preservative-free multi-dose systems. These could include container closure, aseptic filling, and in-use stability.
5. Prefilled syringes and autoinjector-style delivery. Protection may attach to viscosity, syringe materials, dose volume, needle gauge, and administration sequence.
6. Manufacturing processes. Relevant claims could cover sterile filtration, emulsion homogenization, oxygen control, lyophilization, or reconstitution.
7. Method-of-use claims. A sponsor could seek claims for reducing injection pain, limiting adrenal suppression, controlling myoclonus, or selecting etomidate for specific hemodynamic-risk populations.

The technical barrier is higher for emulsions than for propylene glycol solutions. Droplet-size distribution, creaming, coalescence, oxidation, container interaction, and sterilization can create batch-release and shelf-life challenges. For cyclodextrin products, the sponsor must establish that the complexing excipient does not create clinically important renal or tissue exposure concerns.

A patent search should distinguish expired etomidate compound patents from live formulation and device rights. The existence of an etomidate product does not establish that a particular formulation is free of third-party patent risk.

What is the FDA regulatory status of etomidate?

Etomidate is an FDA-approved intravenous general anesthetic used for induction of general anesthesia.[1] U.S. products are supplied as sterile injectable solutions, with 2 mg/mL the principal marketed strength.

Etomidate is generally regulated as a conventional small-molecule drug, not as a biologic. Biosimilar pathways therefore do not apply. Competitive entry proceeds through abbreviated new drug applications for pharmaceutically equivalent products or through a 505(b)(2) application when the proposed product relies partly on an approved reference product while introducing a clinically meaningful formulation or delivery change.

Regulatory route	Commercial use
ANDA	Conventional generic solution with the same active ingredient, strength, dosage form, route, and applicable equivalence
505(b)(2) NDA	Reformulated etomidate, lipid emulsion, novel excipient, device combination, or a product with clinical advantages requiring additional data
New NDA	Product with materially different clinical positioning or a new therapeutic claim
Combination product pathway	Prefilled syringe, cartridge, or delivery device with drug-device functionality

A reformulated etomidate product is more likely to require a 505(b)(2) strategy than a routine ANDA if it uses a different vehicle, introduces a novel excipient, changes the dose presentation, or makes claims related to tolerability or clinical outcomes.

What is the Orange Book status of etomidate?

The commercial significance of Orange Book listings for etomidate is limited compared with newer branded anesthetics. The active ingredient has been available for decades, and routine generic products compete primarily on supply reliability, price, packaging, and hospital contracting.

A prospective entrant must still review:

• Reference listed drug status.
• Current patent and exclusivity listings.
• Paragraph IV certifications for any listed patents.
• FDA product-specific guidance.
• Discontinued-product and availability records.
• Drug shortage history.
• Whether a proposed formulation is pharmaceutically equivalent to the reference product.

For an established generic injectable, the greater barrier is often regulatory and manufacturing execution rather than a blocking active-ingredient patent. Injectable products require validated aseptic processing, strong container-closure controls, tight particulate specifications, and reliable supply of sterile components.

When does etomidate lose exclusivity, and what does that mean for generic entry?

The original etomidate exclusivity period has long expired. Generic entry is therefore commercially feasible, and the market does not depend on an upcoming loss-of-exclusivity event.

A generic etomidate solution can usually compete through:

• Lower acquisition cost.
• Reliable hospital supply.
• Vial and carton configuration.
• 2 mg/mL dose availability.
• Compatibility with automated dispensing systems.
• Contract manufacturing and group-purchasing organization access.

A differentiated formulation cannot rely on ordinary generic substitution if it changes the vehicle, presentation, or clinical claims. Its commercial opportunity depends on obtaining a distinct product profile and persuading hospitals to pay for reduced pain, lower solvent exposure, simpler administration, or reduced waste.

What commercial opportunities exist for etomidate excipient innovation?

1. Propylene glycol reduction

A lower-propylene-glycol formulation is the clearest opportunity. The product could retain the established 2 mg/mL dose while reducing solvent-associated discomfort and improving tolerability. The commercial case would require head-to-head evidence against the conventional solution.

2. Lipid-emulsion etomidate

Lipid emulsions have the strongest precedent for avoiding a high co-solvent load. A modern emulsion could use a controlled oil phase, smaller droplet size, antioxidant protection, and a preservative-free single-dose package.

The main commercial risks are greater manufacturing cost, emulsion instability, microbial-control requirements, and potential concerns for patients with egg or soybean hypersensitivity. The label would need clear handling and compatibility instructions.

3. Ready-to-use prefilled syringes

Operating-room staff value products that reduce preparation time and dosing error. A prefilled etomidate syringe could be sold at a premium if it offers:

• Accurate unit dosing.
• Reduced vial manipulation.
• Improved labeling visibility.
• Lower waste.
• Compatibility with anesthesia workflows.
• Stable storage without refrigeration, if achievable.

The device, however, must not create adsorption, leachables, stopper fragmentation, or dose-delivery problems.

4. Pediatric and emergency-use presentations

Etomidate is used in emergency airway management and anesthesia induction. Smaller-volume, clearly labeled presentations could target emergency departments, ambulances, intensive-care units, and pediatric anesthesia.

Commercially useful formats include unit-dose syringes, small-volume vials, and barcoded packages compatible with medication cabinets. The product would compete on readiness and error reduction rather than active-ingredient novelty.

5. Combination approaches for injection pain

A sponsor could investigate local anesthetic coformulation or premedication strategies. A fixed combination faces substantial regulatory and safety complexity because the second agent may affect cardiovascular function, neurologic assessment, or dosing flexibility.

A more practical approach may be a packaged administration system with an anesthetic adjunct supplied separately. That reduces formulation complexity but may provide weaker patent protection.

6. Hospital supply resilience

Etomidate has commercial value as a supply-reliability product. Hospitals may favor manufacturers that maintain dual-source excipient supply, domestic sterile filling, multiple vial sizes, and shortage-response capacity. A robust supply chain can be a stronger purchasing advantage than a modest formulation improvement.

How does etomidate compare with competing induction agents?

Etomidate competes with propofol, ketamine, and barbiturates. Its principal perceived advantage is relative cardiovascular stability during induction, while its important disadvantages include adrenal suppression, myoclonus, and injection pain.[4-6]

Product	Excipient opportunity	Key competitive issue
Etomidate	Replace propylene glycol; improve injection tolerability; prefilled delivery	Adrenal suppression and myoclonus
Propofol	Lipid-emulsion stability, antimicrobial control, packaging	Hypotension, pain, strict handling requirements
Ketamine	Concentration, preservative, nasal or injectable delivery	Psychotomimetic effects and workflow preferences
Thiopental	Reconstitution and stability	Limited modern use and supply constraints

An etomidate formulation that reduces injection pain and myoclonus while preserving hemodynamic performance could gain share in emergency and high-risk induction settings. It would not eliminate clinical debate over adrenal suppression, which remains a central limitation of the molecule.[4,5]

Which companies are challenging the etomidate market?

The market is primarily contested by generic injectable manufacturers, hospital-supply companies, and specialty pharmaceutical firms with sterile manufacturing capacity. Competition is usually based on price, availability, packaging, and contract coverage rather than branded promotion.

The most credible entrants are companies with:

• FDA-compliant sterile injectable facilities.
• Access to propylene glycol, lipid excipients, or cyclodextrins at pharmaceutical grade.
• Experience with aseptic filling and terminal or sterile filtration processes.
• Hospital and group-purchasing distribution.
• Capability to support a 505(b)(2) development program.
• Established pharmacovigilance and shortage-management systems.

A startup without sterile manufacturing infrastructure would likely need a contract development and manufacturing organization or a licensing partner.

What licensing deals and partnership structures are most practical?

The likely transaction model is a formulation license or co-development agreement rather than a license for the etomidate molecule. Attractive deal assets include:

• A validated low-pain formulation.
• A stable lipid-emulsion platform.
• A patent-protected prefilled syringe.
• A 505(b)(2)-ready development package.
• A manufacturing process that uses standard sterile equipment.
• Clinical data showing lower injection pain or improved workflow.

Royalty value depends on clinical differentiation and patent term. A formulation that only reduces manufacturing cost is more likely to support a supply agreement than a high-value commercial license. A product with human tolerability data, strong freedom-to-operate analysis, and a clear FDA pathway has greater partnering leverage.

What generic launch risks exist for a new etomidate formulation?

The principal risks are:

1. Clinical differentiation risk. Lower solvent exposure may not produce a sufficiently meaningful patient or workflow benefit.
2. Regulatory risk. A novel excipient or altered dosage form can expand nonclinical and clinical requirements.
3. Manufacturing risk. Emulsions and complex delivery systems have higher failure rates than clear solutions.
4. Commercial substitution risk. Hospitals may select the lowest-cost generic unless the product reduces labor, waste, or adverse events.
5. Patent risk. Formulation and device claims may be crowded even when compound patents are expired.
6. Supply risk. Sterile injectable shortages can create opportunity, but they also expose manufacturers to scrutiny and rapid demand changes.
7. Competitive risk. Propofol and ketamine remain entrenched alternatives with established emergency and anesthesia workflows.

Key Takeaways

• Etomidate is a mature generic anesthetic with limited active-ingredient exclusivity value.
• Propylene glycol is the principal excipient target because of injection pain and solvent burden.
• Lipid emulsions, cyclodextrin systems, and prefilled syringes offer the clearest formulation-led opportunities.
• A reformulated product would likely require a 505(b)(2) strategy rather than a routine ANDA.
• Biosimilar risk is irrelevant because etomidate is a conventional small molecule.
• The commercial case depends on measurable reductions in pain, preparation burden, waste, or supply risk.
• The strongest assets combine human tolerability data, defensible formulation patents, sterile manufacturing capability, and hospital distribution.
• Generic entry risk is high for conventional 2 mg/mL solutions and lower for differentiated delivery systems with credible clinical advantages.

FAQs

Can etomidate be formulated without propylene glycol?

Yes. Lipid emulsions and complexation approaches can replace or reduce propylene glycol. The formulation must meet injectable stability, sterility, compatibility, and safety requirements.

Is Etomidate-Lipuro available in the United States?

Etomidate-Lipuro is associated primarily with markets outside the United States. U.S. commercial availability depends on the specific FDA-approved product and manufacturer.[2]

Does etomidate have biosimilar competition?

No. Etomidate is a small-molecule drug. Competition occurs through generic drug applications and, for differentiated formulations, potentially through the 505(b)(2) pathway.

What is the most valuable patent strategy for etomidate?

The strongest strategy is likely a layered portfolio covering formulation composition, manufacturing process, container closure, prefilled delivery, and clinically supported tolerability or administration claims.

Can a prefilled etomidate syringe command a premium price?

Potentially. The premium must be supported by reduced preparation time, lower dosing error, lower waste, improved inventory control, or documented workflow benefits. A packaging change alone is unlikely to support a large premium.

References

1. U.S. Food and Drug Administration. (n.d.). Etomidate injection, USP: Prescribing information. DailyMed.
2. B. Braun Melsungen AG. (n.d.). Etomidate-Lipuro 2 mg/mL emulsion for injection: Summary of product characteristics.
3. U.S. Food and Drug Administration. (2017). Inactive ingredient database.
4. Forman, S. A. (2011). Clinical and molecular pharmacology of etomidate. Anesthesiology, 114(3), 695-707.
5. Zhang, G. H., Sun, L., & Sinha, A. (2019). Etomidate and adrenal suppression: A review of the clinical evidence. Journal of Clinical Anesthesia, 55, 56-62.
6. U.S. Food and Drug Administration. (n.d.). Orange Book: Approved drug products with therapeutic equivalence evaluations. FDA.