List of Excipients in Branded Drug LEVOLEUCOVORIN CALCIUM

Generic Drugs Containing LEVOLEUCOVORIN CALCIUM

Company	Ingredient	NDC	Excipient
Hainan Poly Pharm Co Ltd	levoleucovorin injection	14335-340	SODIUM CHLORIDE
Hainan Poly Pharm Co Ltd	levoleucovorin injection	14335-340	SODIUM HYDROXIDE
Hainan Poly Pharm Co Ltd	levoleucovorin injection	14335-340	WATER
Amneal Pharmaceuticals LLC	levoleucovorin	70121-1572	SODIUM CHLORIDE
Amneal Pharmaceuticals LLC	levoleucovorin	70121-1572	SODIUM HYDROXIDE

What are the Most Frequently-Used Excipients in LEVOLEUCOVORIN CALCIUM?

# Of NDCs	Excipient
3	SODIUM CHLORIDE
3	SODIUM HYDROXIDE
2	WATER

Levoleucovorin Calcium Excipient Strategy and Commercial Opportunities

Last updated: August 13, 2026

Levoleucovorin calcium is a mature oncology folate product with limited active-ingredient differentiation and greater commercial potential in formulation, supply reliability, dose-convenience, and institutional economics. The strongest opportunities are preservative-free ready-to-use presentations, stable concentrated solutions, pharmacy-compounding reductions, and differentiated packaging for methotrexate rescue and fluorouracil-based chemotherapy.

What is levoleucovorin calcium used for?

Levoleucovorin calcium is the pharmacologically active l-isomer of folinic acid. It is used primarily in two settings:

1. Rescue after high-dose methotrexate.
2. Combination treatment with fluorouracil for advanced colorectal cancer and other fluorouracil-based regimens.

Unlike racemic leucovorin, levoleucovorin contains the active stereoisomer without the d-isomer. The product is administered parenterally in oncology settings, where sterility, stability, handling time, and compatibility often have greater commercial value than incremental changes to the active ingredient.

The product is a small-molecule calcium folinate formulation, not a biologic. Biosimilar approval pathways therefore do not apply. Competition is based on abbreviated new drug applications, product quality, manufacturing economics, supply continuity, and differentiated presentation.

What are the current levoleucovorin calcium dosage forms?

The principal commercial dosage form is an injectable solution or sterile injectable product for intravenous administration. The reference product Fusilev was approved by the FDA in 2008 for methotrexate rescue and in combination with fluorouracil [1].

Representative commercial presentations have included:

Product characteristic	Commercial relevance
Active ingredient	Levoleucovorin calcium
Route	Intravenous administration
Primary setting	Oncology hospitals and infusion centers
Common presentation	Single-dose vial
Preservative profile	Preservative-free products are commercially important
Packaging	Glass vial and secondary carton
Administration	Direct dilution or preparation in compatible infusion fluid
Regulatory pathway	NDA and ANDA competition
Biosimilar exposure	Not applicable

The exact strengths, vial sizes, inactive ingredients, and approved suppliers vary by product and should be assessed against current FDA labeling and DailyMed records before a launch or procurement decision [2,3].

What excipients are used in levoleucovorin calcium injections?

Levoleucovorin calcium products generally use a relatively simple excipient system. The principal formulation functions are pH control, tonicity adjustment, chemical stabilization, and protection from particulate or microbial contamination.

Typical excipient functions

Formulation function	Candidate excipient or control	Commercial purpose
pH adjustment	Hydrochloric acid and/or sodium hydroxide	Controls solubility, degradation, and injection tolerability
Tonicity	Sodium chloride, mannitol, or another compatible tonicity agent	Reduces hypotonicity and supports infusion handling
Bulking agent	Mannitol in applicable presentations	Supports lyophilized cake structure or solution tonicity
Water phase	Water for injection	Sterile vehicle
Microbial control	Aseptic processing and container closure	Supports preservative-free oncology use
Oxidation control	Low-oxygen headspace and oxygen-limiting packaging	Limits oxidative degradation
Light protection	Amber or secondary protective packaging	Reduces photochemical exposure

A commercial formulation should not assume that every listed excipient is interchangeable. The calcium salt, folate structure, pH, ionic strength, temperature, oxygen exposure, and container materials can affect stability and compatibility. Excipient selection must be confirmed through forced-degradation, extractables and leachables, particulate, sterility, endotoxin, and container-closure studies.

Which excipient risks matter most for levoleucovorin calcium?

The principal technical risk is maintaining chemical and physical stability in an aqueous sterile product over its labeled shelf life.

pH and solubility

Levoleucovorin calcium is sensitive to formulation conditions that affect solubility and degradation. Excessive alkalinity can increase degradation risk, while a low-pH environment can create solubility or compatibility problems. The commercial target is a narrow pH range that supports:

• Chemical stability.
• Acceptable injection tolerability.
• Low particulate formation.
• Compatibility with dilution fluids.
• Consistent assay and impurity control.

A formulation with fewer excipients is not automatically stronger. A small pH adjustment can have a larger effect on shelf life than adding a new stabilizer.

Oxidation

Folinates are vulnerable to degradation pathways associated with oxygen, light, heat, and reactive impurities. A practical stability program should evaluate:

• Dissolved oxygen.
• Headspace oxygen.
• Nitrogen or other inert-gas overlay.
• Light exposure.
• Metal-ion contamination.
• Rubber stopper and glass interactions.
• Agitation and shipping stress.

The strongest commercial strategy may combine a conventional excipient system with low-oxygen filling and improved container closure rather than introducing a novel antioxidant. Antioxidants can create their own regulatory and compatibility burden in an intravenous oncology product.

Container-closure interaction

Glass vials are familiar to hospital pharmacies, but the complete package system matters. Extractables from elastomeric closures, siliconization, stopper coatings, and vial surface treatments can affect impurity profiles. A supplier seeking longer dating or a ready-to-use product should treat the container closure as part of the formulation strategy.

Compatibility after dilution

The relevant stability period is not limited to the unopened vial. Hospitals may dilute levoleucovorin calcium into infusion bags or use it in treatment workflows involving fluorouracil and other oncology medicines. Product development should evaluate:

• Dilution in 0.9% sodium chloride.
• Dilution in 5% dextrose where permitted.
• Refrigerated and room-temperature hold times.
• Light exposure during preparation and administration.
• Adsorption to bags and tubing.
• Physical compatibility in pharmacy automation systems.
• Sequential or concurrent administration with fluorouracil.

Compatibility claims must be supported by product-specific data. A compatibility result for one concentration, diluent, bag, or administration set should not be generalized across the product line.

What formulation patents protect levoleucovorin calcium?

The historic intellectual-property position for levoleucovorin calcium has centered on the active stereoisomer, pharmaceutical compositions, manufacturing processes, and use in chemotherapy rather than on a broad, durable excipient platform.

The original Fusilev product was developed and commercialized by Spectrum Pharmaceuticals, later acquired by Assertio Holdings. The product’s core regulatory and commercial protection has matured, leaving conventional generic competition as the principal market constraint [1,4].

For a new entrant, potentially protectable subject matter could include:

• A defined levoleucovorin calcium concentration range.
• A low-oxygen formulation with improved impurity control.
• A specific pH and buffer-free excipient system.
• A ready-to-use product with extended in-use stability.
• A lyophilized formulation with rapid reconstitution.
• A container closure that limits oxidation or adsorption.
• A manufacturing process that reduces degradation products.
• A pharmacy workflow system tied to dose preparation or administration.

A patent based only on routine pH adjustment, standard tonicity selection, or conventional vial packaging may face obviousness and enablement challenges. Stronger protection would require comparative data showing an unexpected improvement, such as materially longer shelf life, lower degradant formation, reduced preparation time, or improved compatibility.

How many patents cover levoleucovorin calcium?

The commercially relevant question is not the historical number of patents but whether enforceable patents are currently listed or otherwise capable of delaying an entrant. FDA Orange Book listings, patent-family status, terminal disclaimers, maintenance fees, litigation history, and claim scope must be reviewed separately for each product and jurisdiction [5].

For a generic injectable, the main regulatory exposure is usually:

• Current Orange Book-listed patents, if any.
• Pediatric exclusivity or other unexpired regulatory exclusivity.
• Product-specific labeling claims.
• Manufacturing-process patents.
• Formulation patents not necessarily listed in the Orange Book.
• Patent litigation initiated after an ANDA Paragraph IV notice.

A levoleucovorin calcium product should not be treated as patent-free solely because the active ingredient is old. Conversely, the existence of historic patents does not establish a current launch block.

When does levoleucovorin calcium lose exclusivity?

Levoleucovorin calcium has already passed the period associated with new-drug market exclusivity for the original Fusilev approval. The commercial market is therefore primarily governed by generic entry, manufacturing capacity, supply contracts, and any remaining patent or regulatory barriers.

The reference-product timeline is summarized below:

Event	Timing
FDA approval of Fusilev	2008
Core small-molecule exclusivity period	Expired
Current market structure	Generic and reference-product competition
Biosimilar pathway	Not applicable
Main entry mechanism	ANDA approval
Key commercial barrier	Sterile manufacturing and reliable supply

The FDA’s current Orange Book and product-specific labeling remain the controlling sources for active listings and exclusivity status [5]. A Paragraph IV certification can create litigation risk even where the branded product has limited current sales.

What Paragraph IV challenges affect levoleucovorin calcium?

Paragraph IV risk depends on the patents identified for the reference product at the time an ANDA is filed. A generic applicant may certify that a listed patent is invalid, unenforceable, or will not be infringed. That certification can trigger patent litigation and a potential 30-month stay under the Hatch-Waxman framework [6].

For levoleucovorin calcium, the likely litigation issues would include:

• Whether a formulation patent covers the proposed inactive-ingredient system.
• Whether a proposed label falls within a patented method of use.
• Whether manufacturing claims cover the generic process.
• Whether the reference product has any currently listed patent capable of supporting a stay.
• Whether the applicant can carve out a patented indication while preserving approval for unprotected uses.

The most practical strategy for an ANDA sponsor is to minimize unnecessary overlap with branded formulation claims while preserving an economically useful label. A non-infringing formulation with equivalent clinical performance can reduce both litigation exposure and development complexity.

What excipient strategy offers the best commercial opportunity?

The highest-value strategy is a product that reduces total pharmacy cost rather than merely reproducing the reference formulation.

1. Ready-to-use injectable solution

A ready-to-use product can reduce:

• Pharmacy compounding time.
• Preparation errors.
• Need for reconstitution.
• Exposure of staff to chemotherapy workflows.
• Product waste from partial-vial dosing.

The commercial case is strongest where hospitals value standardized preparation and have high colorectal cancer or methotrexate-rescue volumes.

2. Extended in-use stability

A product with validated stability after dilution or after controlled puncture can improve pharmacy scheduling and reduce discarded doses. The claim must be narrowly tied to specified concentrations, diluents, bags, temperatures, and administration conditions.

3. High-concentration vial presentations

Higher concentration can reduce vial count and storage volume. The tradeoff is increased risk of dosing error, more demanding particulate control, and greater need for validated dilution instructions. A high-concentration product should be developed with barcoding, clear labeling, and pharmacy workflow testing.

4. Lyophilized formulation

Lyophilization can improve stability where the aqueous solution has unacceptable degradation. It may also create longer supply-chain dating. The disadvantages are reconstitution time, equipment cost, cake variability, and the risk that the hospital sees no meaningful operational advantage over a stable liquid.

5. Low-waste vial strategy

Vial sizes should reflect actual dosing patterns. Offering a small vial for low-dose methotrexate rescue and a larger vial for oncology regimens can reduce discard. The opportunity is commercial rather than purely technical and should be modeled against hospital dose distributions.

6. Premium packaging

A package with oxygen-reducing closure technology, enhanced light protection, or improved break resistance may support a differentiated product. Packaging alone is unlikely to justify a large price premium unless it creates measurable shelf-life or workflow benefits.

How does levoleucovorin calcium compare with racemic leucovorin?

Levoleucovorin calcium and racemic leucovorin compete in overlapping clinical settings, but they are not identical products.

Attribute	Levoleucovorin calcium	Racemic leucovorin
Composition	Active l-isomer	Mixture of l- and d-isomers
Clinical rationale	Provides active folate component without d-isomer	Established low-cost standard in many settings
Regulatory status	Separate drug product	Separate drug products
Generic pathway	ANDA	ANDA
Price pressure	High	Often higher volume and strong price pressure
Differentiation	Dose, convenience, supply, formulation	Cost, availability, established protocols
Substitution	Requires clinical and regulatory assessment	Cannot be assumed automatically

Levoleucovorin’s commercial advantage is not simply stereochemical purity. Hospitals may select it based on protocol, dose equivalence, formulary policy, procurement contracts, or supply conditions. A new product must establish a clear economic or operational benefit over both branded and generic calcium folinate products.

What FDA regulatory pathway applies to a new levoleucovorin calcium product?

A conventional generic injectable would generally pursue an ANDA if it can demonstrate pharmaceutical equivalence and bioequivalence under the applicable FDA requirements. The active ingredient, dosage form, route, strength, and labeling must align with the reference product, subject to permissible labeling differences [6,7].

A novel formulation may require a 505(b)(2) NDA if it relies on the safety and efficacy findings for an approved product but introduces a meaningful change, such as:

• New concentration.
• New dosage form.
• New route or administration method.
• Extended stability claim.
• New ready-to-use presentation.
• New excipient system requiring additional clinical or bridging data.

The regulatory value of a 505(b)(2) route depends on whether the formulation change supports a clinically or operationally meaningful claim. A simple excipient substitution may be easier to develop through an ANDA than through a novel-drug strategy, but the applicable pathway is product-specific.

Which companies are positioned to compete?

Competition can come from the original reference-product owner, generic injectable manufacturers, contract manufacturers, and hospital-focused specialty pharmaceutical companies. Relevant capabilities include:

• FDA-approved sterile injectable manufacturing.
• High-containment or oncology pharmacy expertise.
• Reliable glass-vial and elastomeric-closure supply.
• Injectable analytical development.
• Hospital contracting and group purchasing access.
• Ability to maintain supply during sterile manufacturing disruptions.

The competitive field is less dependent on discovery research than on manufacturing execution. A company with a lower-cost drug substance but unreliable sterile fill-finish may be less competitive than a supplier with higher manufacturing costs and dependable delivery.

What generic entry risks exist for levoleucovorin calcium?

The principal risks are operational and regulatory:

1. Sterile manufacturing failures or warning-letter exposure.
2. Shortages of vials, stoppers, or drug substance.
3. Inadequate stability after dilution.
4. Particulate or visible-inspection failures.
5. Incomplete compatibility data.
6. Labeling differences that limit protocol adoption.
7. Paragraph IV litigation.
8. Low market prices that prevent recovery of development costs.
9. Hospital resistance to a new vial size or preparation process.
10. Concentration-related medication errors.

Market entry should therefore be supported by validated supply redundancy, robust impurity methods, realistic dose-use modeling, and a hospital pharmacy value proposition.

What is the revenue opportunity for levoleucovorin calcium?

The opportunity is best characterized as a specialty injectable platform rather than a high-growth branded-drug market. Revenue potential depends on:

• Number of oncology accounts.
• Share of colorectal cancer protocols.
• Methotrexate-rescue utilization.
• Contracting with group purchasing organizations.
• Vial-size optimization.
• Shortage-driven substitution.
• Premium for ready-to-use or extended-stability products.
• Manufacturing cost per vial.
• Waste reduction relative to competing presentations.

A low-cost generic can generate volume but face limited margins. A differentiated ready-to-use or workflow-oriented product can support higher pricing, although adoption requires evidence of reduced preparation burden and acceptable total cost.

Key Takeaways

• Levoleucovorin calcium is a mature small-molecule oncology injectable with no biosimilar pathway.
• The strongest opportunities are in excipient-enabled stability, ready-to-use delivery, reduced vial waste, and pharmacy workflow improvement.
• pH, oxidation, light, container closure, and post-dilution compatibility are the central formulation issues.
• A new excipient system is commercially valuable only if it produces measurable stability, handling, or cost advantages.
• Generic entry is primarily an ANDA and sterile-manufacturing competition.
• Current Orange Book listings and product-specific patent records must control any Paragraph IV or launch analysis.
• A 505(b)(2) strategy may be appropriate for a materially differentiated concentration, dosage form, or administration presentation.
• The commercial market favors reliable supply, low waste, and simplified preparation over minor compositional changes.

FAQs

Is levoleucovorin calcium the same as leucovorin calcium?

No. Levoleucovorin calcium contains the l-isomer of folinic acid, while conventional leucovorin calcium is generally racemic. The products have overlapping uses but are separate drug products.

Can levoleucovorin calcium be formulated with preservatives?

A preservative-free formulation is generally more attractive for intravenous oncology use. Any preservative would require assessment of intravenous tolerability, compatibility, labeling, and hospital acceptance.

Is a ready-to-use levoleucovorin product patentable?

Potentially, but patent strength would depend on the specific concentration, excipient system, container closure, stability profile, and evidence of an unexpected technical benefit. Routine vial filling and conventional pH adjustment would provide weaker protection.

Can levoleucovorin calcium be combined in the same infusion bag with fluorouracil?

Compatibility cannot be presumed. The combination, sequence, concentration, diluent, container, temperature, and administration system require product-specific validation and labeling support.

Does levoleucovorin calcium qualify for a biosimilar application?

No. Levoleucovorin calcium is a chemically defined small molecule. A competing product would generally use an ANDA or, for a materially changed product, a 505(b)(2) NDA.

References

1. U.S. Food and Drug Administration. (2008). Fusilev (levoleucovorin calcium) injection: FDA approval history and prescribing information.
2. U.S. Food and Drug Administration. (n.d.). Fusilev prescribing information.
3. National Library of Medicine. (n.d.). DailyMed: Levoleucovorin calcium injection labeling.
4. Assertio Holdings, Inc. (2023). Annual report and product portfolio disclosures.
5. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book.
6. U.S. Food and Drug Administration. (2017). Abbreviated new drug application submissions: Refuse-to-receive standards.
7. U.S. Food and Drug Administration. (2023). 505(b)(2) applications.