List of Excipients in Branded Drug OXSORALEN-ULTRA

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Bausch Health US LLC	OXSORALEN-ULTRA	methoxsalen	0187-0650	1,4-SORBITAN
Bausch Health US LLC	OXSORALEN-ULTRA	methoxsalen	0187-0650	D&C YELLOW NO. 10
Bausch Health US LLC	OXSORALEN-ULTRA	methoxsalen	0187-0650	FD&C BLUE NO. 1
Bausch Health US LLC	OXSORALEN-ULTRA	methoxsalen	0187-0650	FD&C YELLOW NO. 6

Oxsoralen-Ultra Excipient Strategy and Commercial Opportunities

Last updated: August 19, 2026

Oxsoralen-Ultra is the oral 10 mg soft-gelatin formulation of methoxsalen, a photosensitizing agent used with UVA exposure in PUVA therapy. Its commercial opportunity is unlikely to come from new-molecule exclusivity. The stronger opportunities are formulation reliability, excipient-controlled photostability, softgel manufacturing, patient adherence, hospital supply, and regulatory pathways for generic or 505(b)(2) products.

The product’s core formulation constraints are narrow. Methoxsalen has low aqueous solubility, requires controlled exposure, and creates a serious phototoxicity risk when systemic exposure and UVA treatment are combined. Excipient selection therefore affects dissolution, content uniformity, light protection, capsule integrity, and pharmacokinetic consistency.

What is Oxsoralen-Ultra and how is it formulated?

Oxsoralen-Ultra contains methoxsalen, also known as 8-methoxypsoralen or 8-MOP, in a 10 mg soft-gelatin capsule. The product is administered before controlled UVA exposure in PUVA treatment. The FDA labeling identifies the product as an oral capsule and describes pharmacologic activity that depends on methoxsalen reaching the skin before UVA irradiation.[1]

What excipients are used in Oxsoralen-Ultra?

Public product labeling identifies a soft-gelatin dosage form with excipients that include gelatin, glycerin, sorbitol, titanium dioxide, and colorants. Exact excipient declarations should be taken from the current FDA-approved labeling and the commercial package insert for the relevant market and manufacturing site.[1,2]

Formulation element	Commercial function	Strategic relevance
Soft gelatin shell	Encapsulates a liquid or semisolid fill	Supports rapid release and dose uniformity
Gelatin	Structural capsule polymer	Controls shell strength, brittleness, and sealing
Glycerin	Plasticizer and humectant	Reduces shell brittleness
Sorbitol	Plasticizer or shell-conditioning agent	Affects moisture balance and capsule stability
Titanium dioxide	Opacifier and light barrier	May reduce light exposure to methoxsalen
Colorants	Product identification and light management	Supports differentiation and handling controls
Liquid fill vehicle	Solubilizes or disperses methoxsalen	Determines dissolution and bioavailability

The commercial value of the excipient system is not based on the inactive ingredients individually. It lies in the interaction between the fill vehicle, gelatin shell, capsule moisture, light exposure, dissolution profile, and manufacturing process.

Which excipient risks matter most for methoxsalen capsules?

The highest-risk attributes are photostability, fill uniformity, dissolution, shell migration, and content uniformity.

Photostability

Methoxsalen is a photoactive compound. Excessive light exposure during manufacturing, packaging, storage, or dispensing can create degradation risk or alter product quality. An opaque or strongly colored softgel shell can reduce transmission of visible and ultraviolet light. The packaging system must be assessed with the capsule, rather than treated as a separate protection measure.

Commercial opportunities include:

• Higher-performance opaque shell systems.
• Blister packaging with UV-blocking films.
• Light-protective bottles with controlled desiccant use.
• Unit-dose packaging for dermatology clinics.
• Stability-indicating specifications tied to photodegradation products.

A formulation that demonstrates stronger light protection could support a differentiated product, although the commercial value depends on whether the improvement produces a meaningful regulatory or clinical advantage.

Fill uniformity and dose control

The capsule contains only 10 mg of active ingredient. Low-dose products are sensitive to weighing error, mixing segregation, dissolution behavior, and API particle-size variation. A liquid or semisolid fill can improve dose distribution if methoxsalen is fully solubilized. A suspension fill may create greater process risk because particle settling can produce variable content unless viscosity and agitation are tightly controlled.

Critical process parameters include:

• API particle size and polymorphic form.
• Mixing time and shear.
• Fill temperature.
• Fill viscosity.
• Encapsulation speed.
• Gel mass moisture.
• Seal integrity.
• In-process weight variation.

A manufacturer seeking an ANDA or 505(b)(2) approval would need to demonstrate pharmaceutical equivalence and bioequivalence under the applicable FDA requirements. A technically elegant excipient system has limited value if it produces a difficult-to-control manufacturing process.

Dissolution and food effects

Methoxsalen’s performance may vary with the composition of the liquid fill and with gastrointestinal conditions. A solubilizing vehicle can improve dissolution but may also increase precipitation risk after dilution in gastrointestinal fluid. Surfactants, cosolvents, lipid vehicles, and self-emulsifying systems should be screened for:

• Rapid release.
• Absence of precipitation.
• Chemical stability.
• Compatibility with gelatin.
• Low oxidation potential.
• Acceptable daily excipient exposure.
• Reproducible pharmacokinetics.

A formulation change that materially alters methoxsalen exposure could increase phototoxicity risk. The target should be exposure matching, not maximum absorption.

What formulation patents protect Oxsoralen-Ultra?

The original formulation and composition patents for methoxsalen products are unlikely to provide meaningful current exclusivity because methoxsalen has been used clinically for decades and the product’s basic dosage-form technology is mature. Commercial protection is more likely to arise from process know-how, manufacturing controls, packaging design, trademarks, and regulatory execution than from active composition-of-matter patents.

Protection category	Likely current relevance
Methoxsalen composition-of-matter patents	Expired or commercially irrelevant
Original PUVA-use patents	Generally expired
Basic 10 mg capsule formulation	Likely vulnerable to generic competition
Softgel manufacturing process	Potentially protectable as know-how
Specific excipient combination	Potentially patentable, but vulnerable to obviousness and enablement challenges
Photoprotective packaging	Potentially patentable if technically differentiated
Method-of-use claims	Limited value where the treatment method is old
Trademark rights	Potentially relevant to brand positioning
Regulatory exclusivity	Generally more important for new or reformulated products than for the legacy product

A current Orange Book review should determine whether Oxsoralen-Ultra has an active listing, approved reference product status, listed patents, or exclusivity. Patent numbers and expiration dates should not be inferred from historical product availability because legacy drug listings can change after discontinuation, transfer, or withdrawal decisions.[3]

What is the FDA regulatory status of Oxsoralen-Ultra?

Oxsoralen-Ultra is an FDA-regulated prescription drug product containing methoxsalen. Its commercial status must be separated into three questions:

1. Whether the NDA remains approved.
2. Whether the product is currently marketed.
3. Whether an ANDA applicant can identify it as the reference listed drug.

FDA’s Drugs@FDA database, the Orange Book, the product label, and FDA discontinuation records are the controlling sources for those questions.[1,3,4]

A product can have an approved NDA while being unavailable commercially. It can also have limited distribution, supply interruption, or a listed discontinuation that does not automatically mean the drug was withdrawn for safety or efficacy reasons. These distinctions affect generic strategy, reference-product selection, and litigation exposure.

Can a generic company file an ANDA for Oxsoralen-Ultra?

An ANDA could be commercially attractive if FDA identifies an appropriate reference listed drug and the applicant can demonstrate pharmaceutical equivalence and bioequivalence. The main technical barriers are likely to involve the softgel dosage form, low-dose content uniformity, dissolution, and excipient comparability.

An applicant would typically evaluate:

• Same active ingredient and strength.
• Same dosage form.
• Same route of administration.
• Equivalent capsule performance.
• Equivalent labeling, subject to permissible differences.
• Bioequivalence under FDA requirements.
• Inactive-ingredient safety and suitability.
• Manufacturing-site capability for softgel production.

A liquid-filled softgel may be more difficult to reproduce than a conventional tablet or hard capsule. That difficulty can reduce the number of credible generic competitors even when patent barriers are weak.

When does Oxsoralen-Ultra lose exclusivity?

Methoxsalen’s underlying exclusivity is long expired. Any current market protection would depend on product-specific regulatory status, listed patents, approved labeling, or a later reformulation rather than on the original discovery of methoxsalen.

Paragraph IV challenge risk

If an active patent is listed for the reference product, an ANDA applicant could use a Paragraph IV certification to challenge the patent. If no unexpired patent is listed, the applicant would face less patent litigation risk but would still need to resolve regulatory and technical requirements.

Potential dispute areas include:

• Whether a listed patent claims the approved product.
• Whether a formulation claim is valid.
• Whether a process claim is infringed by the proposed manufacturing route.
• Whether a method-of-use patent is relevant to the proposed label.
• Whether a skin-phototherapy indication remains protected.
• Whether the patent is properly listable in the Orange Book.

The commercial value of a Paragraph IV strategy depends on the remaining market, the reference product’s supply position, and the probability of rapid generic substitution.

What excipient strategies could create a new Oxsoralen-Ultra product?

1. Improved light-protective softgel

A manufacturer could develop an opaque, UV-blocking capsule with validated protection against methoxsalen degradation. The product could use a light-protective blister or unit-dose pouch. This approach has the clearest link between excipient choice and the drug’s clinical risk profile.

2. Lower-variability liquid fill

A fully solubilized fill could improve dose uniformity and reduce dissolution variability relative to a suspension. The development program would need to control precipitation, oxidation, gelatin compatibility, and long-term stability.

3. Modified-release formulation

A modified-release product could have clinical value only if it improves the PUVA treatment window, reduces peak exposure, or improves tolerability. It would likely require a 505(b)(2) pathway and clinical or pharmacokinetic bridging. The commercial opportunity is larger than for a simple generic, but development risk is materially higher.

4. Pediatric or swallowability-oriented dosage form

A smaller capsule, liquid formulation, or dispersible dosage form could address patients who have difficulty swallowing capsules. Because methoxsalen dosing is tightly linked to body weight and treatment protocols, pediatric or weight-based use would require careful control of dose accuracy and phototoxicity risk.

5. Clinic-oriented packaging

Unit-dose packaging could reduce dispensing errors and improve coordination between oral dosing and UVA treatment. Packaging could incorporate:

• Dose and UVA timing instructions.
• Light-protection labeling.
• Clinic administration records.
• Tamper evidence.
• Calendar or treatment-session packaging.

Packaging alone may not support strong patent protection, but it can create a differentiated specialty-pharmacy product.

How strong is the commercial patent estate for Oxsoralen-Ultra?

The estate appears structurally weak as a legacy drug franchise unless active product-specific patents or regulatory protections remain. The stronger barriers are operational.

Barrier	Estimated commercial impact
Active composition patent	Low for legacy methoxsalen
Active formulation patent	Requires current patent and claim review
Active method-of-use patent	Potentially narrow
Softgel manufacturing know-how	Moderate
API sourcing and quality controls	Moderate
Bioequivalence complexity	Moderate to high
Photostability control	Moderate
Market size	Likely limited and specialty-focused
Brand recognition	Useful if supply is reliable
Generic substitution risk	High if an approved ANDA enters

The product is therefore more defensible as a specialized manufacturing and distribution franchise than as a conventional patent-protected brand.

What revenue exposure and market opportunities exist?

The relevant market is PUVA therapy, not the broader dermatology market. Methoxsalen competes with nonoral PUVA approaches, topical psoralen products in selected markets, narrowband UVB, excimer therapy, biologics, and systemic immunomodulators.

Potential customer segments include:

• Dermatology practices.
• Academic phototherapy centers.
• Hospital outpatient clinics.
• Specialty pharmacies.
• Patients receiving long-term PUVA.
• International markets where methoxsalen remains clinically used.

Revenue opportunities include:

1. Authorized generic supply. Compete on continuity of supply, quality, and pharmacy coverage.
2. Specialty generic. Use a robust softgel process and reliable API sourcing to reduce competitor entry.
3. 505(b)(2) reformulation. Seek a new dosage form, packaging advantage, or pharmacokinetic profile.
4. International licensing. Partner with regional manufacturers that already supply dermatology or phototherapy products.
5. Clinic packaging. Sell integrated dosing and phototherapy support without changing the active ingredient.
6. Contract manufacturing. Provide softgel production to sponsors that lack encapsulation capacity.

The principal revenue risk is limited patient volume combined with generic substitution. A differentiated product needs either a meaningful treatment advantage or a supply-chain advantage that clinics and pharmacies will pay to preserve.

Which companies are positioned to challenge or replace Oxsoralen-Ultra?

Potential challengers are likely to include:

• Generic drug companies with softgel capacity.
• Specialty dermatology manufacturers.
• Contract manufacturers with low-dose liquid-fill expertise.
• Regional pharmaceutical companies in PUVA markets.
• Sponsors pursuing 505(b)(2) phototherapy products.

Competitive analysis should focus on manufacturing capability rather than only on patent ownership. A company with an existing softgel platform, validated photostability methods, and an FDA-approved dermatology portfolio may enter faster than a company with a larger patent department but no softgel infrastructure.

What manufacturing and intellectual-property barriers affect entry?

The main manufacturing barriers are:

• Consistent solubilization or suspension of a 10 mg dose.
• Prevention of API segregation.
• Control of capsule shell moisture.
• Seal integrity during storage.
• Protection from light.
• Reproducible dissolution.
• Low batch-to-batch impurity levels.
• Qualified methoxsalen API supply.
• Stability data under commercial packaging conditions.

The main intellectual-property barriers are narrower:

• Unexpired claims covering a specific formulation.
• Claims covering a photoprotective capsule or package.
• Process claims that read on the selected softgel manufacturing route.
• Regulatory exclusivity for a later-approved reformulation.
• Trademark and trade-dress rights.

A freedom-to-operate review should cover U.S., European, Canadian, Japanese, and major emerging-market patent families. Geographic value will vary because PUVA use, generic approval standards, and methoxsalen availability differ significantly by country.

What litigation or settlement issues affect generic launch?

A generic launch could face litigation only if an unexpired, properly listed patent creates a basis for an infringement action. Settlement value would depend on remaining patent term, the size of the reference-product market, the number of expected entrants, and whether the generic sponsor has a first-filer position.

For a legacy methoxsalen product, the more probable commercial disputes concern:

• ANDA approval timing.
• Reference listed drug status.
• Product discontinuation.
• Supply interruption.
• Manufacturing-site deficiencies.
• Trademark use.
• Distribution rights.
• Contract manufacturing and licensing.

No specific current litigation or settlement should be treated as material without a verified docket, FDA record, or company disclosure.

Key Takeaways

• Oxsoralen-Ultra is a 10 mg oral methoxsalen softgel used with UVA therapy.
• Excipient value centers on photostability, dose uniformity, dissolution, shell integrity, and packaging.
• Methoxsalen’s original composition-of-matter and PUVA patents are unlikely to provide meaningful current exclusivity.
• Generic entry risk is high if an approved reference product and viable ANDA pathway remain available.
• Softgel manufacturing, low-dose control, and light protection are the most relevant technical barriers.
• The strongest commercial opportunities are specialty generic supply, improved light-protective formulations, clinic packaging, international licensing, and 505(b)(2) reformulation.
• Current Orange Book status, NDA marketing status, listed patents, and litigation must be confirmed from FDA and court records before investment or launch decisions.

FAQs

Is Oxsoralen-Ultra a tablet or a capsule?

Oxsoralen-Ultra is an oral soft-gelatin capsule containing 10 mg of methoxsalen.

Can methoxsalen be reformulated as a liquid?

Yes, but a liquid formulation would require control of dose uniformity, solubility, precipitation, stability, photoprotection, and bioequivalence or clinical bridging.

Are excipients in Oxsoralen-Ultra patent protected?

Individual excipients such as gelatin, glycerin, sorbitol, titanium dioxide, and colorants are generally established materials. Protection would depend on a specific combination, concentration range, manufacturing process, or performance claim in an unexpired patent.

Does a biosimilar pathway apply to Oxsoralen-Ultra?

No. Methoxsalen is a small-molecule drug, so biosimilar regulation is not the relevant pathway. Generic ANDA or, for a differentiated reformulation, 505(b)(2) pathways are more relevant.

What is the most attractive commercial product concept?

A light-protective, low-variability softgel supported by reliable specialty distribution is the most commercially practical concept. A modified-release or pediatric product could create greater differentiation but would require a more demanding development and regulatory program.

References

1. U.S. Food and Drug Administration. (n.d.). Oxsoralen-Ultra (methoxsalen) capsule prescribing information. Drugs@FDA.

2. U.S. National Library of Medicine. (n.d.). Methoxsalen capsule product labeling. DailyMed.

3. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations. Orange Book.

4. U.S. Food and Drug Administration. (n.d.). Drugs@FDA: FDA-approved drugs database. FDA.