List of Excipients in Branded Drug SIGNATURE CARE NAPROXEN SODIUM PM

Generic Drugs Containing SIGNATURE CARE NAPROXEN SODIUM PM

Company	Ingredient	NDC	Excipient
Safeway	diphenhydramine hydrochloride, naproxen sodium	21130-808	CELLULOSE, MICROCRYSTALLINE
Safeway	diphenhydramine hydrochloride, naproxen sodium	21130-808	CROSCARMELLOSE SODIUM
Safeway	diphenhydramine hydrochloride, naproxen sodium	21130-808	FD&C BLUE NO. 1
Safeway	diphenhydramine hydrochloride, naproxen sodium	21130-808	FD&C BLUE NO. 2

What are the Most Frequently-Used Excipients in SIGNATURE CARE NAPROXEN SODIUM PM?

# Of NDCs	Excipient
1	CELLULOSE, MICROCRYSTALLINE
1	CROSCARMELLOSE SODIUM
1	FD&C BLUE NO. 1
1	FD&C BLUE NO. 2

SIGNATURE CARE NAPROXEN SODIUM PM: Excipient Strategy, Patent Position, and Commercial Opportunities

Last updated: August 5, 2026

Signature Care Naproxen Sodium PM is a private-label nighttime analgesic combining naproxen sodium, an NSAID, with diphenhydramine, a sedating antihistamine used as a nighttime sleep aid. The commercial opportunity is primarily in cost-efficient immediate-release manufacturing, differentiated package sizes, retailer exclusivity, and line extensions rather than active-ingredient exclusivity. The core drug substances are long-established, and the basic product has limited patent protection.

What is Signature Care Naproxen Sodium PM?

Signature Care Naproxen Sodium PM is positioned as an OTC nighttime pain-relief product. The reference product category generally contains:

Component	Typical strength	Function
Naproxen sodium	220 mg	NSAID analgesic and antipyretic
Diphenhydramine hydrochloride	25 mg	Nighttime sleep-aid component

Naproxen sodium is the sodium salt of naproxen. The salt improves aqueous dissolution relative to the free acid and supports immediate-release tablet manufacturing. Diphenhydramine hydrochloride is highly established in OTC sleep-aid products and is generally used at a 25 mg bedtime dose.

The product competes with Aleve PM and store-brand equivalents. Its principal value proposition is convenience: one dose for nighttime pain and temporary sleeplessness associated with minor aches and pains.

What excipients are likely used in Naproxen Sodium PM tablets?

The most commercially practical dosage form is a film-coated immediate-release caplet. A typical formulation requires excipients for compression, disintegration, lubrication, coating, color, and moisture control.

Core tablet excipient strategy

Formulation function	Suitable excipient classes	Commercial purpose
Diluent	Microcrystalline cellulose, lactose, dibasic calcium phosphate	Provides tablet mass and compression performance
Binder	Povidone, pregelatinized starch, hydroxypropyl cellulose	Improves granule and tablet strength
Disintegrant	Croscarmellose sodium, crospovidone, sodium starch glycolate	Promotes rapid tablet breakup
Lubricant	Magnesium stearate, sodium stearyl fumarate	Supports ejection and high-speed compression
Glidant	Colloidal silicon dioxide	Improves powder flow
Surfactant or wetting aid	Sodium lauryl sulfate or equivalent	Supports wetting and dissolution
Film coating	Hypromellose, polyethylene glycol, titanium dioxide, approved colorants	Improves swallowability, appearance, and handling
Opacifier	Titanium dioxide or alternative opacifier	Controls light exposure and appearance

The primary excipient objective is rapid and reproducible dissolution for both actives. The formulation should avoid excessive hydrophobic lubrication, which can slow wetting and dissolution. Magnesium stearate concentration and blending time require tight control because over-lubrication can reduce tablet strength and delay release.

Naproxen sodium compatibility considerations

Naproxen sodium is sensitive to formulation conditions that affect dissolution and stability. A high-solids, direct-compression or dry-granulation process can reduce exposure to water during manufacturing. This can lower processing complexity and help control degradation.

Microcrystalline cellulose and crospovidone are commercially attractive because they support robust direct compression and fast disintegration. Croscarmellose sodium is also suitable, although its performance depends on grade, particle size, and compression force.

The formulation should maintain consistent pH and moisture conditions. Excessive water exposure during wet granulation can complicate stability work and increase drying requirements. A low-moisture process is generally preferable unless the manufacturer has a validated wet-granulation platform.

Diphenhydramine compatibility considerations

Diphenhydramine hydrochloride can contribute to powder-flow and content-uniformity challenges because the active dose is substantially lower than the naproxen sodium load. Geometric dilution, ordered mixing, or granulation may be needed to distribute diphenhydramine consistently.

A formulation should avoid excessive segregation between the two actives and the excipient blend. Particle-size matching, controlled addition of the lower-dose active, and in-process blend-uniformity testing are important commercial controls.

What formulation patents protect Naproxen Sodium PM products?

The basic naproxen sodium and diphenhydramine combination has limited composition-of-matter protection. Naproxen patents and diphenhydramine patents expired long ago. A conventional immediate-release caplet using established excipients is unlikely to create a material blocking patent position by itself.

Potentially relevant patent categories include:

1. Fixed-dose combinations of naproxen sodium and diphenhydramine.
2. Modified-release or multilayer tablets.
3. Specific dissolution profiles.
4. Taste-masked or rapidly disintegrating formulations.
5. Abuse-deterrent or tamper-resistant packaging.
6. Novel coating systems.
7. Manufacturing processes that improve content uniformity or stability.
8. Pediatric, liquid, chewable, or orally disintegrating presentations.

A conventional private-label product should be analyzed primarily for freedom to operate around formulation and packaging claims. The active ingredients do not create a meaningful new-molecule exclusivity barrier.

What is the Orange Book status of Signature Care Naproxen Sodium PM?

Signature Care Naproxen Sodium PM is an OTC private-label product, not a conventional prescription product with an extensive Orange Book patent estate. The Orange Book is principally relevant to approved prescription and certain approved OTC applications. OTC products can be marketed under an FDA-approved application or under an applicable OTC monograph framework, depending on the product and manufacturer.

The commercial diligence question is whether the specific product is marketed under:

• An OTC monograph or final monograph order.
• An abbreviated application referencing an approved OTC product.
• A product-specific NDA or other FDA application.
• A private-label agreement involving an authorized manufacturer.

The public Drug Facts label establishes active ingredients, directions, warnings, and certain inactive ingredients, but it does not by itself establish the full regulatory or contractual relationship between a store brand and its manufacturer. FDA OTC monograph requirements for internal analgesics and nighttime sleep-aid products are relevant to the active ingredients and labeling framework. [1,2]

When does Naproxen Sodium PM lose exclusivity?

The product has no meaningful new-drug exclusivity timeline comparable to a patented prescription medicine. Market exclusivity is principally commercial and contractual.

Exclusivity source	Relevance to Signature Care
New chemical entity exclusivity	Not applicable to established naproxen or diphenhydramine
Patent exclusivity	Low for a conventional immediate-release product
Pediatric exclusivity	Not a central product driver
OTC monograph protection	Regulatory compliance framework, not brand exclusivity
Retailer contract	Potential short-term private-label differentiation
Manufacturing agreement	May restrict supplier access or formulation copying
Trademark protection	Protects the Signature Care brand, not the formulation

Generic or private-label entry is therefore possible if a manufacturer can satisfy FDA requirements, reproduce the target product profile, and obtain retail distribution.

How strong is the patent estate for Signature Care Naproxen Sodium PM?

The patent estate is likely weak for the base product and stronger only for engineered variants.

Patent-strength assessment

Patent category	Likely strength	Commercial assessment
Naproxen sodium active ingredient	Very low	Long-established active
Diphenhydramine active ingredient	Very low	Long-established OTC ingredient
Conventional immediate-release tablet	Low	Common excipient and process technology
Specific fixed-dose combination	Low to moderate	Depends on claim scope and prior art
Modified release	Moderate	Requires technical differentiation
Novel coating or taste masking	Moderate	May support secondary patents
Manufacturing process	Moderate	Useful if it creates measurable quality or cost advantages
Packaging and child resistance	Low to moderate	Often protectable only in narrow configurations

A patent filing would have stronger commercial value if it claimed a measurable technical result, such as faster dissolution after storage, improved content uniformity, reduced tablet weight, lower friability, or improved stability under accelerated conditions. Broad claims covering the mere combination of two old OTC actives would face substantial prior-art risk.

What FDA regulatory issues affect this product?

The product must satisfy FDA requirements for both the analgesic and nighttime sleep-aid components. Naproxen carries NSAID-related warnings involving gastrointestinal bleeding, cardiovascular risk, allergic reactions, and use with other NSAIDs. Diphenhydramine carries warnings concerning drowsiness, alcohol, driving, sedatives, and use by certain populations.

The main regulatory risks are:

• Inadequate combination-product labeling.
• Inconsistent directions between analgesic and sleep-aid dosing.
• Failure to identify duplicate NSAID exposure.
• Inadequate warnings about alcohol and sedatives.
• Unsupported claims such as "non-drowsy," "long-lasting sleep," or "stronger pain relief."
• Dissolution or stability failures after scale-up.
• Inactive-ingredient changes that affect product quality or appearance.
• Manufacturing-site or private-label documentation gaps.

The FDA Drug Facts format requires clear disclosure of active ingredients, purposes, uses, warnings, directions, and inactive ingredients. [3]

What commercial opportunities exist for excipient optimization?

Lower-cost direct compression

The most immediate opportunity is a direct-compression platform using microcrystalline cellulose, a high-performance disintegrant, colloidal silicon dioxide, and magnesium stearate. This approach can reduce solvent handling, drying capacity, and cycle time.

The main development targets are:

• Shorter blend and compression cycles.
• Lower tablet weight.
• Reduced friability.
• Consistent disintegration across production scale.
• Stable dissolution after accelerated storage.

Coating and appearance differentiation

Store-brand products can use color, imprint, and coating changes to create retailer-specific SKUs without changing the therapeutic profile. A thin hypromellose-based coating can improve swallowability and reduce powdering during packaging.

Color selection should account for:

• Retailer appearance requirements.
• Colorant availability.
• Light stability.
• Consumer recognition.
• Potential reformulation pressure around titanium dioxide or other pigments.

Packaging-based opportunities

Packaging can create more practical differentiation than the tablet itself. Potential formats include:

• Two-count travel packs.
• Ten-count blister packs.
• Twenty-count and forty-count bottles.
• Unit-dose nighttime blister cards.
• Senior-friendly bottles with larger labels.
• Child-resistant, unit-dose cartons.
• E-commerce multipacks.

Unit-dose packaging can improve portability and dose control, although it increases packaging cost. Bottles remain more competitive for high-volume store-brand distribution.

Line extensions

The strongest extensions are adjacent presentations rather than new active combinations:

Extension	Opportunity
Naproxen sodium daytime product	Separates analgesic demand from nighttime sedation
Smaller-count travel pack	Supports convenience and trial
Liquid or softgel format	May reach consumers who avoid caplets
Higher-count value pack	Supports household use and retailer margin
Alcohol-free nighttime positioning	Label and marketing refinement
Senior-focused packaging	Improves usability without changing actives

A softgel can offer swallowing and perceived onset advantages, but it carries higher manufacturing and packaging costs. It may also require a separate formulation and stability program.

Which companies are challenging the product category?

The category is challenged by store brands, generic OTC manufacturers, and established branded products. Relevant competitive groups include:

• Bayer, through Aleve and Aleve PM.
• Perrigo, as a major OTC private-label and store-brand supplier.
• Kenvue, through competing analgesic and nighttime products.
• Retailer-owned brands such as Walgreens, CVS, Walmart, Target, and supermarket private labels.
• Contract manufacturers supplying regional pharmacy and grocery chains.

Competition is based on retail price, count size, shelf placement, packaging, retailer margin, and supply reliability. The active ingredients are broadly available, so manufacturing capacity and retailer access matter more than molecule ownership.

What generic entry risks exist for Signature Care Naproxen Sodium PM?

Generic and private-label entry risk is high for a conventional immediate-release product. The principal barriers are operational rather than patent-based:

1. FDA-compliant formulation and labeling.
2. Demonstrated dissolution and stability.
3. Reliable supply of both active ingredients.
4. Consistent content uniformity for diphenhydramine.
5. Retailer qualification and quality audits.
6. Child-resistant packaging compliance.
7. Product-liability controls.
8. Competitive cost per dose.

A competitor could launch a substantially equivalent product without overcoming a strong active-ingredient patent. Differentiation therefore depends on supply agreements, packaging, retailer exclusivity, and manufacturing economics.

What patent litigation or Paragraph IV risk affects the product?

Paragraph IV litigation is generally associated with an abbreviated application challenging patents listed for an approved reference drug. A conventional OTC private-label product has lower Paragraph IV exposure than a patented prescription product.

Risk could increase if the product references an approved OTC combination with listed patents covering:

• A specific fixed-dose combination.
• Modified release.
• A particular coating or dosage form.
• A novel manufacturing process.
• A product-specific method of use.

For the standard immediate-release naproxen sodium and diphenhydramine category, the more likely disputes involve trademark, label copying, contract manufacturing, trade dress, or retailer supply agreements rather than major patent litigation.

How does Naproxen Sodium PM compare with Aleve PM?

Factor	Signature Care Naproxen Sodium PM	Aleve PM
Brand position	Store brand	National brand
Active ingredients	Typically naproxen sodium and diphenhydramine	Naproxen sodium and diphenhydramine
Price	Usually lower	Usually higher
Patent value	Limited for conventional product	Brand and product-specific rights may be more relevant
Retail access	Dependent on retailer ownership	Broad branded distribution
Differentiation	Price, count, packaging	Brand recognition and marketing
Generic substitution risk	High	High at the ingredient level
Margin strategy	Retailer and supplier efficiency	Brand premium and promotion

The private-label product can compete effectively when it matches the reference product's tablet appearance, directions, pack size, and availability while maintaining a lower retail price.

What licensing and manufacturing deals matter?

The most relevant commercial agreements are private-label supply and licensing arrangements. These may cover:

• Use of a retailer trademark.
• Exclusive supply by geography or channel.
• Product-specific formulation ownership.
• Artwork and packaging rights.
• Regulatory responsibility.
• Pharmacovigilance and complaint handling.
• Minimum purchase volumes.
• Manufacturing-site approval.
• Product discontinuation and change-control procedures.

A supplier with an existing NSAID and antihistamine platform can reduce development cost by reusing validated excipient systems, compression tooling, coating equipment, and packaging lines. The commercial value of a formulation license is highest when it solves a documented manufacturing problem, such as low-dose content uniformity or accelerated-stability failure.

Key Takeaways

• Signature Care Naproxen Sodium PM is a private-label OTC nighttime analgesic category built around naproxen sodium and diphenhydramine.
• Conventional immediate-release products have limited active-ingredient and formulation patent protection.
• Excipient optimization should prioritize fast dissolution, low moisture exposure, content uniformity, and high-speed compression.
• Microcrystalline cellulose, crospovidone or croscarmellose sodium, colloidal silicon dioxide, and controlled magnesium stearate use are practical platform choices.
• The largest commercial opportunities are retailer exclusivity, lower-cost direct compression, travel packs, unit-dose packaging, and value-count extensions.
• Generic entry risk is high because the key barriers are regulatory execution, manufacturing quality, supply, and retail access.
• Product-specific FDA pathway and patent diligence should focus on the actual manufacturer, NDC, reference product, and contractual supply structure.

FAQs

Is naproxen sodium PM protected by a new chemical entity patent?

No. Naproxen sodium and diphenhydramine are established OTC active ingredients. Any meaningful patent value would need to arise from a specific formulation, process, delivery system, or packaging configuration.

Can a manufacturer use the same excipients as Signature Care?

A manufacturer can generally use the same common excipient classes, but it cannot copy protected trade dress, trademarks, proprietary specifications, or confidential manufacturing information. The finished product must independently satisfy FDA quality and labeling requirements.

Is diphenhydramine necessary in a nighttime naproxen product?

Diphenhydramine provides the nighttime sleep-aid positioning. Removing it would create a conventional naproxen product rather than a PM combination and would require different labeling, positioning, and competitive analysis.

Which excipient provides the greatest commercial differentiation?

No single common excipient is likely to create strong differentiation. The highest value usually comes from the combined formulation process, including rapid disintegration, dissolution stability, tablet robustness, coating performance, and low-cost manufacturability.

What is the best private-label format for this product?

A film-coated immediate-release caplet in a 20-count or 40-count child-resistant bottle is the most conventional mass-market format. Two-count and ten-count blister packs provide stronger convenience differentiation but generally carry higher packaging costs.

References

1. U.S. Food and Drug Administration. (n.d.). OTC Monograph M005: Internal analgesic, antipyretic, and antirheumatic drug products. https://www.accessdata.fda.gov
2. U.S. Food and Drug Administration. (n.d.). OTC Monograph M010: Nighttime sleep-aid drug products. https://www.accessdata.fda.gov
3. U.S. Food and Drug Administration. (2023). Over-the-counter drug product labeling. https://www.fda.gov/drugs/drug-approvals-and-databases/otc-drug-monograph-reform
4. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. U.S. Department of Health and Human Services. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
5. DailyMed. (n.d.). Naproxen sodium and diphenhydramine hydrochloride product labeling. National Library of Medicine. https://dailymed.nlm.nih.gov