Last updated: September 1, 2026
Sodium phosphate, monobasic, anhydrous is a mature, low-cost pharmaceutical excipient with demand linked to oral solid dosage manufacturing, pH control, buffering, tonicity adjustment, analytical production, and selected biologic formulations. Its commercial profile is driven by volume, qualification status, regional manufacturing capacity, and supply reliability rather than proprietary technology or patent exclusivity.
The product is also known as anhydrous sodium dihydrogen phosphate, sodium phosphate monobasic anhydrous, and sodium dihydrogen orthophosphate. Its CAS Registry Number is 7558-80-7. The compound is distinct from sodium phosphate, monobasic, monohydrate, CAS 10049-21-5, which has different water content, molecular weight, storage characteristics, and formulation behavior [1].
What is the pharmaceutical market for sodium phosphate, monobasic, anhydrous?
The market is a fragmented segment of the broader pharmaceutical excipients industry. Public company filings generally combine sodium phosphate products with broader phosphate, inorganic salt, buffer, or pharmaceutical ingredient categories. Standalone global revenue for anhydrous sodium phosphate monobasic is not separately disclosed by major manufacturers.
| Market characteristic |
Assessment |
| Product type |
Inorganic pharmaceutical excipient and process material |
| Chemical formula |
NaH2PO4 |
| CAS number |
7558-80-7 |
| Primary functions |
Buffering, pH adjustment, tonicity control, formulation aid |
| Principal dosage forms |
Tablets, capsules, oral powders, solutions, and selected parenteral formulations |
| Market structure |
Fragmented, with global distributors and regional manufacturers |
| Pricing power |
Low to moderate |
| Patent protection |
Generally none for the commodity compound |
| Primary barriers |
Pharmacopeial compliance, impurity control, validation, audit history, and supply continuity |
| Main commercial risk |
Substitution by the monohydrate or other phosphate buffers |
Demand is relatively stable because the compound is used in established formulations and manufacturing processes. Growth is tied to pharmaceutical production volumes, generic drug launches, contract manufacturing, and formulation outsourcing.
The product does not have the growth profile of high-value functional excipients such as lipid nanoparticles, advanced polymers, or specialized biologic stabilizers. Its revenue trajectory is more likely to track pharmaceutical volume growth, inflation, and mix changes than innovation premiums.
What applications drive demand for anhydrous sodium phosphate?
Anhydrous sodium phosphate monobasic is used primarily as a buffer component and pH modifier. It is often paired with dibasic sodium phosphate to create phosphate-buffer systems across a defined pH range.
Pharmaceutical formulations
The compound can be used in:
- Immediate-release and modified-release tablets
- Capsules and powder blends
- Oral liquid formulations
- Reconstituted products
- Ophthalmic and topical preparations
- Selected injectable and biologic formulations
- Laboratory and manufacturing buffers
The specific grade, particle-size distribution, residual moisture, elemental impurities, microbial limits, and endotoxin profile depend on the dosage form. Injectable and ophthalmic applications normally impose more stringent controls than conventional oral solid dosage products.
Biologics and biosimilar manufacturing
Sodium phosphate buffers are used in some biologic drug products and process solutions, but the compound is not a biosimilar-specific excipient. Biosimilar approvals can increase demand for qualified buffer materials through greater manufacturing volume, new fill-finish capacity, and process standardization.
The product is not exposed to biosimilar patent litigation in the way an originator biologic is. Its commercial exposure is indirect and depends on the scale of biologic production, formulation choice, and customer qualification.
Non-pharmaceutical demand
Industrial, food, laboratory, and water-treatment applications can account for significant phosphate demand, but these markets generally use different grades and have lower qualification requirements. Pharmaceutical-grade demand is more defensible because switching suppliers requires documentation, testing, quality agreements, and regulatory change control.
How does anhydrous sodium phosphate compare with the monohydrate?
The primary commercial substitute is sodium phosphate, monobasic, monohydrate. The two materials provide the same phosphate functionality but differ in water content and physical properties.
| Attribute |
Anhydrous form |
Monohydrate form |
| Chemical identity |
NaH2PO4 |
NaH2PO4·H2O |
| CAS number |
7558-80-7 |
10049-21-5 |
| Water of crystallization |
None by stoichiometry |
One molecule per molecule |
| Molecular weight |
Approximately 119.98 g/mol |
Approximately 137.99 g/mol |
| Formulation impact |
Higher active salt content by weight |
Lower salt content by weight |
| Main advantage |
Lower water contribution and higher molar concentration per unit mass |
Often easier to source and handle in established formulations |
| Main risk |
Hygroscopicity, phase control, and supplier-specific physical variation |
Moisture contribution and different assay calculations |
| Switching requirements |
Recalculation, stability review, and validation |
Recalculation, stability review, and validation |
A formulation cannot generally substitute one form for the other on a one-to-one weight basis. A change requires molar conversion, reassessment of water activity, dissolution behavior, blend uniformity, stability, and packaging.
The existence of a qualified monohydrate alternative limits pricing power for the anhydrous product. Suppliers can defend share when customers require anhydrous material for moisture-sensitive formulations or validated processes.
What companies supply pharmaceutical-grade sodium phosphate, monobasic, anhydrous?
Supply is distributed across large chemical companies, pharmaceutical raw-material specialists, and regional producers. Common commercial channels include:
- Merck and Sigma-Aldrich
- Avantor and J.T.Baker
- Thermo Fisher Scientific and related laboratory-supply channels
- Spectrum Chemical
- Jost Chemical
- Finar and other regional pharmaceutical-ingredient suppliers
- Chinese and Indian inorganic-salt manufacturers
- Contract and distributor networks serving Europe, North America, and Asia
Supplier presence varies by grade and region. A catalog listing does not establish that a product is suitable for a regulated pharmaceutical formulation. Buyers normally distinguish among ACS, laboratory, food, USP-NF, Ph. Eur., BP, and customer-specific pharmaceutical grades.
What determines supplier selection?
The principal selection criteria are:
- Current pharmacopeial compliance
- Certificate-of-analysis consistency
- Elemental impurity control
- Residual moisture and loss-on-drying performance
- Particle-size and flow characteristics
- Manufacturing-site qualification
- Change-notification controls
- Audit history and quality agreements
- Regional inventory
- Dual-source availability
For high-volume oral formulations, price and continuity dominate. For sterile or biologic applications, documentation and impurity control carry greater weight than nominal purchase price.
How strong is the patent estate for sodium phosphate, monobasic, anhydrous?
The compound has no meaningful composition-of-matter patent estate. Sodium phosphate monobasic is an old inorganic salt with established industrial production methods and long-standing pharmaceutical use.
| IP category |
Commercial relevance |
| Composition-of-matter patents |
Negligible |
| Core manufacturing patents |
Limited and generally expired or nonexclusive |
| Formulation patents |
Possible only for specific drug products or delivery systems |
| Method-of-use patents |
Relevant to a drug formulation, not normally to the excipient itself |
| Process know-how |
Moderate importance for purity, particle size, drying, and contamination control |
| Trade secrets |
Possible at the manufacturing-site level |
| Trademark protection |
Supplier-specific, not molecule-specific |
The defensible asset is quality-system execution rather than patent exclusivity. A supplier may protect a particular production process, crystal form, particle-size profile, or low-impurity grade through know-how, but these protections rarely create durable monopoly economics.
What is the FDA regulatory status of sodium phosphate, monobasic, anhydrous?
Sodium phosphate, monobasic, anhydrous is used as an inactive ingredient in FDA-regulated drug products. The FDA Inactive Ingredient Database records inactive-ingredient use by route and dosage form, although database entries should be interpreted by route, maximum potency, and dosage-form context rather than as blanket approval for every application [2].
The regulatory framework includes:
- USP-NF monograph compliance where applicable
- FDA inactive-ingredient precedent
- Drug Master File or equivalent supplier documentation where used
- Current Good Manufacturing Practice controls
- Elemental impurity assessment under ICH Q3D
- Extractables, leachables, and container-closure review where relevant
- Regional compliance with Ph. Eur., BP, JP, or other national standards
The European Medicines Agency classifies excipients within pharmaceutical quality and regulatory documentation frameworks. Excipients must be appropriately characterized and controlled in the finished-product application [3].
Orange Book status
Sodium phosphate, monobasic, anhydrous does not have an Orange Book listing as a standalone active pharmaceutical ingredient. The Orange Book concerns approved drug products, patents, and regulatory exclusivities associated with finished medicines, not commodity excipients [4].
Paragraph IV challenges
Paragraph IV litigation generally targets patents listed for an approved drug product. A supplier of sodium phosphate monobasic would not normally face a Paragraph IV challenge over the excipient itself. Paragraph IV activity can still affect demand indirectly if a phosphate-buffered drug loses exclusivity and generic manufacturers enter the market.
When does sodium phosphate, monobasic, anhydrous lose exclusivity?
The excipient has no meaningful remaining exclusivity period. It is a mature commodity with no commercially relevant product-specific patent expiration date controlling market access.
Market access is instead constrained by:
- Customer qualification
- Pharmacopeial specifications
- Regulatory filing commitments
- Manufacturing-site approval
- Supply-chain audits
- Change-control obligations
- Existing formulation validation
A new supplier can generally enter the market without licensing an active patent. Commercial entry still requires a compliant manufacturing system, validated analytical methods, reliable impurity data, and customers willing to qualify the source.
What manufacturing and IP barriers affect supply?
Manufacturing typically involves phosphoric acid neutralization with a sodium base, followed by purification, crystallization, drying, milling, and packaging. The critical variables include:
- Phosphate purity
- Sodium-to-phosphorus stoichiometry
- Trace metals
- Fluoride and arsenic control
- Residual moisture
- Crystal phase
- Particle size
- Bulk density
- Hygroscopicity
- Microbial quality
Anhydrous production can require tighter drying and moisture control than the monohydrate. Inconsistent dehydration can create phase variability or cause the material to absorb moisture during storage.
The most important barriers are operational rather than legal. A supplier that loses control of moisture, trace metals, or particle-size distribution can create blend, dissolution, or stability problems for customers.
What are the pricing and financial drivers?
The product is exposed to commodity-cost variables, especially phosphoric acid, sodium inputs, energy, labor, packaging, freight, and quality testing. Pharmaceutical-grade material commands a premium over industrial or laboratory grades because of documentation and quality controls.
| Financial driver |
Directional effect |
| Phosphoric acid prices |
Direct input-cost pressure |
| Energy and drying costs |
Higher impact for anhydrous production |
| Freight and packaging |
Significant for low-value, high-volume shipments |
| Pharmaceutical demand |
Supports baseline volume |
| Generic-drug launches |
Increases volume but intensifies price competition |
| Sterile and biologic applications |
Supports higher-value grades |
| Dual sourcing |
Limits supplier pricing power |
| Regulatory requalification |
Raises switching costs |
| Regional capacity |
Influences lead times and delivered pricing |
| Monohydrate substitution |
Caps long-term price expansion |
Gross margins are likely higher for validated pharmaceutical grades than for industrial material, but the product remains vulnerable to competitive bidding. Suppliers can improve economics through production scale, regional inventory, integrated phosphate sourcing, and broad customer portfolios.
Standalone revenue exposure is difficult to calculate because companies do not generally report anhydrous sodium phosphate sales separately. The more useful financial metric is contribution to a broader excipient or inorganic-phosphate portfolio.
What licensing deals, litigation, and settlements affect the market?
No major public licensing structure is required to commercialize sodium phosphate, monobasic, anhydrous as a commodity excipient. Customers usually purchase under supply agreements, quality agreements, framework contracts, or distributor arrangements rather than royalty-bearing IP licenses.
Product-specific patent litigation and settlement agreements are not central market drivers. The relevant legal issues are more often:
- Product-quality disputes
- Supply interruption claims
- Specification deviations
- Change-control disagreements
- Regulatory inspection findings
- Contractual indemnity
- Contamination or recall exposure
Litigation affecting a finished phosphate-buffered drug can change demand for a particular formulation, but it does not normally alter the competitive structure of the excipient market.
What generic launch scenarios affect demand?
Generic entry can produce two opposing effects. It can increase aggregate excipient volume by adding manufacturers and finished-product units. It can also reduce the originator’s formulation volume and force lower-cost sourcing.
| Scenario |
Effect on anhydrous sodium phosphate demand |
| Originator exclusivity ends, one generic enters |
Moderate volume increase |
| Multiple generics enter |
Higher volume, lower price pressure |
| Generic uses monohydrate |
Volume loss for anhydrous grade |
| Generic retains the originator formulation |
Stronger demand continuity |
| Reformulation changes buffer system |
Potential displacement |
| Drug is discontinued |
Direct volume loss |
| Biologic or biosimilar expansion |
Incremental demand for qualified buffer grades |
The highest-value demand comes from products where the anhydrous form is specified in the approved formulation or manufacturing process. The greatest substitution risk occurs in products where the salt form can be changed without material regulatory or stability consequences.
How does geographic coverage affect the market?
Asia is central to phosphate-chemical production and pharmaceutical manufacturing. India and China provide substantial capacity, while Europe and North America remain important for regulated supply, formulation development, distribution, and customer qualification.
Regional dynamics include:
- North America: strong demand for USP-grade material and domestic or nearshore inventory
- Europe: emphasis on Ph. Eur. compliance, supplier qualification, and dual sourcing
- India: expanding generic-drug and pharmaceutical-ingredient demand
- China: large chemical capacity and competitive pricing, with customer-specific regulatory considerations
- Latin America: distributor-led access and import dependence
- Middle East and Africa: reliance on regional distributors and imported pharmaceutical grades
Freight disruption, export controls, port congestion, and changes in chemical-production economics can affect delivered cost even when global manufacturing capacity is adequate.
What is the financial trajectory for sodium phosphate, monobasic, anhydrous?
The likely financial trajectory is steady nominal growth with limited structural pricing power. Revenue can rise through pharmaceutical-volume expansion, inflation pass-through, biologic manufacturing, and higher demand for documented grades. Margin expansion is less likely unless a supplier has integrated raw-material sourcing or a differentiated high-purity product.
Base-case outlook
The base case is low-to-mid single-digit volume growth across pharmaceutical applications, with pricing broadly tracking input costs and inflation. Mature oral solid dosage demand should remain stable. Higher-specification applications may grow faster but represent a smaller portion of total volume.
Upside factors
- Greater generic manufacturing activity
- Expanded biologic and biosimilar production
- Increased use of validated dual suppliers
- Regional inventory requirements
- Demand for low-metal and low-endotoxin grades
- Pharmaceutical manufacturing relocation into India and Southeast Asia
Downside factors
- Substitution by sodium phosphate monobasic monohydrate
- Replacement by citrate, acetate, histidine, or other buffers
- Customer consolidation and annual price negotiations
- Industrial oversupply
- Energy and freight inflation
- Drug discontinuations
- Formulation simplification
Key Takeaways
- Sodium phosphate, monobasic, anhydrous is a mature pharmaceutical excipient with stable baseline demand.
- Its main functions are buffering, pH adjustment, and tonicity control.
- The closest substitute is sodium phosphate, monobasic, monohydrate.
- The product has no meaningful standalone patent exclusivity or Orange Book protection.
- Regulatory and quality qualification create stronger barriers than intellectual property.
- Pricing power is limited because multiple suppliers and substitute phosphate forms exist.
- Financial performance depends on pharmaceutical volume, raw-material costs, quality-grade premiums, freight, and supplier qualification.
- Generic and biosimilar growth can increase demand, but the effect depends on whether manufacturers retain the anhydrous form.
- The strongest commercial position belongs to suppliers with pharmacopeial compliance, low-impurity control, validated manufacturing, regional inventory, and dual-source credibility.
FAQs
Is sodium phosphate, monobasic, anhydrous the same as sodium phosphate monobasic monohydrate?
No. The anhydrous form contains no stoichiometric water of crystallization, while the monohydrate contains one water molecule per molecule of sodium phosphate. They require different formulation calculations.
Is sodium phosphate monobasic anhydrous used in injectable drugs?
It can be used in selected parenteral formulations and process solutions, subject to applicable quality, sterility, endotoxin, elemental-impurity, and regulatory requirements.
Does sodium phosphate monobasic anhydrous have a Drug Master File?
Some suppliers may maintain confidential regulatory files or customer-specific documentation, but a Drug Master File is supplier-specific and is not an inherent property of the chemical.
Can pharmaceutical manufacturers change suppliers without regulatory approval?
A supplier change may require internal qualification, comparability testing, stability work, quality-agreement updates, and regulatory notification or filing, depending on the product, jurisdiction, and change classification.
Which replacement buffers compete with sodium phosphate monobasic anhydrous?
Potential alternatives include sodium citrate, acetate buffers, histidine, tromethamine, and other phosphate salts. Suitability depends on target pH, ionic strength, stability, compatibility, route of administration, and the approved formulation.
References
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National Center for Biotechnology Information. (2024). PubChem compound summary for CID 23672064, sodium phosphate, monobasic. PubChem. https://pubchem.ncbi.nlm.nih.gov/compound/Sodium-phosphate-monobasic
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U.S. Food and Drug Administration. (2024). Inactive Ingredient Database. https://www.accessdata.fda.gov/scripts/cder/iig/index.cfm
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European Medicines Agency. (2016). Guideline on excipients in the dossier for application for marketing authorisation of a medicinal product. https://www.ema.europa.eu/
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U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
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United States Pharmacopeial Convention. (2024). United States Pharmacopeia and National Formulary. USP Convention.
