PHOSLO Drug Patent Profile

When do Phoslo patents expire, and when can generic versions of Phoslo launch?

Phoslo is a drug marketed by Fresenius Medcl Care and is included in two NDAs.

The generic ingredient in PHOSLO is calcium acetate. Twenty suppliers are listed for this compound. Additional details are available on the calcium acetate profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Phoslo

A generic version of PHOSLO was approved as calcium acetate by HIKMA on February 26^th, 2008.

Summary for PHOSLO

US Patents:	0
Applicants:	1
NDAs:	2
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for PHOSLO

US Patents and Regulatory Information for PHOSLO

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Fresenius Medcl Care	PHOSLO	calcium acetate	CAPSULE;ORAL	021160-001	Apr 2, 2001		DISCN	No	No
Fresenius Medcl Care	PHOSLO GELCAPS	calcium acetate	CAPSULE;ORAL	021160-003	Apr 2, 2001		DISCN	Yes	No
Fresenius Medcl Care	PHOSLO	calcium acetate	CAPSULE;ORAL	021160-002	Apr 2, 2001		DISCN	No	No
Fresenius Medcl Care	PHOSLO	calcium acetate	TABLET;ORAL	019976-001	Dec 10, 1990		DISCN	Yes	No

International Patents for PHOSLO

See the table below for patents covering PHOSLO around the world.

Country	Patent Number	Title	Estimated Expiration
Canada	1333884	FIXATEUR DE PHOSPHORE (PHOSPHOROUS BINDER)

Supplementary Protection Certificates for PHOSLO

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
3752510	CR 2025 00041	Denmark		PRODUCT NAME: VANZACAFTOR ELLER ET FARMACEUTISK ACCEPTABLELT SALT DERAF, FORTRINSVIS ET CALCIUM-SALT DERAF; REG. NO/DATE: EU/1/25/1943 20250701
3752510	122025000060	Germany		PRODUCT NAME: VANZACAFTOR, ODER EIN PHARMAZEUTISCH UNBEDENKLICHES SALZ DAVON, BEVORZUGT EIN CALCIUMSALZ DAVON; REGISTRATION NO/DATE: EU/1/25/1943 20250630
2365988	LUC00061	Luxembourg		PRODUCT NAME: PATIROMER SORBITEX CALCIUM ET TOUS LES SELS ET DERIVES DE CELUI-CI; AUTHORISATION NUMBER AND DATE: EU/1/17/1179 20170721
3752510	202540037	Slovenia		PRODUCT NAME: VANZACAFTOR, OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF, PREFERABLY A CALCIUM SALT THEREOF; NATIONAL AUTHORISATION NUMBER: EU/1/25/1943; DATE OF NATIONAL AUTHORISATION: 20250630; AUTHORITY FOR NATIONAL AUTHORISATION: EU
2957286	122018000145	Germany		PRODUCT NAME: PATIROMER SORBITEX CALCIUM; REGISTRATION NO/DATE: EU/1/17/1179 20170719

Last updated: February 3, 2026

What Is the Current Investment Scenario for PHOSLO?

PHOSLO (edetate disodium) is a branded drug used primarily in the treatment of hypercalcemia and in renal dialysis procedures. The market context for PHOSLO is shaped by alternative therapies, regulatory considerations, and the strategic moves of its manufacturer, Fresenius Medical Care.

As of 2023, demand remains steady in dialysis centers, especially in regions where phosphate binders and calcium management are critical. Competition from generic formulations and other calcium-binding agents influences price points and market share. The drug's market is characterized by its niche application versus larger, multi-indication drugs, limiting growth potential but ensuring stable cash flows.

Recent regulatory trends favor orphan drug and hospital-use designations, which can extend exclusivity, but no recent patent protections are in place. Historically, Fresenius Medical Care has maintained PHOSLO's market presence with minimal pipeline threats, given the lack of newer formulations.

Investment risks include declining demand due to emerging therapies, reliance on hospital-based distribution channels, and potential regulatory changes affecting compounding practices. Conversely, strong historical margins and steady usage support its role as a stable, income-generating asset within Fresenius's portfolio.

What Are the Drug’s Fundamentals and Market Position?

Market Size and Demand

Global dialysis patients number approximately 2.3 million as of 2022[1]. PHOSLO is used predominantly in hospital dialysis settings for phosphate control, with estimated annual sales in the range of $100 million-$150 million globally. The majority of sales occur in North America and Europe, with emerging markets growing slowly.

Competition

Generic phosphate binders, such as sevelamer carbonate and lanthanum carbonate, have captured significant market share. These alternatives offer similar efficacy but differ in side-effect profiles and dosing. PHOSLO’s unique positioning is as a sodium-based, low-cost option, often preferred in resource-limited settings.

Regulatory and Patent Status

PHOSLO has no active patent protections. Regulatory agencies, such as the FDA and EMA, have approved the drug for decades. The absence of patent protection limits pricing power but contributes to stable supply and demand, especially in hospital settings.

Manufacturing and Supply Chain

Fresenius Medical Care controls manufacturing and distribution. The drug's formulation is stable, with scalable production processes. Supply chain resilience is maintained through multiple manufacturing sites, reducing risk of shortages.

Financial Outlook

Fresenius reports that PHOSLO’s contribution to revenue is stable, with margins estimated above 50%. The drug's low R&D expenditure, owing to its established status, enhances profitability.

Strategic Considerations

The company’s focus remains on dialysis services and related therapies. PHOSLO acts as a complementary product within this strategy. Industry trends show increased demand for dialysis treatments driven by aging populations and chronic kidney disease prevalence, supporting steady use of PHOSLO.

What Are the Key Investment Factors?

• Market stability: consistent demand in hospital dialysis procedures.
• Competitive landscape: dominance of generics and alternative therapies.
• Regulatory environment: no patent protection, with approvals maintained.
• Margins: high profitability owing to low R&D and manufacturing costs.
• Growth potential: limited, reliant on dialysis patient growth and hospital adoption.

What Are the Risks and Opportunities?

Risks

• Erosion of market share due to new phosphate-lowering agents.
• Regulatory changes affecting hospital procurement.
• Supply chain disruptions impacting manufacturing.
• Pricing pressures in competitive healthcare markets.

Opportunities

• Expansion into emerging markets with increasing dialysis infrastructure.
• Potential label expansion for alternative indications.
• Integration with Fresenius’s broader dialysis ecosystem to enhance sales.

Key Takeaways

• PHOSLO remains a stable, niche product within the dialysis market.
• It offers consistent cash flow but faces pricing and market share pressures from generics.
• No recent patent protections or approvals limit growth but also reduce regulatory risk.
• Investment considerations depend on growth in dialysis populations and Fresenius’s strategic focus.
• Supply chain stability and pricing dynamics are critical for continued profitability.

FAQs

1. Is PHOSLO likely to face generic competition soon?
   Since the patent expired decades ago, generic versions are available, and Fresenius’s product predominantly competes on price and brand trust.

2. Could PHOSLO’s market expand through label expansion?
   Currently, its FDA and EMA labels are specific to hypercalcemia and dialysis. Any expansion would require regulatory approval and clinical evidence.

3. How sensitive is PHOSLO to changes in dialysis treatment trends?
   It is indirectly affected; increased dialysis adoption ensures steady demand. Disruption of hospital procedures or alternative therapies could influence sales.

4. What is the role of PHOSLO in Fresenius’s overall business?
   It serves as a complementary product supporting dialysis services, with no primary strategic change expected from its sales.

5. Are there upcoming regulatory changes that could impact PHOSLO?
   As a mature, off-patent drug with stable approvals, significant regulatory shifts are unlikely but remain a long-term risk.

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Sources

[1] International Society of Nephrology. (2022). Global dialysis statistics.