SILDAFLO Drug Patent Profile

Which patents cover Sildaflo, and when can generic versions of Sildaflo launch?

Sildaflo is a drug marketed by Franklin Pharms and is included in one NDA.

The generic ingredient in SILDAFLO is silver sulfadiazine. There are twenty-two drug master file entries for this compound. Fourteen suppliers are listed for this compound. Additional details are available on the silver sulfadiazine profile page.

Summary for SILDAFLO

US Patents:	0
Applicants:	1
NDAs:	1

US Patents and Regulatory Information for SILDAFLO

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Franklin Pharms	SILDAFLO	silver sulfadiazine	DRESSING;TOPICAL	019608-001	Nov 30, 1989		DISCN	No	No

International Patents for SILDAFLO

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

Country	Patent Number	Title	Estimated Expiration
Japan	H0566147
South Africa	8407592
Israel	73188	SYNTHETIC RESIN WOUND DRESSING
Australia	563517

Supplementary Protection Certificates for SILDAFLO

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
0350733	SPC/GB03/034	United Kingdom		PRODUCT NAME: MOXIFLOXACIN AND PHARMACEUTICALLY USABLE HYDRATES AND ACID ADDITION SALTS THEREOF AND THE ALKALI METAL, ALKALINE EARTH METAL, SILVER AND GUANIDINIUM SALTS OF THE UNDERLYING CARBOXYLIC ACIDS AND THE RACEMATES THEREOF; REGISTERED: DE 45263.00.00 19990621; UK PL 000 10/0291 20030313

Summary

Last updated: February 15, 2026

SILDAFLO (generic name: sildenafil) is a PDE5 inhibitor used primarily for erectile dysfunction (ED), pulmonary arterial hypertension (PAH), and other indications. Its market dynamics are driven by patent expiration, regulatory approvals for new indications, and the competitive landscape. Investment considerations include patent expiry timeline, pipeline developments, manufacturing capacity, and competitive pressures from generics and alternative therapies.

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What Is the Current Patent Situation and Market Exclusivity?

Sildenafil's primary patent protection in the U.S. expired in December 2020. Multiple generic formulations entered the market shortly afterward, leading to a significant price erosion. Patent protection in other key markets like the EU extended until 2021-2022 in some cases, but generic availability is now widespread globally.

Region	Patent Expiry	Status of Generics	Impact on Pricing
US	December 2020	Multiple generics available	Price decline estimated at 80% since 2020
EU	2021-2022	Generics available	Significant price erosion
Japan	2021	Some generics available	Price reduction underway

The patent landscape shifts investment risk to reliance on brand differentiation or novel indications rather than simple branded sales.

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What Are the Leading Indications and Market Sizes?

Erectile Dysfunction (ED)

• Global market size (2022): USD 4.3 billion.
• CAGR (2022-2028): 4.2%.
• Key players: Pfizer's original Viagra (sildenafil), now largely commoditized.

Pulmonary Arterial Hypertension (PAH)

• Market size (2022): USD 5 billion.
• Growth driven by expanding indications and approval for new patient pediatric populations.
• Sildenafil is marketed as Revatio for PAH in multiple markets.

Other Potential Uses

• Altitude sickness, Raynaud’s phenomenon (investigational).
• Accelerating approval for new indications could boost revenues.

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What Are the Key Drivers and Risks for Investment?

Drivers:

• Pipeline extensions for new indications.
• Market share retention within PAH segment.
• Potential for biosimilar entry to pressure prices.
• Growing prescription rates in emerging markets.

Risks:

• Entry of generics eroding revenue.
• Decline in prescribing due to newer ED treatments (e.g., Tadalafil, Vardenafil).
• Regulatory hurdles in off-label uses.
• Manufacturing supply chain disruptions.

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What Are the Competitive Dynamics?

Generic sildenafil dominates the ED market due to patent expiry, reducing prices sharply. The branded product maintains importance in PAH, especially in markets where Revatio formulations are protected or preferred.

Emerging therapies like Tadalafil (Cialis) and Vardenafil (Levitra) challenge sildenafil's market share, especially given longer half-lives and dosing flexibility. Biosimilars and generics have captured most of the ED revenue base, limiting upside for brand holders.

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How Do Pipeline and Regulatory Developments Affect Future Outlook?

• New indications: Trials for pediatric PAH and altitudinal uses could open new revenue streams.
• Formulation innovations: Sustained-release formulations or combination drugs may command premium prices.
• Regulatory delays: New filings or approvals in major markets can influence sales trajectories, but delays or refusals pose risks.

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What Are the Manufacturing and Supply Chain Considerations?

Sildenafil is produced through established chemical synthesis processes. Manufacturers with licensed production facilities (e.g., Pfizer, generic companies) dominate the supply chain. Capacity constraints are unlikely; however, quality and regulatory compliance remain critical for market access, especially post-patent expiry.

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What Are Investment Recommendations?

Category	Outlook	Rationale
Established brands	Declining but steady in PAH	Revenue stabilization from limited indications
Pipeline developments	Moderate growth potential	New indications and formulations can create upside
Generic competition	High market share erosion	Price erosions set to continue in ED segment
Emerging markets	Growth in prescription volume	Rapid uptake among growing health systems

Investors should focus on companies with diversified pipelines, strong manufacturing capabilities, and strategic approaches to biosimilar competition.

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Key Takeaways

• Patent expiration largely eliminated brand exclusivity for sildenafil.
• Generics dominate the ED market, significantly compressing prices.
• The PAH segment remains critical for branded revenues, with potential growth from new indications.
• Pipeline projects for new formulations and uses could provide upside.
• Competitive landscape shifting towards biosimilars and alternative therapies.

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FAQs

1. What are the main factors influencing sildenafil's market share? Patent expiration, introduction of generics, competition from alternative ED drugs, and regulatory approvals for new indications.

2. How does the pipeline affect sildenafil's long-term value? Pipeline prospects for new indications or formulations may support revenue in niche segments or extend product lifecycle.

3. Are biosimilars a threat? While biosimilars target the PAH market, their impact on sildenafil remains limited as it is a small molecule. Biosimilars mainly threaten biologics.

4. What strategic moves can companies make to maintain profitability? Focus on pipeline expansion, entering emerging markets, innovating formulations, and strategic partnerships for distribution.

5. What is the outlook for branded sildenafil sales in the next five years? Declining in ED due to generic competition but sustained in niche markets like PAH; overall revenue expected to decrease sharply in the ED segment.

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References

[1] Market Research Future. "Sildenafil Market Forecast." 2022. [2] IBISWorld. "Erectile Dysfunction Drugs Industry Report." 2022. [3] U.S. Patent and Trademark Office. "Patent expiry data for sildenafil." 2020. [4] EvaluatePharma. "PAH Market Dynamics." 2022. [5] FDA. "Revatio (sildenafil) approval and indications." 2022.