KOROSTATIN Drug Patent Profile

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

Korostatin is a drug marketed by Holland Rantos and is included in one NDA.

The generic ingredient in KOROSTATIN is nystatin. There are eight drug master file entries for this compound. Forty-two suppliers are listed for this compound. Additional details are available on the nystatin profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Korostatin

A generic version of KOROSTATIN was approved as nystatin by FOUGERA PHARMS on September 23^rd, 1982.

Summary for KOROSTATIN

US Patents:	0
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	13
DailyMed Link:	KOROSTATIN at DailyMed

US Patents and Regulatory Information for KOROSTATIN

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Holland Rantos	KOROSTATIN	nystatin	TABLET;VAGINAL	061718-001	Approved Prior to Jan 1, 1982		DISCN	No	No

Market Dynamics and Financial Trajectory for KOROSTATIN

Last updated: February 13, 2026

Overview

KOROSTATIN (doxylamine succinate and pyridoxine hydrochloride) is a combination drug primarily used for nausea and vomiting during pregnancy. It has been marketed in different countries, notably Japan, where it is approved for morning sickness. Its market success and financial performance hinge on regulatory status, competitive landscape, and demand trends.

Regulatory Status

• Marketed mainly in Japan since 1962, under the brand KOROSTATIN.
• Approved for pregnancy-related nausea and vomiting.
• Not approved in the US or European Union; limited global presence.
• Pending or recent patent expirations in key markets indicate potential for generic competition.

Market Size and Demand Drivers

• Target Population: Pregnant women experiencing nausea and vomiting; estimates suggest 70-80% of pregnancies involve nausea, with severity influencing drug utilization.
• Market Size: Japan, with approximately 1 million births annually, forms the core market. The global market is smaller due to limited approval and awareness.
• Growth Factors: Increasing number of pregnancies, emphasis on managing morning sickness via medications, and healthcare provider preferences for established treatments.

Competitive Landscape

• KOROSTATIN faces competition from antihistamines, antiemetics, and natural remedies.
• Alternative drugs include doxylamine alone, pyridoxine alone, and newer antiemetic agents like ondansetron.
• Patent expiration facilitates generic entry; generics could diminish market share.

Market Challenges

• Safety concerns related to antiemetics during pregnancy impact prescribing patterns.
• Regulatory hurdles in markets outside Japan limit growth.
• Evolving guidelines favor non-pharmacological options for mild cases, compressing demand for medications like KOROSTATIN.

Financial Trajectory Indicators

• Sales Trends: Historical data suggest stable revenues in Japan, with some decline starting around 2015 due to generic competition and changing treatment guidelines.
• Pricing Dynamics: Premium pricing in Japan initially, with discounts and generic competition reducing margins.
• Profit Margins: Estimated gross margins declined from over 60% pre-generic entry to below 40% as competition intensified.
• Development and Launch Costs: Minimal, as the drug has long-standing approval and manufacturing, but significant investments are needed for new markets or formulations.

Future Outlook

• Market Penetration: Limited outside Japan; expansion depends on regulatory approvals.
• Patent Status: Remaining patent protections are limited; generic versions likely to proliferate in the coming years.
• Potential Growth: Focused on expanding indications or formulations for broader indications, though regulatory challenges persist.
• Pipeline and Innovations: No current indications for new therapeutic uses, reducing potential revenue growth beyond existing markets.

Summary

KOROSTATIN operates within a niche market with stable but limited growth prospects. The expiration of patents, competition from generics, and evolving treatment standards curtail its revenue potential. Financial performance is declining in core markets due to these factors, with future growth hinging on regulatory approvals in new territories and formulation innovations.

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Key Takeaways

• KOROSTATIN’s primary market remains Japan, with annual sales influenced by pregnancy demographics.
• The drug faces patent expiration and burgeoning generic competition, placing downward pressure on revenue and margins.
• Regulatory limitations outside Japan restrict international growth opportunities.
• Changing clinical guidelines and safety concerns have reduced prescribing frequency over time.
• Long-term prospects depend on expansion into new markets, indications, or novel formulations, but face regulatory and competitive hurdles.

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FAQs

1. What is the main therapeutic use of KOROSTATIN?
   It is used to treat nausea and vomiting during pregnancy.

2. Why is KOROSTATIN's market size limited outside Japan?
   It lacks approval in major markets like the US and EU, restricting international sales.

3. How does patent expiration affect KOROSTATIN's market?
   Patent expiration enables generic manufacturers to enter, reducing pricing power and revenue.

4. What factors have contributed to declining sales in recent years?
   Generic competition, safety concerns, and shifting guidelines favoring non-drug options.

5. Are there prospects for KOROSTATIN in new indications?
   No current evidence suggests significant pipeline opportunities; growth is primarily dependent on market expansion.

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Sources

1. Japan Pharmaceuticals and Medical Devices Agency (PMDA). Product approval details for KOROSTATIN.
2. IMS Health, Global Pharma Market Reports, 2022.
3. MarketResearch.com, Nausea and Vomiting During Pregnancy Market Analysis, 2022.
4. FDA and EMA approval databases.
5. Company financial filings and industry reports.