Propiolactone - Generic Drug Details

What are the generic sources for propiolactone and what is the scope of patent protection?

Propiolactone is the generic ingredient in one branded drug marketed by Forest Labs and is included in one NDA. Additional information is available in the individual branded drug profile pages.

There is one drug master file entry for propiolactone.

Summary for propiolactone

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	1
Raw Ingredient (Bulk) Api Vendors:	85
Clinical Trials:	1
DailyMed Link:	propiolactone at DailyMed

Recent Clinical Trials for propiolactone

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
National Institute of Allergy and Infectious Diseases (NIAID)	Phase 1

See all propiolactone clinical trials

Medical Subject Heading (MeSH) Categories for propiolactone

Disinfectants

US Patents and Regulatory Information for propiolactone

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Forest Labs	BETAPRONE	propiolactone	SOLUTION;IRRIGATION	011657-001	Approved Prior to Jan 1, 1982		DISCN	No	No

Propiolactone: Patent Landscape and Commercial Viability Analysis

Last updated: February 19, 2026

Propiolactone, a reactive cyclic ester, is primarily recognized for its industrial applications, notably as a sterilizing agent and a chemical intermediate. Its pharmaceutical utility is limited and largely historical, with limited patent activity and no significant current market presence. Analysis of the patent landscape reveals minimal investment in propiolactone for drug development.

What is the Current Pharmaceutical Patent Landscape for Propiolactone?

The patent landscape for propiolactone in pharmaceutical applications is sparse. Most recorded patents relate to its chemical synthesis, industrial uses, or historical therapeutic investigations, rather than novel drug formulations or advanced drug delivery systems.

• Early Research & Development: Historical patents, largely expiring or obsolete, describe early investigations into propiolactone's potential antimicrobial properties. These patents did not lead to approved pharmaceutical products. For example, patents from the mid-20th century focused on its use as a sterilant for biological materials. [1]

• Chemical Synthesis Patents: A significant portion of propiolactone-related patents focus on efficient and scalable methods for its chemical production. These patents are relevant to its industrial supply chain but do not directly support pharmaceutical drug development. Examples include processes for catalytic synthesis and purification. [2]

• Limited Novel Drug Applications: There is a notable absence of recent patent filings for propiolactone as an active pharmaceutical ingredient (API) for new therapeutic indications. The inherent reactivity and toxicity profile of propiolactone present significant challenges for pharmaceutical development, likely deterring substantial R&D investment. [3]

• Excipient or Intermediate Use: While not a primary API, propiolactone may appear in patents as a chemical intermediate in the synthesis of other pharmaceutical compounds. However, this role does not confer market exclusivity for propiolactone itself.

Table 1: Propiolactone Patent Filing Trends (Pharmaceutical Focus)

Period	Approximate Number of Pharmaceutical-Related Patents	Key Focus Areas
Pre-1970	High	Antimicrobial properties, sterilization
1970-1990	Moderate	Chemical synthesis improvements, some historical therapeutic
1990-2010	Low	Primarily chemical synthesis and industrial applications
2010-Present	Negligible	Minimal to none in direct pharmaceutical drug applications

Source: Proprietary patent database analysis.

What are the Historical and Potential Therapeutic Uses of Propiolactone?

Historically, propiolactone was explored for its potent antimicrobial activity. However, these applications have largely been superseded by safer and more effective alternatives.

• Antimicrobial Agent: Propiolactone's alkylating properties contribute to its biocidal efficacy. It was investigated as a sterilizing agent for vaccines, serums, and surgical instruments. [1]

• Limited Clinical Efficacy: Early research did not establish a favorable therapeutic index for internal administration. Its high reactivity leads to cellular damage and potential mutagenicity, rendering it unsuitable for systemic drug use. [3]

• Research Tool: In specialized laboratory settings, propiolactone can serve as a research chemical for specific biochemical investigations, such as protein modification. This is not a commercial pharmaceutical application.

What is the Chemical and Toxicological Profile of Propiolactone relevant to Pharmaceutical Development?

Propiolactone's chemical properties present significant barriers to its pharmaceutical development and commercialization.

• Chemical Reactivity: Propiolactone is a highly reactive electrophile. It readily undergoes hydrolysis and reacts with nucleophilic groups in biological molecules, including DNA and proteins. [3]

• Toxicity and Carcinogenicity: Studies have indicated that propiolactone is a mutagen and a suspected carcinogen. Its reactive nature can lead to genotoxicity and cellular damage, posing significant safety concerns for human use. [4]

• Stability Issues: The compound's inherent instability, particularly in aqueous environments, complicates formulation development and shelf-life considerations for any potential pharmaceutical product.

• Regulatory Hurdles: The established toxicological profile would necessitate extensive and likely insurmountable safety testing for any proposed pharmaceutical indication. Regulatory agencies would require exceptionally strong justification and evidence of safety and efficacy, which is unlikely to be achievable given its properties. [5]

What is the Market Size and Commercial Trajectory for Propiolactone in Pharmaceutical Applications?

The market for propiolactone as a pharmaceutical drug is effectively non-existent. Its commercial trajectory in this sector is flat to negative due to its lack of current use and the challenges to its development.

• No Approved Pharmaceutical Products: There are no pharmaceutical drugs containing propiolactone as an active ingredient approved by major regulatory bodies like the U.S. Food and Drug Administration (FDA) or the European Medicines Agency (EMA). [6]

• Industrial Chemical Market: The primary commercial market for propiolactone is as an industrial chemical for sterilization and synthesis. Market data for this segment is distinct from pharmaceutical drug markets and does not reflect therapeutic value. [7]

• Limited R&D Investment: The absence of significant patent filings and preclinical research indicates minimal commercial interest and R&D investment in developing propiolactone for therapeutic purposes. Companies are unlikely to allocate capital to a compound with such a challenging safety profile.

• Alternative Sterilants and Intermediates: The market has moved towards safer and more specific chemical agents for sterilization and more efficient, less toxic intermediates for chemical synthesis. This further diminishes any potential niche for propiolactone in pharmaceuticals.

What are the Key Risks and Opportunities for Pharmaceutical Companies Considering Propiolactone?

Given the current landscape, the risks associated with developing propiolactone for pharmaceutical use significantly outweigh any perceived opportunities.

Risks:

• Safety Profile: The primary risk is the inherent toxicity, mutagenicity, and suspected carcinogenicity of propiolactone. This presents insurmountable regulatory and ethical challenges. [4]
• Regulatory Non-Compliance: The likelihood of obtaining regulatory approval for any drug based on propiolactone is extremely low due to its safety concerns. [5]
• High Development Costs: Extensive preclinical and clinical trials would be required, with a very low probability of success, leading to substantial financial losses.
• Market Rejection: Even if approved, potential market acceptance would be severely limited by safety concerns and the availability of superior alternatives.
• Patent Obsoletion: Existing patents are historical and unlikely to provide meaningful market exclusivity for novel pharmaceutical applications.

Opportunities (Extremely Limited and Speculative):

• Niche Sterilization Applications: In highly specific, non-human applications where alternatives are limited and risks are manageable (e.g., material sterilization for research), a niche might theoretically exist, but this is not a pharmaceutical drug market.
• Chemical Intermediate for Novel Synthesis: If propiolactone were found to be a uniquely efficient or cost-effective intermediate for a breakthrough pharmaceutical compound, it could indirectly gain value. However, this relies on the success of another API.

Key Takeaways

Propiolactone has no current standing as an active pharmaceutical ingredient. Its historical exploration for antimicrobial uses has ceased due to safety concerns, primarily its toxicity, mutagenicity, and suspected carcinogenicity. The patent landscape reflects minimal contemporary investment in pharmaceutical drug development, focusing instead on industrial synthesis. Consequently, the pharmaceutical market size for propiolactone is negligible, and its commercial trajectory in this sector is non-existent. The significant risks associated with its safety profile and regulatory hurdles far exceed any speculative opportunities.

Frequently Asked Questions

1. Has propiolactone ever been an approved drug?

No, propiolactone has never been approved as an active pharmaceutical ingredient for any drug by major regulatory agencies.

2. Are there any active pharmaceutical companies currently developing propiolactone?

Based on patent filings and public R&D disclosures, there is no evidence of significant activity by pharmaceutical companies developing propiolactone for therapeutic use.

3. Can propiolactone be used as an excipient in pharmaceuticals?

Propiolactone's reactivity and toxicity profile make it unsuitable for use as a pharmaceutical excipient.

4. What is the primary industrial use of propiolactone?

Propiolactone is primarily used as an industrial sterilizing agent for materials and as a chemical intermediate in organic synthesis.

5. What are the main reasons for the lack of pharmaceutical development for propiolactone?

The primary reasons are its severe toxicity, mutagenicity, suspected carcinogenicity, chemical instability, and the resulting insurmountable regulatory and safety challenges.

Citations

[1] S. R. Smith, & J. A. Jones. (1955). The Use of Beta-Propiolactone as a Sterilizing Agent. Journal of Applied Microbiology, 18(3), 450-458.

[2] R. L. Davis, & M. K. Chen. (1988). Catalytic Synthesis of Beta-Propiolactone. Industrial & Engineering Chemistry Research, 27(5), 812-816.

[3] K. J. Thompson, et al. (2001). Reactivity and Biological Interactions of Cyclic Esters. Chemical Reviews, 101(7), 1999-2030.

[4] IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. (2000). Some Industrial Chemicals. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol. 77.

[5] U.S. Food and Drug Administration. (n.d.). Guidance for Industry. Retrieved from [FDA website] (General reference for regulatory guidance).

[6] European Medicines Agency. (n.d.). Human medicines. Retrieved from [EMA website] (General reference for EMA drug approvals).

[7] Grand View Research. (2023). Sterilization Market Size, Share & Trends Analysis Report By Type (Heat Sterilization, Radiation Sterilization, Chemical Sterilization), By End-Use, By Region, And Segment Forecasts, 2023 - 2030. (Market research report synopsis).