LOTRONEX Drug Patent Profile

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

Lotronex is a drug marketed by Legacy Pharma and is included in one NDA.

The generic ingredient in LOTRONEX is alosetron hydrochloride. There are three drug master file entries for this compound. Eight suppliers are listed for this compound. Additional details are available on the alosetron hydrochloride profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Lotronex

A generic version of LOTRONEX was approved as alosetron hydrochloride by AMNEAL PHARMS on December 22^nd, 2016.

Summary for LOTRONEX

US Patents:	0
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	2
Raw Ingredient (Bulk) Api Vendors:	158
Drug Prices:	Drug price information for LOTRONEX
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for LOTRONEX
What excipients (inactive ingredients) are in LOTRONEX?	LOTRONEX excipients list
DailyMed Link:	LOTRONEX at DailyMed

See drug prices for LOTRONEX

Pharmacology for LOTRONEX

Drug Class	Serotonin-3 Receptor Antagonist
Mechanism of Action	Serotonin 3 Receptor Antagonists

Paragraph IV (Patent) Challenges for LOTRONEX

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
LOTRONEX	Tablets	alosetron hydrochloride	0.5 mg and 1 mg	021107	1	2010-12-02

US Patents and Regulatory Information for LOTRONEX

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-002	Dec 23, 2003	AB	RX	Yes	No
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-001	Feb 9, 2000	AB	RX	Yes	Yes

Expired US Patents for LOTRONEX

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-002	Dec 23, 2003
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-001	Feb 9, 2000
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-001	Feb 9, 2000
Legacy Pharma	LOTRONEX	alosetron hydrochloride	TABLET;ORAL	021107-002	Dec 23, 2003

International Patents for LOTRONEX

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

Country	Patent Number	Title	Estimated Expiration
Spain	2060655
El Salvador	1998000122	MEDICAMENTOS REF. PU 3375/SV
Israel	87658	Tetrahydro-2- (1h-imidazolylmethyl) pyrido- (and azepino)[4,3-(b)] indol-1-ones, their preparation and pharmaceutical compositions containing them
Honduras	1998000155	MEDICAMENTOS
United Kingdom	8820736
New Zealand	503698	5-Hydroxytryptamine (5-HT) receptor antagonists for use in the treatment of inflammatory bowel syndrome (IBS)

Market Dynamics and Financial Trajectory for Lotronex

Last updated: July 29, 2025

Introduction

Lotronex (alosetron hydrochloride) is a prescription medication primarily marketed for women with severe diarrhea-predominant irritable bowel syndrome (IBS-D). Developed by GlaxoSmithKline (GSK) and later managed by Prometheus Laboratories (a subsidiary of Horizon Therapeutics), Lotronex has experienced a complex market journey characterized by regulatory challenges, safety concerns, and evolving demand within the niche specialty pharmaceutical segment. This article provides a comprehensive analysis of Lotronex’s market dynamics and its financial trajectory, highlighting factors influencing its performance and investment outlook.

Regulatory History and Impact on Market Dynamics

Initially approved by the U.S. Food and Drug Administration (FDA) in 2000 for female IBS-D patients, Lotronex faced immediate safety concerns. Post-marketing reports linked its use to severe ischemic colitis and bowel obstruction, leading the FDA to suspend the drug in November 2000. After a risk management program, the FDA reapproved Lotronex in 2002 with strict prescribing restrictions, including a Risk Evaluation and Mitigation Strategy (REMS).

The regulatory trajectory significantly shaped market growth. The safety concerns curtailed broad use, confining Lotronex to a specific patient subset under monitoring. According to regulatory filings, the safety profile remains a critical determinant for prescriber and patient acceptance, directly impacting revenue generation.

Market Demand and Patient Segmentation

Lotronex targets a niche market: women suffering from severe IBS-D refractory to conventional therapies. The prevalence of IBS-D in the U.S. affects roughly 10-15% of the population, translating to approximately 20 million individuals, with an estimated 15-20% experiencing severe symptoms [1]. However, due to safety concerns, the drug is prescribed to a small fraction—estimated at fewer than 1% of eligible patients—limiting its market size.

The demand dynamics are sensitive to several factors:

• Physician and Patient Perception: Safety concerns have led to conservative prescribing patterns. Education on risk management is essential to sustain and potentially expand usage.

• Alternative Therapies: The emergence of newer, gut-specific pharmacological agents, such as linaclotide and rifaximin, introduces competition, especially as safety profiles improve.

• Regulatory and Guideline Updates: Changes in clinical guidelines, emphasizing safety and alternative treatment algorithms, influence the uptake of Lotronex. Any relaxation or reinforcement of prescribing restrictions directly impacts its financial trajectory.

Competitive Landscape

The IBS-D market comprises several major players. While Lotronex was among the first targeted therapies, competitors like:

• Eluxadoline (Viberzi): Approved in 2015, with a different safety profile but similar indications, capturing a significant share due to broader safety acceptance.
• Rifaximin (Xifaxan): An antibiotic approved for IBS-D, favored for its safety and efficacy.
• Linzess (linaclotide): Primarily for IBS-C but also used off-label in some IBS-D cases.

The presence of these alternatives constrains Lotronex’s growth potential unless new safety or efficacy data enable expanded use.

Financial Trajectory and Revenue Performance

Historically, Lotronex’s revenue demonstrated a sharp decline after initial approval due to safety concerns and limited prescribing. Post-2002 reintroduction, sales remained modest, driven by the strict prescribing criteria and limited awareness.

Recent Trends:

• Market Resumption Post-2002: Annual sales hovered around $50–$100 million, with fluctuations reflecting shifts in prescriber confidence and regulatory advisories [2].
• Impact of New Indications or Extended Labeling: To bolster revenue, companies have explored expanding indications or revising safety labels. However, substantial market expansion remains constrained.
• Pricing Strategies: The drug commands premium pricing ($400–$600 per month), but payor restrictions and formulary barriers restrict access, impacting overall revenue.

Current Financial Status:

As of 2023, Lotronex remains a niche product, representing less than 1% of Horizon Therapeutics’ total revenue, which primarily includes treatments for rare autoimmune conditions and gout. While no blockbuster status is expected, steady cash flow from existing prescriptions supports ongoing regulatory and safety monitoring costs and maintains a defensive revenue base.

Market Expansion Opportunities and Challenges

Opportunities for growth involve:

• Enhanced Prescriber Education: Improving understanding of safety protocols could increase off-label acceptance where appropriate.
• Regulatory Modifications: Evidence supporting broader safety profiles or new formulations might facilitate revised labeling.
• Patient Advocacy and Awareness: Empowering suitable patient populations could elevate demand within the constrained market.

Challenges include:

• Safety Profile Limitations: The rare but severe adverse events continue to define prescribing constraints.
• Competition and Innovation: Emerging therapies with better safety profiles threaten market share.
• Regulatory Uncertainty: Any adverse safety reports or regulatory scolding could further restrict use and impede growth.

Future Outlook and Investment Considerations

While the prospects for exponential growth are limited, Lotronex maintains a stable, if modest, revenue stream within the specialist niche. For stakeholders, key considerations include:

• Focus on Safety Management: Safeguarding reputation through rigorous safety monitoring sustains prescriber confidence.
• Potential for Market Repositioning: If new formulations or safety data emerge, they could unlock expanded use.
• Partnerships and Licensing: Collaborations with academic institutions or biotech firms for research might enhance safety profiles or discover new applications.

Investment in Lotronex is thus characterized by stability with limited upside, conditioned heavily on regulatory and safety developments. Given the current landscape, its financial trajectory is expected to remain relatively flat, with potential for incremental growth via targeted safety improvements and prescriber education.

Key Takeaways

• Market Size is Constrained: Due to safety restrictions, Lotronex serves a small, specialized patient population.
• Regulatory and Safety Concerns Shape Dynamics: Ongoing safety issues continue to limit widespread adoption, impacting revenue.
• Competition is Intensifying: Newer therapies with favorable safety profiles are encroaching on its niche.
• Financial Performance Remains Modest: The drug generates steady but limited revenue, with growth prospects tied to safety and regulatory developments.
• Strategic Focus for Stakeholders: Emphasize risk management, explore safety data improvements, and consider niche marketing strategies to optimize financial outcomes.

FAQs

1. What are the primary safety concerns associated with Lotronex?
Lotronex has been linked to severe ischemic colitis and bowel obstruction, leading to its restricted use. These adverse events necessitate strict patient monitoring and specific prescribing protocols.

2. Has the FDA ever withdrawn Lotronex from the market?
No. After initial suspension in 2000, the FDA reapproved Lotronex in 2002 under strict REMS restrictions, allowing continued, limited use.

3. How does Lotronex’s pricing impact its market performance?
With prices ranging from $400 to $600 monthly, reimbursement complexities and formulary restrictions often limit patient access, affecting revenue potential.

4. Can Lotronex’s market grow beyond its current niche?
Limited by safety concerns and competition, significant growth depends on new safety data or regulatory modifications that broaden its indicated use.

5. Are there ongoing efforts to improve Lotronex’s safety profile?
Research and surveillance continue, but no new formulations or indications have yet emerged. Safety remains the critical factor influencing its market trajectory.

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Sources:

[1] Longstreth GF, Thompson WG, Chey WD, et al. Functional bowel disorders. Gastroenterology. 2006;130(5):1480-1491.
[2] IQVIA. U.S. Pharmaceutical Sales Data, 2022–2023.