CAYSTON Drug Patent Profile

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

Cayston is a drug marketed by Gilead and is included in one NDA.

The generic ingredient in CAYSTON is aztreonam. There are eight drug master file entries for this compound. Five suppliers are listed for this compound. Additional details are available on the aztreonam profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Cayston

A generic version of CAYSTON was approved as aztreonam by FRESENIUS KABI USA on June 18^th, 2010.

Summary for CAYSTON

US Patents:	0
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	1
Clinical Trials:	6
Drug Prices:	Drug price information for CAYSTON
What excipients (inactive ingredients) are in CAYSTON?	CAYSTON excipients list
DailyMed Link:	CAYSTON at DailyMed

See drug prices for CAYSTON

Recent Clinical Trials for CAYSTON

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

Sponsor	Phase
University of Dundee	Phase 2
Gilead Sciences	Phase 2
Children's Hospital & Research Center Oakland	Phase 4

See all CAYSTON clinical trials

US Patents and Regulatory Information for CAYSTON

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Gilead	CAYSTON	aztreonam	FOR SOLUTION;INHALATION	050814-001	Feb 22, 2010		RX	Yes	Yes

Expired US Patents for CAYSTON

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Gilead	CAYSTON	aztreonam	FOR SOLUTION;INHALATION	050814-001	Feb 22, 2010
Gilead	CAYSTON	aztreonam	FOR SOLUTION;INHALATION	050814-001	Feb 22, 2010
Gilead	CAYSTON	aztreonam	FOR SOLUTION;INHALATION	050814-001	Feb 22, 2010
Gilead	CAYSTON	aztreonam	FOR SOLUTION;INHALATION	050814-001	Feb 22, 2010

EU/EMA Drug Approvals for CAYSTON

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Gilead Sciences Ireland UC	Cayston	aztreonam	EMEA/H/C/000996Cayston is indicated for the suppressive therapy of chronic pulmonary infections due to Pseudomonas aeruginosa in patients with cystic fibrosis (CF) aged 6 years and older.Consideration should be given to official guidance on the appropriate use of antibacterial agents.	Authorised	no	no	no	2009-09-21

International Patents for CAYSTON

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

Country	Patent Number	Title	Estimated Expiration
Australia	2009233632
Hungary	E035150
Netherlands	300492
World Intellectual Property Organization (WIPO)	2005007132
Germany	122011100043
Israel	221036
Austria	502623

Supplementary Protection Certificates for CAYSTON

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1353647	SPC/GB11/049	United Kingdom		PRODUCT NAME: AZTREONAM LYSINE; REGISTERED: UK EU/1/09/543/001 20090921
1353647	2011/024	Ireland		PRODUCT NAME: AZTREONAM LYSINE; REGISTRATION NO/DATE: EU/1/09/543/001 20090923
1353647	C01353647/01	Switzerland		PRODUCT NAME: AZTREONAMLYSIN; REGISTRATION NO/DATE: SWISSMEDIC 59389 06.12.2010
1353647	1190027-1	Sweden		MARKETING AUTHORIZATION NUMBER AND DATE OF GRANT/NOTIFICATION: EU/1/09/543/001, 2009-09-23; PERIOD OF VALIDITY (FROM - UNTIL): 2021-12-21 - 2024-09- 22
1353647	300492	Netherlands		PRODUCT NAME: AZTREONAMLYSINE; REGISTRATION NO/DATE: EU/1/09/543/001 20090923
1353647	11C0030	France		PRODUCT NAME: AZTREONAM LYSINE; REGISTRATION NO/DATE IN FRANCE: EU/1/09/543/001 DU 20090921; REGISTRATION NO/DATE AT EEC: EU/1/09/543/001 DU 20090921
1353647	91851	Luxembourg		91851, EXPIRES: 20240921

Market Dynamics and Financial Trajectory for the Pharmaceutical Drug: CAYSTON

Last updated: July 28, 2025

---

Introduction

CAYSTON (aztreonam lysine for inhalation solution) holds a distinctive position within the niche segment of antibiotics designed to treat cystic fibrosis (CF) related lung infections caused by Pseudomonas aeruginosa. Since its launch, understanding its market dynamics and financial trajectory is crucial for stakeholders, including pharmaceutical companies, investors, and healthcare providers. This analysis offers a comprehensive overview of the market forces, revenue trends, competitive landscape, and future outlook for CAYSTON.

---

Product Overview and Clinical Context

CAYSTON is a nebulized antibiotic approved by the FDA in 2010 for active Pseudomonas aeruginosa lung infections in CF patients aged 7 years and older. Its targeted delivery system aims to combat a critical pathogen in CF, which significantly deteriorates patients' lung function over time. Despite its clinical niche, the drug's commercialization has faced challenges impacting sales and market penetration.

---

Market Dynamics

1. Cystic Fibrosis Prevalence and Demographics

The global CF population is estimated at approximately 90,000 patients, with a substantial portion in North America and Europe, where diagnosis and management are more advanced. In the U.S., about 30,000 individuals are diagnosed with CF, with childhood prevalence leading to consistent demand for therapies like CAYSTON [1].

2. Competitive Landscape

CAYSTON's primary competitors include inhaled antibiotics such as TOBI (tobramycin) and newer agents like BOXLYXE (newer formulations or combination therapies), each with established brand equity and wider market penetration. The emergence of combination inhaled therapies and the focus on personalized CF treatment regimens challenge CAYSTON’s exclusivity.

3. Treatment Paradigms and Clinical Adoption

The standard of care for Pseudomonas aeruginosa in CF involves chronic inhaled antibiotics. Historically, TOBI has dominated due to early entry and extensive clinical data. However, CAYSTON's niche application in specific patient subsets and its potential benefits, such as fewer adverse effects, provide unique positioning. Adoption hinges on clinicians' familiarity, reimbursement policies, and evidence of superior efficacy or safety.

4. Regulatory and Reimbursement Environment

Reimbursement remains a barrier in some markets, particularly given the high cost of inhaled antibiotics and the necessity for specialized delivery devices. Healthcare payers scrutinize clinical benefits over incremental improvements, impacting sales significantly.

5. Patent Status and Market Exclusivity

As of 2023, CAYSTON's patent protections are approaching expiry, risking generic competition. This timeline influences long-term revenue potential and strategic planning for the manufacturing companies.

---

Financial Trajectory Analysis

1. Revenue Trends

Post-approval, CAYSTON witnessed modest sales volumes, primarily driven by specialized centers and CF clinics. Reports suggest peak annual revenues around $20 million in the early 2010s (exact figures vary depending on sources) [2]. However, subsequent years show a plateau or decline, attributed to limited market penetration and competition.

2. Factors Affecting Revenue

• Market Penetration: Limited uptake due to clinician familiarity with existing therapies.
• Patient Segments: Restricted to CF patients ≥7 years, limiting eligible population.
• Chronic Use and Reimbursement: The necessity of repeated, costly inhalation therapy affects affordability and adherence.
• Competitive Pricing and Cost-Effectiveness: Pricing pressures and the availability of alternative regimens constrain revenue growth.

3. R&D and Marketing Investment

The company invested in clinical trials, post-marketing studies, and targeted marketing campaigns. The cost of these initiatives without proportionate revenue growth resulted in a challenging financial balance.

4. Strategic Options and Future Outlook

Potential strategies include combination therapies, formulation improvements, or expanded indications to extend market life. The expiration of essential patents could catalyze generic entry, sharply reducing revenues unless differentiation strategies are pursued.

---

Market Challenges and Opportunities

Challenges:

• Limited Market Penetration: Despite demonstrated efficacy, clinician hesitance and existing preferences hinder widespread adoption.
• Generic Competition Risks: Patent expiry threatens market share and profitability.
• Reimbursement Barriers: High drug costs are not always aligned with payer willingness to reimburse.
• Limited Clinical Data: Compared to established therapies, CAYSTON needs more robust comparative data to persuade clinicians.

Opportunities:

• Novel Formulation Development: Improving delivery mechanisms or combining with other CF therapies.
• Expanding Indications: Investigating efficacy in other respiratory infections or patient age groups.
• Strategic Collaborations: Partnering with biotech firms to develop combination products.
• Market Expansion: Increasing adoption in emerging markets with growing CF awareness.

---

Future Outlook

While CAYSTON's current market performance remains modest, its niche status within CF management offers potential paths for growth if strategic initiatives are implemented. Advances in inhaled antibiotic formulations, real-world evidence supporting its benefits, and expanded indications could rejuvenate its financial trajectory. However, impending patent expirations necessitate proactive measures to sustain revenue streams.

---

Key Takeaways

• Niche Positioning: CAYSTON targets a specific patient subset in CF, limiting its market size but offering potential for specialized adoption.
• Market Saturation and Competition: Established antibiotics like TOBI dominate, creating a high barrier for new entrants and limiting revenue growth.
• Revenue Plateau: Peak sales circa early 2010s have likely plateaued or declined due to competition, reimbursement issues, and limited awareness.
• Patent and Pricing Risks: Patent expiry threatens future exclusivity, urging strategic moves to extend product lifecycle.
• Growth Opportunities: Formulation improvements, combination therapies, and expanding indications are vital to improving financial prospects.

---

FAQs

Q1: What is the primary therapeutic advantage of CAYSTON over competitors?
A1: CAYSTON offers targeted inhalation therapy with potentially fewer systemic side effects compared to traditional antibiotics, and its formulation may facilitate use in specific patient populations within CF care.

Q2: How does patent expiration impact CAYSTON's market potential?
A2: Patent expiry invites generic competition, significantly reducing pricing power and revenues unless new formulations or indications are developed.

Q3: What are the main challenges hindering CAYSTON's broader adoption?
A3: Clinicians’ familiarity with existing treatments, reimbursement hurdles, high treatment costs, and limited clinical data comparing efficacy with other antibiotics.

Q4: Are there ongoing efforts to expand CAYSTON's indications?
A4: Currently, no major clinical trials are publicly announced for new indications, but future research exploring such avenues could enhance market prospects.

Q5: How can pharmaceutical companies extend the commercial viability of drugs like CAYSTON?
A5: By developing combination therapies, improving delivery mechanisms, pursuing new indications, and strengthening clinical evidence to justify reimbursement.

---

References

[1] Cystic Fibrosis Foundation. 2022 Annual Data Report. Available at: CF Foundation Data

[2] IMS Health. Pharmaceutical Sales Data. Market reports, 2012-2020.

---