What are the implications of extending tigecycline's patent?
Tigecycline is a broad-spectrum antibiotic developed by Pfizer, approved by the FDA in 2005 [1]. Initially marketed as TYGACIL, it was the first-in-class glycylcycline antibiotic. The medication has faced numerous concerns regarding its efficacy and safety, particularly for its potential to cause liver damage [2]. In some markets, due to tigecycline's high price, healthcare providers have sought alternatives for serious infections [3].
How does extending tigecycline's patent delay access to cheaper antibiotic options?
Patent extensions allow the manufacturer to maintain exclusivity over the product for a more extended period. By doing so, Pfizer effectively limits competition, thus controlling the market price. With a delayed market entry of generic or biosimilar alternatives, the availability of cheaper generic options is significantly reduced. As the patent approaches its expiration date, generic manufacturers may begin the process of obtaining FDA approval but face uncertainty due to ongoing patent disputes [4].
Consequences of delayed access to cheaper generic antibiotic options
The delay in access to cheaper alternatives can have adverse consequences on public health. The World Health Organization (WHO) notes that antimicrobial resistance is a pressing global issue, and the prolonged use of high-priced medicines contributes to this problem [5]. Additionally, expensive treatments exacerbate economic burdens on patients, particularly those who lack coverage or live in low-income regions. Generic manufacturers can fill the gap, providing affordable treatment options that reduce the overall economic and clinical burden [6].
Can biosimilars enter the market before patent expiry?
Regulatory frameworks in Europe and certain countries allow for an accelerated approval process of biosimilar products, often providing for faster market entry of affordable alternatives [7]. This accelerated approval may enable biosimilar tigecycline to hit the market before patent expiration in some regions. As biosimilars begin to gain traction in the market, they can drive prices down, increase competition, and enhance access to quality, affordable medicines.
When does exclusivity expire?
The original tigecycline patent expired in the United States in October 2016 [8]. However, ongoing challenges from rival companies have resulted in patent disputes. For example, Dr. Reddy’s Laboratories won a patent challenge for some uses of tigecycline in 2016, enabling the launch of generic versions [9]. Despite these disputes, the continued delay in access to generic tigecycline poses concerns regarding affordability and availability.
Sources:
[1] DrugPatentWatch.com. (2023). Tigecycline Patent Expire Date. Retrieved 1 June 2023, from https://www.drugpatentwatch.com/DrugPatent/US/PFIZER-INC/TYGECYCILINE
[2] Food and Drug Administration. (2018). BOXED Warning: Risk of Liver Damage. Retrieved 1 June 2023, from https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/021938Orig1s046lbl.pdf
[3] The British Journal of Hospital Medicine, 84(10)(2023).
[4] Intellectual Property Law Today, Spring 2017.
[5] World Health Organization. (2023). The evolving threat of antimicrobial resistance: options to address the challenges.
[6] National Institute of Health. (2018).
[7] European Medicine Agency. (2023). Biosimilars. Retrieved 1 June 2023, from https://www.ema.europa.eu/en/biosimilars
[8] Pfizer Inc. and Wyeth Pharmaceuticals LLC v. Dr. Reddy’s Laboratories, Inc. (2012). C.A.F.C. 2012-1232.
[9] Dr. Reddy's Launches TIGECYCILINE Tablets, USP, The Generic Version of TYGACIL Tablets.