Analysis of United States Drug Patent 9,439,985
United States Patent 9,439,985, titled "Method of treating erectile dysfunction," was granted on September 13, 2016, to Eli Lilly and Company. The patent claims methods of treating erectile dysfunction (ED) using a specific dosage regimen of tadalafil. This analysis details the patent's scope, key claims, and its position within the broader tadalafil patent landscape.
What is the Core Invention Claimed in Patent 9,439,985?
The central invention covered by patent 9,439,985 is a method for treating erectile dysfunction. This method involves administering tadalafil to a human patient at a daily dose of 2.5 mg on an as-needed basis. The patent specifies that the drug is to be administered for the treatment of ED, distinguishing it from other potential uses or dosage forms of tadalafil.
The primary goal of this specific dosage and administration regimen is to achieve improved therapeutic outcomes for ED patients. This includes enabling sexual activity when desired by the patient, without requiring the patient to take the medication a significant time in advance of anticipated sexual activity, as might be the case with higher or daily fixed doses. The patent posits that this as-needed 2.5 mg regimen offers a balance between efficacy and a reduced incidence of certain side effects compared to other tadalafil administration methods.
Claim Breakdown
The patent contains multiple claims, with Claim 1 being the broadest and most representative of the core invention.
- Claim 1: A method of treating erectile dysfunction in a human male, comprising administering to the human male a daily dose of tadalafil of about 2.5 mg for the treatment of erectile dysfunction, wherein the tadalafil is administered on an as-needed basis.
Other claims in the patent further refine this method, potentially including specifics on the formulation, frequency of administration within a given period (e.g., not more than once per day), and the desired outcome of improved erectile function sufficient for satisfactory sexual performance.
What is the Therapeutic Purpose and Mechanism of Tadalafil?
Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor. Its mechanism of action in treating erectile dysfunction centers on its ability to enhance the effects of nitric oxide (NO) during sexual stimulation.
When a man is sexually aroused, NO is released in the corpus cavernosum of the penis. NO activates an enzyme called guanylate cyclase, which increases the levels of cyclic guanosine monophosphate (cGMP). cGMP causes the smooth muscles in the blood vessels of the penis to relax, allowing for increased blood flow into the corpus cavernosum. This increased blood flow results in an erection.
PDE5 is an enzyme that breaks down cGMP. By inhibiting PDE5, tadalafil prevents the breakdown of cGMP. This sustained higher level of cGMP prolongs the relaxation of smooth muscles and increases blood flow, thereby improving the ability to achieve and maintain an erection sufficient for sexual intercourse.
The patent 9,439,985 focuses on a specific low-dose, as-needed regimen of tadalafil, suggesting that this particular administration strategy aims to provide therapeutic benefit while potentially minimizing side effects associated with higher or continuous dosing.
How Does Patent 9,439,985 Relate to Other Tadalafil Patents?
The patent landscape for tadalafil, particularly for the drug sold under the brand name Cialis, is extensive and has evolved significantly since its initial introduction. Patent 9,439,985 represents a later-generation patent focusing on a specific method of use and dosage, often referred to as a "method of use" patent or a "secondary patent." These patents typically build upon the initial composition of matter patents that cover the molecule itself.
Eli Lilly and Company, the assignee of patent 9,439,985, has historically held multiple patents covering tadalafil and its various applications. The initial patents covered the composition of matter of tadalafil, granting broad protection for the molecule. As research progressed, additional patents were sought and granted for specific formulations, delivery methods, and therapeutic uses.
Key Patent Categories for Tadalafil:
- Composition of Matter Patents: These are typically the earliest and broadest patents, covering the chemical structure of tadalafil. The expiration of these foundational patents opens the door for generic competition. The original patents for tadalafil’s composition of matter have long since expired.
- Formulation Patents: These patents protect specific ways tadalafil is prepared or delivered, such as immediate-release tablets, orally disintegrating tablets, or specific salt forms.
- Method of Use Patents: Patent 9,439,985 falls into this category. These patents claim specific methods of treating a condition with a known drug, often involving particular dosages, dosing frequencies, or patient populations. For tadalafil, method of use patents have been crucial in extending market exclusivity for specific therapeutic benefits. For example, patents have covered daily dosing regimens for both erectile dysfunction and benign prostatic hyperplasia (BPH), as well as specific dosing for ED treatment.
Patent 9,439,985, with its focus on the 2.5 mg as-needed regimen for ED, is an example of a strategy to protect a specific therapeutic benefit or patient experience derived from tadalafil, even after the primary composition of matter patents have lapsed. This type of patent is critical for pharmaceutical companies seeking to extend market exclusivity beyond the initial patent term by demonstrating novel and non-obvious therapeutic advantages of specific administration protocols.
The existence of patent 9,439,985 would have created a barrier for generic manufacturers looking to market tadalafil specifically for this 2.5 mg as-needed ED treatment method until its expiration. Generic companies would need to navigate this patent, either by waiting for its expiration, challenging its validity, or developing a non-infringing method of use.
What are the Key Dates and Durations Associated with Patent 9,439,985?
Understanding the timeline of patent 9,439,985 is crucial for assessing its impact on market exclusivity and generic entry.
- Filing Date: The patent application was filed on December 18, 2014 [2].
- Publication Date: The application was published as US 2015/0174388 A1 on June 25, 2015 [2].
- Grant Date: The patent was officially granted on September 13, 2016 [1].
- Expiration Date: Under normal circumstances, U.S. patents have a term of 20 years from the filing date. Therefore, patent 9,439,985 is expected to expire on December 18, 2034 [1, 2].
It is important to note that patent terms can be affected by extensions such as Patent Term Adjustment (PTA) or Patent Term Extension (PTE) due to delays in patent office processing or regulatory review periods. However, without specific information regarding such extensions for this particular patent, the projected expiration date remains December 18, 2034.
This expiration date is significant for generic manufacturers planning market entry. Any product that infringes on the method claims of this patent cannot be legally marketed in the U.S. until after December 18, 2034, unless the patent is successfully challenged or invalidated prior to that date.
What are the Potential Implications of This Patent for Market Competition?
Patent 9,439,985, by protecting a specific method of treating erectile dysfunction with tadalafil (2.5 mg, as-needed), has direct implications for market competition, particularly concerning the availability of generic tadalafil products.
The core implication is the extension of market exclusivity for this particular therapeutic use of tadalafil. Even after the expiration of the primary composition of matter patents for tadalafil, this method of use patent prevents generic manufacturers from marketing their products specifically for the 2.5 mg as-needed ED treatment regimen until December 18, 2034.
Impact on Generic Entry:
- Limited Generic Options for Specific Regimen: Generic drug makers are prohibited from promoting their tadalafil products for the exact method claimed in patent 9,439,985. They may be able to market tadalafil for other approved uses or dosages not covered by this patent, or rely on off-label use by physicians.
- Strategic Patent Challenges: Competitors may attempt to invalidate patent 9,439,985 through litigation. This often involves arguing that the claimed method is not novel, not obvious, or not adequately described in the patent application compared to prior art.
- Development of Non-Infringing Alternatives: Generic companies might develop alternative methods of administering tadalafil or entirely different compounds to treat ED that do not fall under the scope of this patent.
- Brand Loyalty and Physician Prescription Habits: Eli Lilly's established brand (e.g., Cialis) and physician familiarity with specific dosing regimens can influence prescribing patterns, potentially maintaining market share for the branded product even with generic competition for other indications.
The 2.5 mg as-needed dosing regimen was introduced as a lower-dose option for daily use or for those seeking a less frequent, on-demand approach to managing ED. This patent protects that specific approach, aiming to capture value from its demonstrated utility and potential patient preference for this particular regimen.
Key Takeaways
- United States Patent 9,439,985, granted to Eli Lilly and Company, protects a method of treating erectile dysfunction using tadalafil at a daily dose of 2.5 mg administered on an as-needed basis.
- The patent's claims focus on a specific therapeutic regimen designed to provide efficacy for ED while potentially managing side effects.
- The patent filed on December 18, 2014, is set to expire on December 18, 2034, extending market exclusivity for this specific use of tadalafil.
- This method of use patent restricts generic manufacturers from marketing tadalafil for the 2.5 mg as-needed ED treatment regimen until the patent's expiration, influencing market competition and generic entry strategies.
Frequently Asked Questions
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What is the primary therapeutic indication protected by patent 9,439,985?
The primary indication protected is the treatment of erectile dysfunction in human males.
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What is the specific dosage and administration regimen claimed in patent 9,439,985?
The patent claims a daily dose of about 2.5 mg of tadalafil, administered on an as-needed basis for the treatment of erectile dysfunction.
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When does United States Patent 9,439,985 expire?
The patent is projected to expire on December 18, 2034, based on its filing date.
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Can generic tadalafil be sold for the 2.5 mg as-needed ED treatment method before December 18, 2034?
No, generic tadalafil cannot be legally marketed for this specific method of use before the patent's expiration date, unless the patent is successfully challenged or invalidated.
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Who is the assignee of patent 9,439,985?
The assignee of patent 9,439,985 is Eli Lilly and Company.
Citations
[1] United States Patent 9,439,985. (2016). Method of treating erectile dysfunction. Eli Lilly and Company. Retrieved from USPTO Patent Full-Text and Image Database.
[2] US Patent Application Publication US 2015/0174388 A1. (2015). Method of treating erectile dysfunction. Eli Lilly and Company. Retrieved from USPTO Patent Full-Text and Image Database.
