United States Patent 9,393,203: Treprostinil Osmotic Delivery Claims, Patent Scope, and Market-Entry Risk
U.S. Patent No. 9,393,203 protects oral osmotic dosage forms containing a highly water-soluble pharmaceutically acceptable treprostinil salt, principally treprostinil diethanolamine, combined with a defined solid surfactant release enhancer. The patent also covers pulmonary-hypertension treatment methods using those dosage forms and pharmacokinetic profiles maintained for approximately two to eight hours.
The patent is assigned to United Therapeutics Corporation and is directed to the extended-release oral treprostinil product Orenitram. Its principal commercial vulnerability is narrow formulation design-around rather than direct substitution with an ordinary immediate-release or non-osmotic tablet.
What does U.S. Patent 9,393,203 protect?
The patent protects four linked technical elements:
- An oral solid dosage form.
- An osmotic delivery composition or osmotic drug core.
- A pharmaceutically acceptable treprostinil salt with aqueous solubility of at least approximately 30 mg/mL.
- A solid surfactant release enhancer selected from five specified compounds.
The listed surfactants are:
- Polysorbate 20
- Polysorbate 60
- Polysorbate 80
- Sodium lauryl sulfate
- Sodium docusate
The broadest independent formulation claims are claims 1 and 14. Claims 4 and 18 are method-of-treatment claims directed to oral treatment of pulmonary hypertension.
Patent identification
| Field |
Information |
| Patent |
U.S. Patent No. 9,393,203 |
| Title |
Osmotic delivery of treprostinil |
| Patent holder |
United Therapeutics Corporation |
| Issue date |
July 19, 2016 |
| Active ingredient |
Treprostinil salt |
| Principal salt |
Treprostinil diethanolamine |
| Dosage form |
Solid oral dosage form |
| Delivery technology |
Osmotic delivery through a semipermeable membrane |
| Therapeutic use |
Pulmonary hypertension |
| Commercial product association |
Orenitram extended-release tablets |
| Key formulation excipients |
Sodium lauryl sulfate, sodium docusate, or specified polysorbates |
How are the independent claims structured?
Claim 1: osmotic membrane formulation
Claim 1 requires all of the following:
- A solid dosage form.
- An oral osmotic pharmaceutical delivery composition.
- An osmotically active drug core.
- A semipermeable membrane surrounding the core.
- A treprostinil salt with water solubility of at least approximately 30 mg/mL.
- At least one listed solid surfactant release enhancer.
- Osmotic delivery of treprostinil from the core.
The claim does not cover every oral treprostinil product. It requires a specific osmotic architecture and a defined class of surfactants.
A product containing treprostinil diethanolamine in a conventional hydrophilic matrix tablet would not literally satisfy the membrane limitation. A product using a semipermeable membrane but no listed surfactant would not literally satisfy the release-enhancer limitation.
Claim 14: functional osmotic composition claim
Claim 14 is broader in structure than claim 1 because it does not expressly require the drug core to be surrounded by a semipermeable membrane. It requires:
- A solid dosage form.
- An oral osmotic pharmaceutical composition.
- A therapeutically effective amount of a highly water-soluble treprostinil salt.
- One of the listed surfactants.
- A plasma-concentration result lasting approximately two to eight hours.
Claim 14 therefore shifts part of the claim analysis from physical structure to functional performance. A competing product may avoid claim 1 by omitting the membrane architecture but still face claim 14 if it is characterized as an oral osmotic composition and produces the specified pharmacokinetic result.
Claims 4 and 18: method-of-treatment claims
Claims 4 and 18 cover oral administration of the claimed dosage forms to a human subject with pulmonary hypertension.
These claims are narrower than a general method claim covering oral treprostinil. The administered product must itself satisfy the formulation limitations incorporated from claim 1 or claim 14.
What are the dependent-claim limitations?
| Claims |
Added limitation |
| 2, 16 |
Sodium lauryl sulfate |
| 3 |
At least one osmotic agent |
| 5, 8, 17, 19 |
Treprostinil diethanolamine |
| 6, 9 |
Effective plasma concentration for approximately two to eight hours |
| 7, 15 |
Sodium lauryl sulfate or sodium docusate |
| 10, 20 |
Minimum plasma concentration of 0.1 to 0.2 ng/mL |
| 11, 21 |
Maximum plasma concentration of 0.5 to 2 ng/mL |
| 12, 22 |
Once-daily or twice-daily administration |
| 13, 23 |
Twice-daily administration |
Claim 17 repeats the treprostinil-diethanolamine limitation from claim 8 and appears redundant as presented. The issued patent should control any analysis of claim dependency and prosecution amendments.
What formulations are protected by U.S. Patent 9,393,203?
The strongest literal coverage is directed to an osmotic tablet containing treprostinil diethanolamine and sodium lauryl sulfate.
A formulation is most exposed when it has the following profile:
| Feature |
Infringement significance |
| Treprostinil diethanolamine |
Satisfies the preferred salt limitation |
| Aqueous solubility of at least 30 mg/mL |
Required by claims 1 and 14 |
| Osmotically active core |
Required by claim 1 |
| Semipermeable membrane |
Required by claim 1 |
| Sodium lauryl sulfate |
Directly satisfies claims 2 and 16 |
| Sodium docusate |
Directly satisfies claims 7 and 15 |
| Polysorbate 20, 60, or 80 |
Falls within claim 1 and claim 14 |
| Osmotic agent |
Narrows into claim 3 |
| Two- to eight-hour plasma exposure |
Narrows into claims 6, 9, 14, and 18-23 |
| Twice-daily dosing |
Narrows into claims 13 and 23 |
The claims are not limited to a particular tablet strength, treprostinil dose, membrane thickness, pore former, osmotic agent, or tablet geometry unless those limitations appear elsewhere in the patent specification or prosecution history.
How strong is the patent estate for Orenitram?
Patent 9,393,203 is one component of a broader United Therapeutics patent family covering oral treprostinil. The estate includes formulation, osmotic delivery, dosage regimen, and product-specific protection associated with Orenitram.
The relevant protection should be separated into four categories:
Core compound protection
Treprostinil itself is an older prostacyclin analog. Patent 9,393,203 does not function primarily as a new chemical entity patent. Its value lies in delivery of treprostinil through an oral extended-release system.
Osmotic delivery protection
The patent's principal technical barrier is the combination of:
- Highly soluble treprostinil salt.
- Solid surfactant.
- Osmotic delivery.
- Semipermeable membrane, for the claims that require it.
This combination is more defensible than a claim directed only to oral treprostinil, because the formulation must reproduce a particular delivery mechanism.
Formulation-excipient protection
The surfactant Markush group is central. Sodium lauryl sulfate and sodium docusate receive additional dependent-claim protection. A generic developer using one of the listed surfactants faces a straightforward claim-mapping exercise.
The excipient claims also create a potential design-around path. A developer may investigate a different release enhancer, a matrix system, ion-exchange technology, a multiparticulate system, or a non-osmotic extended-release platform.
Pharmacokinetic protection
The two- to eight-hour effective concentration period and plasma concentration ranges add performance limitations. These limitations can strengthen infringement allegations if clinical or bioequivalence data show the claimed profile.
They can also complicate enforcement. Pharmacokinetic limitations require reliable evidence concerning formulation performance, dose, sampling intervals, food effect, patient variability, and the meaning of "therapeutically effective."
When does U.S. Patent 9,393,203 lose exclusivity?
The patent issued in 2016 and is subject to the modern patent-term framework based principally on the earliest effective nonprovisional filing date for the relevant family, subject to patent-term adjustment, terminal disclaimers, and any patent-term extension.
The patent's expected statutory term runs into approximately 2030 based on the family’s filing history. The controlling expiration date should be taken from the USPTO patent-term data and the FDA Orange Book listing, not calculated solely from the issue date.
FDA regulatory exclusivity is separate from patent exclusivity. Orenitram received FDA approval in December 2013. Its orphan-drug exclusivity period was distinct from the patent term and did not eliminate later patent protection. The product also received new-drug exclusivity associated with the approval of the NDA. FDA exclusivity does not prevent patent litigation after the regulatory exclusivity period ends.[1][2]
What is the Orange Book status of Orenitram patents?
Orenitram is an FDA-approved extended-release oral treprostinil product marketed by United Therapeutics. FDA Orange Book listings have included patents associated with Orenitram’s formulation and delivery technology, including U.S. Patent No. 9,393,203.[2]
An Orange Book listing can trigger the Hatch-Waxman certification framework when an ANDA applicant seeks approval for a product referencing the listed drug. A generic applicant may certify that:
- The listed patent has expired.
- The generic will not launch until patent expiration.
- The patent is not infringed.
- The patent is invalid or unenforceable.
A Paragraph IV certification can create a statutory patent-infringement action if the NDA holder sues within the statutory period. The filing of a Paragraph IV notice does not itself establish invalidity or noninfringement.[3]
Which companies are challenging Orenitram patents?
Publicly available information should be reviewed for each ANDA, Paragraph IV notice, and district-court docket. The claim set supplied does not identify a challenger, litigation number, settlement, or court decision.
No company should be treated as a confirmed Paragraph IV challenger solely because it has a treprostinil product, an ANDA, or a competing pulmonary-hypertension therapy. A confirmed challenge requires a filed notice, FDA disclosure, or court record.
What patent litigation affects U.S. Patent 9,393,203?
The principal litigation risk would arise from an ANDA applicant seeking approval for a generic Orenitram product. The likely causes of action would involve:
- Direct infringement of formulation claims.
- Induced infringement of method claims.
- Invalidity based on anticipation or obviousness.
- Written-description and enablement challenges.
- Claim-construction disputes over "osmotic pharmaceutical composition."
- Disputes over the 30 mg/mL solubility threshold.
- Disputes over whether the surfactant must remain chemically or physically present in the final dosage form.
- Disputes over whether the accused product achieves the claimed plasma profile.
The supplied information does not establish a particular lawsuit, settlement agreement, consent judgment, or launch date. Patent litigation status cannot be inferred from the claims alone.
What Paragraph IV defenses are available?
Noninfringement
A generic developer could design around one or more required elements:
- Use a non-osmotic matrix tablet.
- Omit the semipermeable membrane.
- Use a release enhancer outside the five listed surfactants.
- Use a treprostinil form with a different solubility profile.
- Use a product that does not produce the claimed pharmacokinetic range.
- Use a dosage regimen outside the twice-daily limitation of claims 13 and 23.
Invalidity
Potential invalidity theories include:
- Anticipation by prior oral or osmotic treprostinil formulations.
- Obviousness based on combining known osmotic delivery systems with known treprostinil salts and surfactants.
- Lack of written description for the full surfactant genus or the pharmacokinetic ranges.
- Lack of enablement across the full range of salts, surfactants, osmotic agents, and dosage forms.
- Indefiniteness involving "therapeutically effective plasma concentration" or the approximately two- to eight-hour period.
The strength of these defenses depends on the full specification, prosecution history, cited prior art, expert testing, and claim construction.
What generic launch scenarios exist?
Scenario 1: no Paragraph IV challenge
A generic applicant may file a Paragraph III certification and wait for the relevant patents to expire. This creates the lowest litigation risk but delays commercial entry.
Scenario 2: early Paragraph IV challenge
The applicant may argue that its dosage form is non-osmotic, uses a non-listed enhancer, or does not meet the solubility and pharmacokinetic limitations. United Therapeutics could seek a 30-month stay of FDA approval if statutory requirements are satisfied.[3]
Scenario 3: formulation substitution
A competitor may commercialize an alternative oral treprostinil product that uses a different controlled-release mechanism. Such a product could compete clinically without directly copying the claimed osmotic architecture.
Scenario 4: authorized or licensed generic
A settlement or license could permit an earlier launch date. The supplied claim information does not establish any settlement agreement or license involving U.S. Patent 9,393,203.
How does this patent compare with competing treprostinil products?
| Product |
Active ingredient |
Route |
Relevance to Patent 9,393,203 |
| Orenitram |
Treprostinil diethanolamine |
Oral extended release |
Primary product associated with the patent |
| Remodulin |
Treprostinil |
Subcutaneous or intravenous infusion |
Generally outside the oral osmotic dosage-form claims |
| Tyvaso |
Treprostinil |
Inhaled |
Generally outside the solid oral dosage-form claims |
| Generic oral treprostinil |
Treprostinil salt or other form |
Oral |
Risk depends on osmotic architecture, surfactant, solubility, and pharmacokinetics |
The patent does not cover inhaled or infused treprostinil products merely because they contain the same active moiety. Its strongest commercial relevance is to oral extended-release competition.
What manufacturing and intellectual-property barriers exist?
A competing manufacturer must reproduce more than the active ingredient. The principal technical barriers include:
- Uniform incorporation of a highly soluble treprostinil salt.
- Control of osmotic drug-core composition.
- Consistent surfactant distribution.
- Semipermeable membrane coating.
- Control of membrane permeability and release rate.
- Stability of treprostinil and excipients.
- Bioequivalence against Orenitram.
- Demonstration of an acceptable food-effect profile.
- Avoidance of listed patent claims.
Manufacturing-process patents, tablet-coating patents, analytical methods, and process know-how may create additional barriers even where a competitor avoids literal infringement of Patent 9,393,203.
What is the commercial exposure from Patent 9,393,203?
The patent is commercially significant because it is directed to the formulation platform for oral treprostinil, rather than to an incidental manufacturing step. A successful generic or follow-on oral product could compete directly with Orenitram.
Revenue exposure depends on:
- Orenitram’s annual net sales.
- The number of approved generic strengths.
- The timing of generic entry.
- Substitution rates.
- Managed-care coverage.
- Physician preference for oral versus inhaled or infused treprostinil.
- Whether a competitor launches an equivalent osmotic product or a non-infringing alternative.
Patent-specific revenue cannot be assigned from the claims alone. United Therapeutics reports product revenue in its annual and quarterly filings, while FDA records identify regulatory exclusivity and Orange Book listings.[2][4]
Key Takeaways
- U.S. Patent 9,393,203 covers oral osmotic treprostinil formulations and related pulmonary-hypertension treatment methods.
- The core claim combination is a highly soluble treprostinil salt, a specified solid surfactant, and an osmotic delivery system.
- Treprostinil diethanolamine with sodium lauryl sulfate is the highest-risk formulation profile for literal infringement.
- Claims 1 and 14 are the principal formulation claims; claims 4 and 18 are the principal method claims.
- Claims 6, 9, and 14-23 add pharmacokinetic and dosing limitations.
- A conventional non-osmotic matrix tablet may avoid claim 1 but requires separate analysis under claim 14.
- The patent’s expected term extends into approximately 2030, subject to USPTO term adjustments and family-specific conditions.
- Orenitram’s FDA exclusivity and patent exclusivity are separate legal protections.
- The strongest generic design-around opportunities involve a non-osmotic delivery platform, a non-listed release enhancer, or a different pharmacokinetic profile.
- Confirmed Paragraph IV challenges, litigation outcomes, and settlements require review of FDA and court records.
FAQs About U.S. Patent 9,393,203
Does Patent 9,393,203 cover all oral treprostinil tablets?
No. The claims require an osmotic composition, specified surfactant coverage, a highly soluble treprostinil salt, or the claimed pharmacokinetic characteristics.
Is treprostinil diethanolamine specifically claimed?
Yes. Treprostinil diethanolamine appears in dependent claims, including claims 5, 8, 17, and 19.
Can a generic use sodium lauryl sulfate?
Use of sodium lauryl sulfate creates substantial claim risk because it is expressly recited in dependent claims and included in the independent-claim surfactant groups.
Does the patent cover Tyvaso or Remodulin?
The claims are directed to solid oral osmotic dosage forms and oral administration. Inhaled Tyvaso and infused Remodulin do not ordinarily satisfy those dosage-form limitations.
Can a non-osmotic oral treprostinil product launch before patent expiration?
Potentially, but the product would require a claim-by-claim noninfringement analysis, including claim 14’s composition and pharmacokinetic limitations and any separate Orenitram patents.
References
- U.S. Food and Drug Administration. (2013). Orenitram (treprostinil) extended-release tablets: Prescribing information.
- U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
- 21 U.S.C. § 355(j). Abbreviated new drug applications and patent certifications.
- United Therapeutics Corporation. (2023). Annual report on Form 10-K.
- United States Patent and Trademark Office. (2016). U.S. Patent No. 9,393,203: Osmotic delivery of treprostinil.
