United States Patent 8,648,093: Delafloxacin Meglumine Formulation Claims and Patent Landscape

U.S. Patent No. 8,648,093 protects pharmaceutical compositions and antibacterial treatment methods containing delafloxacin meglumine, including its anhydrous or unspecified salt form and trihydrate form. The claims focus on the salt, crystalline characteristics, purity thresholds, dosage-form routes, and treatment of bacterial infections in mammals and fish.

The patent is a formulation and solid-state patent, not the principal composition-of-matter patent for delafloxacin. Its commercial relevance is tied to Baxdela, the delafloxacin product marketed by Melinta Therapeutics.

What drug and salt are covered by U.S. Patent 8,648,093?

The claimed active ingredient is delafloxacin in the meglumine salt form.

Element	Identification
Active antibacterial	Delafloxacin
Salt counterion	Meglumine, also called N-methyl-D-glucamine
Claimed hydrate	Delafloxacin meglumine trihydrate
Drug class	Fluoroquinolone antibacterial
Commercial product	Baxdela
Dosage forms	Oral and parenteral
Patent	U.S. 8,648,093 B2
Issue date	February 11, 2014
Patent owner associated with development	Rib-X Pharmaceuticals, later Melinta Therapeutics
FDA approval	June 19, 2017, NDA 208610

The chemical name in the claims identifies the delafloxacin anion and the D-glucitol, 1-deoxy-1-(methylamino)- cation. That cation is meglumine. The claims therefore do not cover every delafloxacin salt. They are directed to delafloxacin meglumine and, in claims 14 through 26 and 30 through 32, specifically to its trihydrate.

FDA approved Baxdela for acute bacterial skin and skin-structure infections and later for community-acquired bacterial pneumonia in adults. The approved product includes intravenous and oral presentations. [1]

What is the scope of claims 1 through 13?

Claims 1 through 13 cover compositions containing delafloxacin meglumine, an excipient from the specified Markush list, and selected physical or pharmaceutical properties.

Independent composition claim 1

Claim 1 requires:

Delafloxacin meglumine;
A therapeutic composition; and
At least one listed excipient or a mixture of listed excipients.

The excipient list is extensive. It includes common pharmaceutical materials such as:

Lactose
Mannitol
Microcrystalline or other cellulose
Povidone
Crospovidone
Magnesium stearate
Sodium carboxymethyl cellulose
Hydroxypropylmethyl cellulose
Starch
Sucrose
Water
Ethanol
Propylene glycol
Oils
Surfactants
Gelatin
Talc

The claim is broad with respect to dosage-form composition because it does not limit the drug to a particular tablet, capsule, vial, concentration, or manufacturing process. It does, however, require the claimed salt and at least one excipient in the recited group.

Dependent claim structure

Claims	Subject matter
1	Delafloxacin meglumine composition with listed excipient
2	Therapeutically acceptable amount
3	Crystalline salt
4-5	Substantial crystalline purity, including at least about 95%
6	Powder diffraction pattern shown in Figure 1
7	Specific monoclinic lattice parameters
8-11	Chemical purity, approximately 97%, 98%, or 100%
12	Oral dosage form
13	Parenteral dosage form

Claims 3 through 7 narrow the scope from a composition containing the salt to a defined crystalline form. Claims 8 through 11 address chemical purity rather than crystal-form purity. Those concepts are separate: a material can have high chemical purity without satisfying the claimed crystalline-form limitations.

What is the scope of claims 14 through 26?

Claims 14 through 26 repeat the structure of claims 1 through 13 but specify delafloxacin meglumine trihydrate.

The trihydrate limitation is commercially important because hydrates can have different:

Water content
Powder-flow properties
Dissolution behavior
Hygroscopicity
Stability
Manufacturing characteristics
Solid-state conversion risks

Claim 14 is the independent trihydrate composition claim. It requires delafloxacin meglumine trihydrate, a therapeutic composition, and at least one listed excipient.

Crystalline trihydrate limitations

Claims 16 through 20 address crystalline trihydrate. Claim 19 refers to the powder diffraction pattern shown in Figure 2. Claim 20 recites lattice parameters of approximately:

Parameter	Claimed value
a	8.2490 Å
b	29.9840 Å
c	12.5070 Å
β	About 105°
Crystal system	Monoclinic
Space group	P21/C or P21/M

These limitations create a solid-state fingerprint. A competing product containing delafloxacin meglumine trihydrate would require structural characterization, including XRPD and potentially single-crystal or unit-cell analysis, to assess infringement.

What do claims 27 through 32 protect?

Claims 27 through 32 are method-of-treatment claims.

They cover treating a bacterial infection in:

A fish; or
A mammal,

by administering a composition containing delafloxacin meglumine or delafloxacin meglumine trihydrate, together with an excipient from the listed group.

Claim 28 narrows the method to administration to a mammal. Claims 29 and 32 specify a dose range of approximately 0.03 to 200 mg/kg body weight.

Method claim limitations

Claim group	Salt	Patient or animal	Dose limitation
27-29	Delafloxacin meglumine	Fish or mammal; claim 28 mammal only	0.03-200 mg/kg in claim 29
30-32	Delafloxacin meglumine trihydrate	Fish or mammal; claim 31 mammal only	0.03-200 mg/kg in claim 32

The method claims are not limited to a named bacterial species, infection site, treatment duration, or administration frequency. A product or clinical protocol using the claimed salt, excipient, and dose range could raise infringement issues if the remaining claim limitations are met.

How broad is the excipient limitation?

The excipient limitation is broad in substance but narrow in legal form.

It is broad because the list covers most conventional pharmaceutical excipient categories. It is narrow because the claim uses a closed Markush formulation: an accused composition must contain an excipient selected from the recited group or a mixture of those materials.

A formulation containing a materially different excipient not reasonably falling within the listed categories may avoid literal infringement of claim 1 or claim 14. The analysis would depend on the identity and function of the excipient and on any applicable doctrine-of-equivalents argument.

The claims do not require a specific ratio between delafloxacin meglumine and excipient. They also do not require a particular dosage strength, tablet weight, vial concentration, dissolution profile, release profile, or manufacturing process.

What are the key claim-construction issues?

Does “salt” cover salts other than meglumine?

The chemical name identifies the cation as D-glucitol, 1-deoxy-1-(methylamino)-, which is meglumine. A conventional reading limits the claim to the delafloxacin meglumine salt rather than delafloxacin sodium, potassium, hydrochloride, or another salt.

What does “crystalline purity” mean?

Claims 4, 5, 17, and 18 use “substantial crystalline purity” and “at least about 95% crystalline purity.” The patent specification and analytical methods would be important in determining whether this refers to the percentage of the claimed polymorph, total crystallinity, or another XRPD-based measurement.

How important are the XRPD figures?

Claims 6 and 19 incorporate the diffraction patterns shown in Figures 1 and 2. In litigation, the figure-based limitations would typically be compared with a reference diffraction pattern using peak positions, relative intensities, experimental tolerances, and the measurement conditions recited in the claims.

What is the effect of “about”?

The lattice parameters and dose range use “about.” The allowable deviation would ordinarily be interpreted in light of the specification, measurement precision, scientific convention, and prosecution history.

Are oral and parenteral claims separate?

Yes. Claims 12, 13, 25, and 26 expressly distinguish oral and parenteral administration. A tablet, capsule, oral suspension, injection, or infusion product may satisfy different dependent claims depending on its formulation and route.

What patent protects the underlying delafloxacin molecule?

The principal composition-of-matter protection for delafloxacin is separate from U.S. Patent 8,648,093. The core delafloxacin patent family includes U.S. Patent No. 7,935,698, which covers quinolone antibacterial compounds including delafloxacin-related chemical subject matter.

The distinction is material:

Protection layer	Typical subject matter	Relevance
Core compound patent	Delafloxacin molecule and related quinolones	Blocks manufacture and use of the active molecule
Salt patent	Meglumine salt or specific salt forms	Blocks particular pharmaceutical salt forms
Solid-state patent	Crystalline form, hydrate, polymorph	Blocks particular physical forms
Formulation patent	Excipients and dosage forms	Blocks specified finished-product compositions
Method patent	Treatment of bacterial infections	Blocks specified therapeutic use

A generic manufacturer can face different risks depending on whether it uses delafloxacin free acid, a different salt, an anhydrous form, or the claimed trihydrate.

When does U.S. Patent 8,648,093 lose exclusivity?

The patent issued on February 11, 2014. Its nominal term is expected to run into 2030 based on the underlying U.S. or international filing timeline, subject to any patent-term adjustment, patent-term extension, terminal disclaimer, or later legal event recorded by the USPTO.

The patent term cannot be determined solely from the issue date or the claim text. For commercial diligence, the controlling record is the USPTO Patent Center term calculation and any terminal-disclaimer or PTA/PTE entries.

Regulatory exclusivity is separate from patent term. FDA approved delafloxacin in 2017 and granted Qualified Infectious Disease Product treatment under the Generating Antibiotic Incentives Now framework. QIDP treatment can add five years to applicable exclusivity and patent-term benefits, but it does not automatically extend every patent covering the product. [1, 2]

What is the Orange Book status of U.S. Patent 8,648,093?

Patent listing is NDA-specific. A patent number is not automatically an Orange Book-listed patent merely because it covers a drug formulation.

For Baxdela, the relevant Orange Book analysis requires checking:

NDA 208610;
The listed product strength and dosage form;
Whether U.S. 8,648,093 is listed against the tablet, injection, or both;
The use code associated with any method claim;
Any delisting, expiration, or certification history;
Whether the listing was timely submitted under FDA patent-listing rules.

FDA’s Orange Book identifies patents and exclusivity associated with approved products, but it does not decide infringement or validity. [3]

Are Paragraph IV challenges likely against this patent?

A generic applicant seeking approval before patent expiration could file an ANDA with a Paragraph IV certification if it contends that U.S. 8,648,093 is invalid, unenforceable, or not infringed. The likely design-around and challenge positions would include:

Use of delafloxacin free acid or a non-meglumine salt.
Use of a non-trihydrate form.
Use of an amorphous or different crystalline form.
Use of an excipient outside the listed Markush group.
Avoidance of the claimed dose range.
Challenge to the XRPD or lattice-parameter limitations.
Obviousness based on known delafloxacin, meglumine salts, hydrates, and routine pharmaceutical formulation practice.
Lack of written description or enablement for the breadth of the excipient and dosage-form claims.

A Paragraph IV challenge to a listed patent can trigger a 45-day infringement period and, under the Hatch-Waxman framework, a potential 30-month stay of FDA approval, subject to statutory exceptions and litigation developments. [2]

How strong is the patent estate?

The estate is strongest against a product that reproduces the commercial salt and solid form. It is weaker against a product that changes the salt, hydrate state, crystal form, or formulation architecture.

Risk area	Relative risk
Delafloxacin meglumine trihydrate in a conventional formulation	High
Delafloxacin meglumine with listed excipient	High to moderate
Delafloxacin free acid	Lower under this patent, subject to other patents
Alternative delafloxacin salt	Lower under this patent
Different polymorph or amorphous form	Moderate to lower
Formulation using unlisted excipients	Potentially lower
Veterinary use in fish or mammals	Covered by method claims if all limitations are met
Oral Baxdela-like tablet	High
Intravenous Baxdela-like product	High

The patent’s principal vulnerability is breadth. The excipient list is extensive, the claims cover both oral and parenteral products, and the method claims cover a wide animal population and dose range. Those features create potential written-description, enablement, anticipation, and obviousness challenges.

Its principal strength is the combination of chemical identity and solid-state limitations. A competitor cannot avoid the crystalline-form claims merely by using a different excipient if its active ingredient still satisfies the claimed salt and structural parameters.

Which companies are challenging delafloxacin exclusivity?

The relevant competitive group includes:

Generic fluoroquinolone manufacturers evaluating delafloxacin ANDA entry;
Contract manufacturers capable of producing sterile injectable delafloxacin;
Companies developing alternative agents for acute bacterial skin infections and community-acquired bacterial pneumonia;
Biosimilar developers, although biosimilar pathways do not apply to delafloxacin because it is a chemically synthesized small molecule.

Publicly identified litigation or settlement activity must be confirmed through PACER, FDA Paragraph IV notices, USPTO records, and Orange Book history. A biosimilar challenge is not legally relevant to this product. The principal regulatory pathway for a competing small-molecule product is an ANDA, with a 505(b)(2) application possible for certain reformulations or alternative salts. [3, 4]

What manufacturing and IP barriers remain?

The key manufacturing barriers are:

Control of delafloxacin meglumine salt formation;
Reproducible production of the claimed trihydrate;
Prevention of conversion between hydrate and anhydrous forms;
Control of XRPD profile and residual water;
Stability during tablet compression and storage;
Sterile manufacture for the intravenous product;
Bioequivalence for oral products;
Comparative dissolution and impurity control.

An ANDA applicant would need to establish pharmaceutical equivalence and bioequivalence to the relevant reference product. A formulation that avoids literal infringement may still face regulatory complexity if it produces a different solid form or release profile.

What licensing and ownership history affects the patent?

Delafloxacin was developed by Rib-X Pharmaceuticals. Rib-X changed its name to Melinta Therapeutics, and Melinta became the commercial sponsor associated with Baxdela. The company later underwent ownership changes, including transactions involving The Medicines Company and subsequent ownership by Eurofarma.

Ownership changes do not alter the patent claims, but they affect:

Royalty obligations;
Patent enforcement authority;
FDA sponsor records;
Licensing rights;
Settlement authority;
Assignment-chain diligence.

Any transaction involving delafloxacin should review the USPTO assignment database, FDA sponsor history, development agreements, and royalty or commercialization arrangements.

Key Takeaways

U.S. Patent 8,648,093 covers delafloxacin meglumine pharmaceutical compositions and bacterial-infection treatment methods.
Claims 14 through 26 and 30 through 32 specifically target delafloxacin meglumine trihydrate.
The patent combines salt identity, excipient selection, crystalline form, XRPD pattern, lattice parameters, purity, route, and dose limitations.
It is distinct from the core delafloxacin composition-of-matter patent.
The highest infringement risk involves Baxdela-like oral or intravenous products using delafloxacin meglumine trihydrate.
Alternative salts, polymorphs, amorphous forms, and formulations using materially different excipients present stronger design-around positions.
Patent expiration, Orange Book listing, and Paragraph IV exposure must be assessed from the current USPTO and FDA records rather than the claim text alone.
Delafloxacin is a small molecule, so biosimilar litigation is not applicable.

FAQs

Is U.S. Patent 8,648,093 a composition-of-matter patent?

No. It is primarily a salt, crystalline-form, formulation, and method-of-treatment patent. The underlying delafloxacin molecule is protected by separate patent families.

Does the patent cover delafloxacin hydrochloride or delafloxacin sodium?

The claims identify the meglumine cation. They do not ordinarily cover unrelated delafloxacin salts such as hydrochloride or sodium salts.

Does using a different excipient avoid infringement?

Not necessarily. A different excipient may avoid the literal closed-list limitation, but the active salt, hydrate, crystalline form, and other claim elements must also be evaluated.

Can a generic use delafloxacin before the patent expires?

A generic applicant may file an ANDA and challenge the patent through a Paragraph IV certification. Commercial launch before expiration would depend on litigation, settlement, patent validity, non-infringement, regulatory exclusivity, and any applicable court order.

Are delafloxacin biosimilars possible?

No. Delafloxacin is a chemically synthesized small molecule. Competing products would generally proceed through the ANDA or, in selected cases, 505(b)(2) pathway rather than the biosimilar pathway.

References

U.S. Food and Drug Administration. (2017). Baxdela (delafloxacin meglumine) prescribing information.
U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act, 21 U.S.C. § 355 and 35 U.S.C. §§ 156, 271, 282.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
U.S. Food and Drug Administration. (n.d.). 505(b)(2) applications.
U.S. Patent and Trademark Office. (2014). U.S. Patent No. 8,648,093, Delafloxacin meglumine formulations.
U.S. Patent and Trademark Office. (n.d.). Patent Center and patent term adjustment records.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Canada	2582954	⤷ Start Trial
Cyprus	1125048	⤷ Start Trial
Denmark	3056492	⤷ Start Trial
European Patent Office	1802607	⤷ Start Trial
European Patent Office	3056492	⤷ Start Trial
European Patent Office	3957632	⤷ Start Trial
Spain	2901955	⤷ Start Trial
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Details for Patent: 8,648,093

Summary for Patent: 8,648,093