MXPA06010489A - Trihemihydrate, anhydrate and hydrate forms of cefdinir - Google Patents

Abstract

The present invention relates to trihemihydrate, novel lower hydrate and anhydrate forms of 7-[2-(2-aminothiazol -4-yl)-2-hydroxyiminoacetamide]-3-vinyl-3-cephem -4-carboxylic acid (syn isomer), methods for their preparation, and pharmaceutical compositions comprising these forms.

Description

FORMS OF TRIHEMIHYDRATE, ANHYDRATE AND HYDRATE OF CEFDINIR Technical Field The present invention relates to trihemihydrate, anhydride and new lower hydrate forms of 7- [2- (2-aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen-4-carboxylic acid (syn isomer), methods for their preparation, and pharmaceutical compositions comprising the new forms.

BACKGROUND OF THE INVENTION The antimicrobial agent of 7- [2- (2-aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen-4-carboxylic acid (syn isomer) (hereinafter referred to as as "Cefdinir") is a semi-synthetic oral antibiotic in the cephalosporin family. Cefdinir is sold in the United States as Omnicef® in oral suspension and capsule forms. Omnicef® is active against a broad spectrum of bacteria, including Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Hemophilus influenzae, Moraxella catarrhalis, E. coli, Klebsiella, and Proteus mirabilis. The preparation of Cefdinir was first described in the US Patent. Serial No. 4,559,334, issued December 17, 1985, while the preparation of the commercially available form of Cefdinir (Crystal A or Form I) was first described in U.S. Pat. Serial No. 4,935,507, granted on June 19, 1990, both are incorporated in such a way for reference in their entirety. Hydrates are important classes of pharmaceutical solids with different thermodynamic and chemical stability. These properties are important criteria when pharmaceutical forms of a compound are selected. The present invention provides forms of trihemihydrate, anhydrate and new lower hydrate of Cefdinir as well as pharmaceutical compositions and uses thereof. Pharmaceutical compositions comprising these forms of cefdinir and its salts and esters are useful in the treatment of bacterial infections such as Streptococcus pneumoniae and Hemophilus influenzae.

Brief Description of the Figures Figure 1 is the single crystal X-ray diffraction pattern of a cefdinir trihemihydrate form. Figure 2 is the powder X-ray diffraction pattern of a cefdinir trihemihydrate form. Figure 3 is the single crystal X-ray diffraction pattern of a cefdinir lower hydrate form. Figure 4 is the powder X-ray diffraction pattern of a lower hydrate form of cefdinir. Figure 5 is the powder X-ray diffraction pattern of cefdinir anhydrate. Figure 6 shows two powder X-ray diffraction models of two forms of cefdinir lower hydrate. Figure 7 is the DMSG analysis showing the Cefdinir Hydrate Desorption Isotherm.

Brief Description of the Invention The present invention describes the forms of trihemihydrate, anhydrate and others of lower iso-structural hydrate of Cefdinir. In one embodiment, the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (approximately 14% by weight of water), with a maximum characteristic value in the powder X-ray diffraction pattern. (model PXRD, hereinafter) at a value of two theta of 5.4 + 0.1 X In another embodiment the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (about 14% in water weight), with a maximum characteristic value in the PXRD model at a value of two theta of 10.7 + 0.1 °. In another embodiment, the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (approximately 14% by weight of water), with a maximum characteristic value in the PXRD model at a value of two theta. of 14.2 + 0.1 X In another embodiment the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (about 14% by weight of water), with a maximum characteristic value in the PXRD model at a value of two theta of 1 5.2 + 0.1 °. In another embodiment, the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (approximately 14% by weight of water), with a maximum characteristic value in the PXRD model at a value of two theta. of 21 .4 + 0.1 °. In another embodiment, the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (approximately 14% by weight of water), with a maximum characteristic value in the PXRD model at a value of two theta. of 29.2 + 0.1 °. In another embodiment, the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (approximately 14% by weight of water), with a maximum characteristic value in the PXRD model at a value of two theta. of 30.6 + 0.1 °. In yet another embodiment the present invention describes a new crystal form of Cefdinir trihemihydrate with 3.5 moles of water per molecule of Cefdinir (about 14% by weight of water), and characteristic maximum values in the PXRD model at two theta values of 5.4 + 0.1 °, 10.7 ± 0.1% 14.2 + 0.1 °, 1 5.2 + 0.1 °, 21.4 + 0.1 °, 29.2 + 0.1 °, and 30.6 + 0.1 ° In another embodiment the present invention describes hydrate crystal forms lower isostructural of Cefdinir with a water content of 1.7% to 6.1% water by weight.A lower hydrate of the present invention has a characteristic maximum value in the PXRD model at a value of two theta of 6.0 + 0.1 ° In another embodiment, the present invention describes a lower hydrate with a characteristic maximum value in the PXRD model at a value of two theta of 8.0 + 0.1 ° In another embodiment the present invention describes a lower hydrate with a maximum characteristic value in the mod. elo PXRD at a value of two theta of 1 1 .9 + 0.1 °. In another embodiment, the present invention describes a lower hydrate with a characteristic maximum value in the PXRD model at a value of two theta of 15.9 + 0.1 °. In another embodiment, the present invention describes a lower hydrate having a characteristic maximum value in the PXRD model at a value of two theta of 16.4 + 0.1 °. In another embodiment, the present invention describes a lower hydrate with a characteristic maximum value in the PXRD model at a two-theta value of 22.4 + 0.1 X. In another embodiment, the present invention describes a lower hydrate with a characteristic maximum value in the PXRD model a a value of two theta of 23.0 + 0.1 °. In another embodiment, the present invention describes a lower hydrate with 1.7% to 6.1% water by weight which has characteristic maximum values in the PXRD model at two theta values of 6.0 + 1.0 °, 8.0_ + 1 -0 °, 11.9 + 1 .0 °, 15.9 + 1 .0 °, 16.4 + 1 .0 °, 22.4 + 1 .0 °, and 23.0 + 1 .0 °. In yet another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a characteristic maximum value in the PXRD model at a value of two theta of 5.5 + 1.0 °. In another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a maximum characteristic value in the PXRD model at a value of two theta of 10.9 + 1 .0 °. In still another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a maximum characteristic value in the PXRD model at a value of two theta of 12.6 + 1 .0 °. In yet another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a characteristic maximum value in the PXRD model at a value of two theta of 14.7 + 1.0 °. In still another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a maximum characteristic value in the PXRD model at a value of two theta of 16.6 + 1 .0 °. In still another embodiment the present invention describes a new crystal form of Cefdinir anhydrate with a maximum characteristic value in the PXRD model at a value of two theta of 21.8 + 1 .0 °. In still another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with a maximum characteristic value in the PXRD model at a value of two theta of 27.3 + 1 .0 °. In yet another embodiment, the present invention describes a new crystal form of Cefdinir anhydrate with characteristic maximum values in the PXRD model at two theta values of 5.5 +. 1. 0 °, 10.9 + 1 .0 °, 12.6 + 1.0 °, 14.7 + 1.0 °, 16.6 + 1.0 °, 21 .8 + 1 .0 °, and 27.3 + 1 .0 °. Another embodiment of the present invention relates to a pharmaceutical composition comprising the Cefdinir trihemihydrate form of the present invention in combination with a pharmaceutically acceptable carrier. In still another embodiment, the present invention relates to a pharmaceutical composition comprising any of the lower hydrate forms of Cefdinir of the present invention in combination with a pharmaceutically acceptable carrier. In another embodiment, the present invention relates to a pharmaceutical composition comprising the Cefdinir anhydrate form of the present invention in combination with a pharmaceutically acceptable carrier. Other embodiments refer to a method for treating bacterial infections by administering any of the pharmaceutical compositions of the present invention.

Detailed Description of the Invention The present invention relates to a form of Cefdinir hydrate, such as trihemihydrate, a form of Cefdinir anhydrate, and isostructural lower hydrate forms of Cefdinir. In general, crystalline organic substances contain different amounts of solvent within their crystalline lattice. As used herein, hydrates are defined as crystalline forms of an organic substance in which the solvent is water. Hydrates and anhydrous crystalline forms are characterized by their X-ray diffraction patterns as measured by PXRD and single-crystal X-ray diffraction. Hydrates can be solvated or desolvated to form other hydrates. Figure 1 is the single crystal X-ray diffraction for the Cefdinir trihemihydrate form. For four molecules of Cefdinir (large structures) there are 14 water molecules within the grid (single points), representing 3.5 moles of water per molecule of Cefdinir). It was unexpectedly found that Cefdinir also exists in several forms of lower hydrate which instead of significant variations in their molar water content maintain the same PXRD model. These lower hydrate forms are also called isomorphic or isostructural hydrates because they retain the order of three dimensions of the original crystal, as defined by the spatial group symmetry and lattice parameters, but have varying amounts of water in the lattice. Figure 3 is the single-crystal X-ray diffraction for one of the lower hydrates isoestructuraies, which shows that for four molecules of Cefdinir (large structures) there are 5 water molecules within the grid (single points), representing 0.8 moles of water per molecule of Cefdinir. PXRD was performed on Cefdinir samples using an XDS-2000 / X-ray diffractometer equipped with a 2 kW normal focus X-ray tube and a Peltier cooled germanium solid state detector (Scintag Inc., Sunnyvale, CA). The information was processed using the DMSNT software (version 1 .37). The X-ray source was a copper filament operated at 45 kV and 40 mA. The alignment of the goniometer was checked daily using an Aluminum Oxide standard. The sample was placed in a thin layer on a zero-bottom plate, and was scanned continuously at a rate of 2 ° two theta per minute over a range of 2 to 40 ° two theta. The maximum value positions of the characteristic PXRD model are reported in terms of the angular positions (two theta) with a permissible variability of + 0.1 °. This allowable variability is specified by the US Pharmacopoeia, pages 1843-1884 (1995). The variability of + 0.1 ° is intended to be used when comparing two powder X-ray diffraction models. In practice, if a maximum value of the diffraction model of a model is assigned a range of angular positions (two theta) which is the position of maximum value measured + 0.1 ° and if those ranges of positions of maximum value are superimposed, then it is considered that the two maximum values have the same annular position (two theta). For example, if a maximum value of the model of diffraction of a model is determined by having a position of maximum value of 5.2 °, for comparison purposes the permissible variability allows the maximum value to be assigned to a position in the range of 5.1 ° -5.3 °. If a maximum comparison value of the other diffraction model is determined to have a maximum value position of 5.3 °, for comparison purposes the allowable variability allows the maximum value to be assigned to a position in the range of 5.2 ° -5.4 °. Because there is an overlap between the two ranges of maximum value positions (ie, 5.1 ° -5.3 ° and 5.2 ° -5.4 °) the two maximum values that are compared are considered to have the same angular position (two theta ). Figures 2, 4 and 5 show the different PXRD models of the trihemihydrate forms, an isostructural lower hydrate, and Cefdinir anhydrate, respectively. As shown in Figure 2, the crystal form of Cefdinir trihemihydrate, which contains 3.5 moles of water for each molecule of Cefdinir (approximately 14% by weight of water) shows the characteristic maximum values in the PXRD model at values of two theta of 5.4 + 0.1 °, 10.7 + 0.1 °, 14.2 + 0.1 °, 15.2 + 0.1 °, 21.4 + 0.1 °, 29.2 + 0.1 °, and 30.6 + 0.1 °. The top line represents the predicted model obtained from single crystal data and the bottom line is the experimental model. Figure 4 shows the lower isostructural hydrate that has characteristic maximum values in the PXRD model at two theta values of 6.0 + 0.1 °, 8.0 + 0.1 °, 11.9 + 0.1 °, 15.9 + 0.1 °, 16.4 + 0.1 °, 22.4 + 0.1 °, and 23.0 + 0.1 °. The upper line represents the predicted model obtained from the single crystal data and the lower line is the experimental model, as for the trihemihydrate, the predicted model equals well with the experimentally obtained model. As discussed above, these isostructural lower hydrates have different water contents, from 1.7% to 6.1% by weight, but maintain similar powder X-ray diffraction patterns. Figure 6 shows the similarity between the PXRD models obtained from two of the lower isostructural hydrates of the present invention, one with approximately 6% water and another with approximately 4% water (1.5 and 0.8 moles of water per molecule of Cefdinir). A new crystal form of Cefdinir anhydrate, which contains zero percentage of water, shows maximum values in the X-ray powder diffraction model at two theta values of 5.5 + 0.1 °, 10.9 + 0.1 °, 12.6 + 0.1 ° ,, 14.7 + 0.1 °, 16.6 + 0.1 °, 21.8 + 0.1 °, and 27.3 + 0.1 ° (Figure 5). The Gravimetric Analysis of Dynamic Sorption / Desorption of Moisture (DMSG hereafter) was performed for the lower isostructural hydrates. A vacuum moisture balance (MB 300G, VTI Corporation) was used to study sorption and moisture desorption. The samples were first dried at 50 ° C under vacuum at a constant weight. The relative humidity was increased to 90% in 10% increments. If the weight of the sample remained unchanged (ie changed by <3 mg / 15 min), the moisture content was recorded. The balance was calibrated before the experiment and the accuracy of the relative humidity measurement was verified with polyvinylpyrrolidone K90. Figure 7 shows the moisture desorption isotherm of the hydrates of the present invention. Acute stages, for example, with relative humidity changes of 40% to 50%, occur when the crystal exceeds the phase change, ie a change in crystal structure. Relatively, the flat regions represent a single phase, that is, where the crystalline structure does not change and is more physically stable. Increases in relative humidity from 10% to almost 40% result in a series of lower hydrate forms of Cefdinir. The new lower hydrate forms, which are the subject of the present invention, varied but maintained the same crystal structure and PXRD models (see Figure 6). An increase in relative humidity of 40% to 50% induced a change in crystal structure, and additional increases in relative humidity of 50% to 90% induced the formation of a more stable phase of the crystal corresponding to a trihemihydrate form of Cefdinir containing about 14% by weight of water. Table 1 summarizes the weight changes of the different forms of Cefdinir hydrate in relation to changes in relative humidity. The changes in weight are expressed by percentage of water content and by the calculated theoretical molar content of water. Table 1 Pharmaceutical Compositions According to the methods of treatment and the pharmaceutical compositions of the invention, the compounds can be administered alone or in combination with other agents. When the compounds are used, the therapeutically effective dose level specific to any particular patient will depend on such factors as the disorder being treated and the severity of the disorder; the activity of the particular compound used; the specific composition employed; age, body weight, general health, sex, and diet of the patient; the time of administration; the route of administration; the rate of excretion of the compound employed; the duration of treatment; and the drugs used in combination with or coincidentally with the compound used. The compounds may be administered orally, parenterally, intranasally, rectally, vaginally, or locally in unit dose formulations containing vehicles, adjuvants, diluents, vehicles, or combinations thereof. The term "parenteral" includes infusion as well as subcutaneous, intravenous, intramuscular and intrrnal injection. The parenterally administered oleaginous or aqueous suspensions of the compounds can be formulated with dispersing, wetting, or suspending agents. The present invention appreciates that the solid forms of the present invention; for example: trihemihydrate and lower isostructural hydrates can be formulated into suspension products. The injectable preparation can also be a suspension or solution for injection in a diluent or solvent. Among the acceptable diluents or solvents employed are water, saline, Ringer's solution, regulators, monoglycerides, diglycerides, fatty acids such as oleic acid, and fixed oils such as monoglycerides or diglycerides. The effect of the parentally administered compounds can be prolonged by decreasing their release rates. One way to decrease the rate of release of a particular compound is to administer injectable depot forms comprising suspensions of sparingly soluble or otherwise insoluble forms of the compound in water. The rate of release of the compound depends on its rate of dissolution, which, in turn, depends on its physical state. Another way to decrease the rate of release of a particular compound is to administer injectable depot forms comprising the compound as an oleaginous solution or suspension. Yet another way to decrease the rate of release of a particular compound is to administer injectable depot forms comprising microcapsule binders of the compound entrapped with liposomes, or biodegradable polymers such as polylactide-polyglycolide, polyorthoesters or polyanhydrides. Depending on the ratio of drug to polymer and the composition of the polymer, the rate of drug release can be controlled. Transdermal patches can also provide controlled delivery of the compounds. The rate of release can be decreased by using membranes that control the release or by trapping the compound within a polymer or gel binder. Conversely, absorption enhancers can be used to increase absorption. Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In these solid dosage forms, the active compound may optionally comprise excipients such as sucrose, lactose, starch, microcrystalline cellulose, mannitol, talc, silica, polyvinylpyrrolidone, sodium starch glycolate, magnesium stearate, etc. Capsules, tablets and pills may also comprise regulating agents, and tablets and pills may be prepared with enteric coatings or other release controlling coatings. Powders and sprays may also contain excipients such as talc, silica, sucrose, lactose, starch, or mixtures thereof. The sprinklers may additionally contain normal propellants such as chlorofluorohydrocarbons or substitutes thereof. Solid dosage forms for oral administration include emulsions, microemulsions, solutions, suspensions, syrups, and elixirs comprising inert diluents such as water. These compositions may also comprise adjuvants such as wetting, emulsifying, suspending, sweetening, flavoring and flavoring agents. The liquid dosage forms may also be contained within soft elastic capsules. Local dosage forms include ointments, pastes, creams, lotions, gels, powders, solutions, sprays, inhalers, and transdermal patches. The compound is mixed, if necessary under sterile conditions, with a vehicle and any of the necessary preservatives or regulators. These dosage forms may also include excipients such as vegetable and animal fats, oils, waxes, paraffins, starch, tragacanth, cellulose derivatives, polyethylene glycols, silicones, bentonites, talc and zinc oxide, or mixtures thereof. Suppositories for rectal or vaginal administration can be prepared by mixing the compounds with a suitable non-irritating excipient such as coconut butter or polyethylene glycol, each of which is solid at ordinary temperature but fluid in the rectum or vagina. Ophthalmic formulations comprising eye drops, eye ointments, powders, and solutions are also contemplated as being within the scope of this invention. Form I of Cefdinir A pure Cefdinir can be obtained by acidifying the solution containing Cefdinir at room temperature or under heating and having crystals separated from the solution in such a way. Suitable examples of the solution containing Cefdinir may include, for example, an aqueous solution of the alkali metal salt of Cefdinir. The solution containing Cefdinir is acidified, if necessary, after said solution is subjected to column chromatography on activated charcoal, non-ionic absorption resin, aluminum, acid aluminum oxide. The acidification process can be carried out by adding an acid such as hydrochloric acid or the like preferain the temperature range from room temperature to 40 ° C, more preferafrom 15 ° to 40 ° C. The amount of the acid to be added preferamakes the pH value of the solution from about 1 to about 4. A pure Cefdinir can also be obtained by dissolving the Cefdinir in an alcohol (preferamethanol), continuing stirring this solution slowly under heating (preferaunder 40 ° C), preferaafter the addition of water was heated to almost the same temperature as that of said solution, then cooling this solution to room temperature and letting it stand. During the crystallization of Cefdinir, it is preferable to keep the amount slightly beyond saturation. Cefdinir obtained according to the aforementioned process can be collected by filtration and dried by means of conventional methods. 7- [2- (2-Aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen-4-carboxylic acid (syn isomer) (29.55 g) can be added to water (300 ml) and the The mixture was adjusted to pH 6.0 with saturated aqueous sodium bicarbonate solution. The resulting solution can be subjected to column chromatography on activated charcoal and eluted with 20%) aqueous acetone. The fractions are combined and concentrated to a volume of 500 ml. The resulting pH solution is adjusted to 1.8 at 35 ° C with 4N hydrochloric acid. The resulting precipitates are collected by filtration, washed with water and dried to give 7- [2- (2-aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen-4-carboxylic acid. (syn isomer). Alternatively, to a solution of 7- [2- (2-aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen-4-carboxylic acid (syn isomer) (0.5 g) in methanol (10 ml) hot water (35 ° C) can be added dropwise; 1.5 ml) at 35 ° C and the resulting solution was stirred slowly for 3 minutes, then left to stand at room temperature. The resulting crystals are collected by filtration, washed with water and then dried to give the acid 7- [2- (2-aminothiazol-4-yl) -2-hydroxyiminoacetamide] -3-vinyl-3-cefen- 4- carboxylic (syn isomer) as crystals. The Cefdinir trihemihydrate form was prepared by suspending Cefdinir, (c.a. 0.8 g) in 1: 1 ethanocylacetase solution (a 5 mL beaker was used). To this suspension, approximately 6 drops of concentrated H2SO with intermittent sonication. The solution first became clear and then a thick yellowish gel formed. A couple of drops of water was added to the gel and the gel was transferred to the funnel and an attempt to wash the gel resulted in the formation of a white suspension. The white suspension was transferred to centrifugal tubes and centrifuged. The two phases separated. The aqueous layer was discarded, more water was added, the vortex was mixed and centrifuged. This procedure was repeated until the pH of the aqueous layer was approximately 3.5. The solid was analyzed like this. Another method for making the trihemihydrate form is to suspend Cefdinir, c. to. 0.8 g in 1: 1 ethanoethylacetate solution (a 5 mL beaker was used). To this suspension, approximately 6 drops of concentrated H2SO with intermittent sonication. The solution first became clear and then a thick yellowish gel formed. To the gel a couple of drops of water was added and the gel was transferred to the centrifuge tubes as follows: To each 14 mL tube, 9 mL of water was added, then enough gel was added to make 12 mL and 2 mL of water added to give 14 mL. Six such tubes were prepared. In each tube the white suspension was formed. The white suspension was centrifuged. The two phases separated. The aqueous layer was discarded, more water was added, the vortex was mixed and centrifuged. This procedure was repeated until the pH of the aqueous layer was about 3.5. The solid was analyzed like this. The lower hydrate forms of Cefdinir were generated by heating the trihemihydrate at 75 ° C for 30 min, or by air drying for 3-24 hours, depending on the sample size. The foregoing is merely illustrative of the invention and is not intended to limit the invention to the embodiments described. The variations and changes, which are obvious to a person skilled in the art, are intended to be within the scope and nature of the invention, which are defined in the appended claims.

Claims (59)

1. CLAIMS 1. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 5.4 + 0.1 °.
2. 2. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at a value of two theta of 1 0.7 + 0.1 °.
3. 3. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 14.2 + 0.1 °.
4. 4. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the X-ray powder diffraction model at two theta value of 15.2 + 0.1 °.
5. 5. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 21.4 + 0.1 °.
6. 6. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 29.2 + 0.1 °.
7. 7. A crystal form of Cefdinir trihemihydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 30.6 + 0.1 °.
8. 8. A crystal form of Cefdinir trihemihydrate with maximum values in the powder X-ray diffraction model at two theta values of 5.4 + 0.1 °, 1 0.7 + 0.1 °, 14.2 + 0.1 °, 1 5.2 +

   0. 1 °, 21.4 + 0.1 °, 29.2 + 0.1 °, and 30.6 + 0.1 °.
9. 9. The crystalline form of claim 8, which contains 3.5 moles of water per molecule of Cefdinir.
10. 10. The crystalline form of claim 8, whose water content is 14% by weight. eleven .
11. A lower hydrate form of Cefdinir with a maximum characteristic value in the powder X-ray diffraction model at a value of two theta of 6.0 + 0.1 °.
12. 12. A Cefdinir lower hydrate form with a characteristic maximum value in the X-ray powder diffraction model at a value of two theta of 8.0 + 0.1 °.
13. 13. A Cefdinir lower hydrate form with a characteristic maximum value in the X-ray powder diffraction model at two theta values of 1 1 .9 + 0.1 °.
14. 14. A lower hydrate form of Cefdinir with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 15.9 + 0.1 °.
15. 15. A form of Cefdinir lower hydrate with a characteristic maximum value in the X-ray powder diffraction model at two theta value of 22.4 + 0.1 °.
16. 16. A form of Cefdinir lower hydrate with a characteristic maximum value in the X-ray powder diffraction model at two theta values of 23.0 + 0.1 °.
17. 17. Cefdinir lower hydrate forms with characteristic maximum values in the powder X-ray diffraction model at two theta values of 6.0 + 0.1 °, 8.0 + 0.1 °, 1 1.9 + 0.1 °, 15.9 + 0.1 °, 16.4 + 0.1 °, 22.4 + 0.1 °, and 23 + 0.1 °.
18. 18. The lower hydrate forms of claim 17, whose water content is 6.1% by weight.
19. 19. The lower hydrate forms of claim 17, whose water content is 6.0% by weight.
20. 20. The lower hydrate forms of claim 17, whose water content is 5.8% by weight.
21. 21. The lower hydrate forms of claim 17, whose water content is 5.7% by weight.
22. 22. The lower hydrate forms of claim 17, whose water content is 5.5% by weight.
23. 23. The lower hydrate forms of claim 17, whose water content is 4.9% by weight.
24. 24. The lower hydrate forms of claim 17, whose water content is 4.4% by weight.
25. 25. The lower hydrate forms of claim 17, whose water content is 3.8% by weight.
26. 26. The lower hydrate forms of claim 17, whose water content is 1.7% by weight.
27. 27. A form of Cefdinir anhydrate with a characteristic maximum value in the X-ray powder diffraction model at value of two theta of 5.5 + 0.1 °.
28. 28. One form of Cefdinir anhydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 10.9 + 0.1 °.
29. 29. One form of Cefdinir anhydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 12.6 + 0.1 °.
30. 30. One form of Cefdinir anhydrate with a characteristic maximum value in the powder X-ray diffraction model at two theta value of 14.7 + 0.1 °.
31. 31 A form of Cefdinir anhydrate with a maximum characteristic value in the powder X-ray diffraction model at two theta value of 16.6 + 0.1 °.
32. 32. One form of Cefdinir anhydrate with a maximum characteristic value in the powder X-ray diffraction model at two-theta value of 21.8 + 0.1 °.
33. 33. One form of Cefdinir anhydrate with a characteristic maximum value in the powder X-ray diffraction model at two theta value of 27.3 + 0.1 °.
34. 34. One form of Cefdinir anhydrate with characteristic maximum values in the powder X-ray diffraction model at two theta values of 5.5 + 0.1 °, 10.9 + 0.1 °, 12.6 + 0.1 °, 14.7 + 0.1 °, 1 6.6 + 0.1 °, 21 .8 + 0.1 °, and 27.3 + 0.1 °.
35. 35. A pharmaceutical composition comprising the trihemihydrate form of claim 8 or 9 in combination with a pharmaceutically acceptable carrier.
36. 36. A pharmaceutical composition comprising any of the lower hydrate crystal forms of claim 17 in combination with a pharmaceutically acceptable carrier.
37. 37. A pharmaceutical composition comprising the lower hydrate crystal form of claim 1 in combination with a pharmaceutically acceptable carrier.
38. 38. A pharmaceutical composition comprising the lower hydrate crystal form of claim 1 in combination with a pharmaceutically acceptable carrier.
39. 39. A pharmaceutical composition comprising the lower hydrate crystal form of claim 20 in combination with a pharmaceutically acceptable carrier.
40. 40. A pharmaceutical composition comprising the lower hydrate crystal form of claim 21 in combination with a pharmaceutically acceptable carrier.
41. 41 A pharmaceutical composition comprising the lower hydrate crystal form of claim 22 in combination with a pharmaceutically acceptable carrier.
42. 42. A pharmaceutical composition comprising the lower hydrate crystal form of claim 23 in combination with a pharmaceutically acceptable carrier.
43. 43. A pharmaceutical composition comprising the lower hydrate crystal form of claim 24 in combination with a pharmaceutically acceptable carrier.
44. 44. A pharmaceutical composition comprising the lower hydrate crystal form of claim 25 in combination with a pharmaceutically acceptable carrier.
45. 45. A pharmaceutical composition comprising the lower hydrate crystal form of claim 26 in combination with a pharmaceutically acceptable carrier.
46. 46. A pharmaceutical composition comprising the anhydrate crystal form of claim 34 in combination with a pharmaceutically acceptable carrier.
47. 47. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 8.
48. 48. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of the claim. 9.
49. 49. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 17.
50. 50. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form. of claim 18.
51. 51. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 1.
52. 52. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of the claim. 20.
53. 53. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 21.
54. 54. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 22.
55. 55. A method of treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of the claim. 23.
56. 56. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 24.
57. 57. A method of treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 25.
58. 58. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising the crystal form of claim 26.
59. 59. A method for treating a bacterial infection by administering a pharmaceutically acceptable composition comprising of the crystal form of claim 37.