(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`CORRECTED VERSION
`
`(19) World Intellectual Property
`Organization
`International Bureau
`
`(43) International Publication Date
`27 January 2005 (27.01.2005) WIPO I PCT
`
`1111111111111111 IIIIII IIIII 11111111111111111111111111111111111 lllll lllll llll 1111111111111111111
`
`(10) International Publication Number
`WO 2005/007081 A9
`
`(51) International Patent Classification:
`A61K 31/19 (2006.01)
`A61K 31/557 (2006.01)
`
`(21) International Application Number:
`
`PCT/US2004/0l640l
`
`(72) Inventors; and
`(75) Inventors/Applicants (for US only): PHARES, Ken
`[US/US]; 194 Amber Wood Run, Chapel Hill, NC 27516
`(US). MOTTOLA, David [US/US]; One Park Drive, Re(cid:173)
`search Triangle Park, NC 27709 (US).
`
`(22) International Filing Date:
`
`(25) Filing Language:
`
`(26) Publication Language:
`
`24 May 2oo4 (24 -05 -2004)
`English
`
`(74) Agents: MAEBIUS, Stephen, B. et al.; FOLEY & LARD-
`NER LLP, Washington Harbour, 3000 K Street N.W.,
`Suite 500, Washington, DC 20007-5143 (US).
`
`English
`
`(81)
`
`(30) Priority Data:
`60/472,407
`
`(71)
`
`22 May 2003 (22.05.2003)
`
`us
`Applicant (for all designated States except US): UNITED
`THERAPEUTICS CORPORATION
`[US/US]; 1735
`Connecticut Avenue, N.W., Third Floor, Washington, D.C.
`20009 (US).
`
`Designated States (unless otherwise indicated, for every
`kind of national protection available): AE, AG, AL, AM,
`AT,AU,AZ,BA,BB,BG,BR,BW,BY,BZ,CA,CH,
`CN, CO, CR, CU, CZ, DE, DK, DM, DZ, EC, EE, EG, ES,
`FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP,
`KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA,
`MD, MG, MK, MN, MW, MX, MZ, NA, NI, NO, NZ,
`OM, PG, PH, PL, PT, RO, RU, SC, SD, SE, SG, SK, SL,
`SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN,
`YU, ZA, ZM, ZW.
`
`[Continued on next page]
`
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`--;;;;;;;;;;;;;; -;;;;;;;;;;;;;; -
`-;;;;;;;;;;;;;;
`;;;;;;;;;;;;;; ----;;;;;;;;;;;;;; -;;;;;;;;;;;;;; -;;;;;;;;;;;;;; --;;;;;;;;;;;;;;
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`;;;;;;;;;;;;;;
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`-;;;;;;;;;;;;;;
`- --------------------------------------------
`
`(54) Title: COMPOUNDS AND METHODS FOR DELIVERY OF PROSTACYCLIN ANALOGS
`
`(57) Abstract: This invention pertains generally to prosta(cid:173)
`cyclin analogs and methods for their use in promoting vas(cid:173)
`odilation, inhibiting platelet aggregation and thrombus form(cid:173)
`ation, stimulating thrombolysis, inhibiting cell proliferation
`(including vascular remodeling), providing cytoprotection,
`preventing atherogenesis and inducing angiogenesis. Gener(cid:173)
`ally, the compounds and methods of the present invention
`increase the oral bioavailability and circulating concentra(cid:173)
`tions of treprostinil when administered orally. Compounds
`of the present invention have formula (I).
`
`(I)
`
`1400
`
`FIGURE IA
`
`'?1000
`
`t r:::800 i 600 •
`
`g
`8 400
`
`-& R118
`-&-R119
`+R120
`
`-e- R121
`--s- R122
`
`Time{min)
`
`FIGURE 1B
`
`-
`
`•
`Time(min)
`
`a
`
`•
`
`-
`
`•
`
`•
`
`Liquidia - Exhibit 1008 - Page 1
`
`

`

`WO 2005/007081 A9 I lllll llllllll 111111111111111111111111111111111111111111111111 lllll lllll llll lllllll 111111111111
`
`(84) Designated States (unless otherwise indicated, for every
`kind of regional protection available): ARIPO (BW, GH,
`GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM,
`ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ,
`TM), European (AT, BE, BG, CH, CY, CZ, DE, DK, EE,
`ES, FI, FR, GB, GR, HU, IE, IT, LU, MC, NL, PL, PT,
`RO, SE, SI, SK, TR), OAPI (BF, BJ, CF, CG, CI, CM,
`GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG).
`
`Published:
`-
`with international search report (Art. 21 (3))
`
`(88) Date of publication of the international search report:
`14 April 2005
`
`(48) Date of publication of this corrected version:
`26 January 201 7
`
`(15) Information about Correction:
`see Notice of26 January 2017
`
`Liquidia - Exhibit 1008 - Page 2
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`COMPOUNDS AND METHODS FOR DELIVERY OF PROSTACYCLIN
`ANALOGS
`
`CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
`
`This application claims benefit of U.S. Provisiortal Application Serial No.
`
`60/472,407, filed on May 22, 2003, the entire contents of which are incorporated by
`
`reference herein.
`
`FIELD OF THE INVENTION
`
`This invention pertains generally to prostacyclin analogs and methods for their
`
`use in promoting vasodilation, inhibiting platelet aggregation and thrombus
`
`formation, stimulating thrombolysis, inhibiting cell proliferation (including vascular
`
`remodeling), providing cytoprotection, preventing atherogenesis and inducing
`
`angiogenesis. Through these prostacyclin-mimetic mechanisms, the compounds of
`
`the present invention may be used in the treatment of/for: pulmonary hypertension,
`
`ischemic diseases (e.g., peripheral vascular disease, Raynaud's phenomenon,
`
`Scleroderma, myocardial ischemia, ischemic stroke, renal insufficiency), heart failure
`
`(including congestive heart failure), conditions requiring anticoagulation (e.g., post
`
`MI, post cardiac surgery), thrombotic microangiopathy, extracorporeal circulation,
`
`central retinal vein occlusion, atherosclerosis, inflammatory diseases ( e.g., COPD,
`
`psoriasis), hypertension (e.g., preeclampsia), reproduction and parturition, cancer or
`
`other conditions of unregulated cell growth, cell/tissue preservation and other
`
`emerging therapeutic areas where prostacyclin treatment appears to have a beneficial
`
`role. These compounds may also demonstrate additive or synergistic benefit in
`
`1
`
`Liquidia - Exhibit 1008 - Page 3
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`combination with other cardiovascular agents ( e.g., calcium channel blockers,
`
`phosphodiesterase inhibitors, endothelial antagonists, antiplatelet agents).
`
`BACKGROUND OF THE INVENTION
`
`Many valuable pharmacologically active compounds cannot be effectively
`
`administered orally for various reasons and are generally administered via intravenous
`
`or intramuscular routes. These routes of administration generally require intervention
`
`by a physician or other health care professional, and can entail considerable
`
`discomfort as well as potential local trauma to the patient.
`
`One example of such a compound is treprostinil, a chemically stable analog of
`
`prostacyclin. Although treprostinil sodium (Remodulin®) is approved by the Food
`
`and Drug Administration (FDA) for subcutaneous administration, treprostinil as the
`
`free acid has an absolute oral bioavailability ofless than 10%. Accordingly, there is
`
`clinical interest in providing treprostinil orally.
`
`Thus, there is a need for a safe and effective method for increasing the
`
`systemic availability oftreprostinil via administration of treprostinil or treprostinil
`
`'
`
`I
`
`analogs.
`
`SUMMARY OF THE INVENTION
`
`In one embodiment, the present invention provides a compound having structure
`
`I:
`
`2
`
`Liquidia - Exhibit 1008 - Page 4
`
`

`

`WO 2005/007081
`
`wherein,
`
`PCT /US2004/016401
`
`R 1 is independently selected from the group consisting ofH, substituted and
`I
`unsubstituted benzyl groups, and groups wherein OR are substituted or unsubstituted
`
`glycolamide esters;
`
`R 2 and R3 may be the same or different and are independently selected from
`the group consisting ofH, phosphate and groups wherein OR2 and OR3 form esters of
`, R2 and R 3 are not H;
`amino acids or proteins, with the proviso that all ofR1
`
`an enantiomer of the compound;
`
`and pharmaceutically acceptable salts of the compound and polymorphs.
`
`In some of these embodiments, R 1 is a substituted or unsubstituted benzyl
`group, such as CH2C6H5. In other embodiments, OR1 is a substituted or unsubstituted
`, R4 and R5 maybe the same or different and
`glycolamide ester, R 1 is -CH2CONR4R 5
`are independently selected from the group consisting ofH, OH, substituted and
`
`unsubstituted alkyl groups, -(CH2)mCH3, -CH2OH, and -CH2(CH2)nOH, with the
`proviso that mis 0, 1, 2, 3 or 4, and n is 0, 1, 2, 3 or 4. In certain of these
`embodiments one or both ofR4 and R 5 are independently selected from the group
`
`consisting ofH, -OH, -CH3, or -CH2CH2OH. In any of the previously discussed
`embodiments, one or both ofR2 and R3 can be H. In some enantiomers of the
`compound R 1=R2=R3=H, or R2=R~=H and R 1=valinyl amide.
`In still further embodiments of the present compounds R2 and R3 are
`independently selected from phosphate and groups wherein OR2 and OR3 are esters of
`amino acids, dipeptides, esters oftripeptides and esters oftetrapeptides. In some
`, compounds only one ofR2 or R 3 is a phosphate group. In other compounds R2 and R3
`are independently selected from groups wherein OR2 and OR3 are esters of amino
`acids, such as esters of glycine or alanine. In any of the above embodiments, one of
`R2 and R3 are H. In certain of the present compounds, the oral bioavailability of the
`compound is greater than the oral bioavailability oftreprostinil, such as at least 50%
`
`or 100% greater than the oral bioavailability oftreprostinil. The above compounds
`
`can further comprise an inhibitor of p-glycoprotein transport. Any of these
`
`compounds can also further comprise a pharmaceutically acceptable excipient.
`
`3
`
`Liquidia - Exhibit 1008 - Page 5
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`The present invention also provides a method of using the above compounds
`
`therapeutically of/for: pulmonary hypertension, ischemic diseases, heart failure,
`
`conditions requiring anticoagulation, thrombotic microangiopathy, extracorporeal
`
`circulation, central retinal vein occlusion, atherosclerosis, inflammatory diseases,
`
`hypertension, reproduction and parturition, cancer or other conditions of unregulated
`
`cell growth, cell/tissue preservation and other emerging therapeutic areas where
`
`prostacyclin treatment appears to have a beneficial role. A preferred embodiment is a
`
`method of treating pulmonary hypertension and/or peripheral vascular disease in a
`
`subject comprising orally administering a pharmaceutically effective amount of a
`
`compound of structure II:
`
`OR3
`,,1111110R2
`
`H
`
`wherein,
`
`RI is independently selected from the group consisting ofH, substituted and
`
`unsubstituted alkyl groups, arylalkyl groups and groups wherein ORI form a
`
`substituted or unsubstituted glycolamide ester;
`
`R2 and R3 may be the same or different and are independently selected from
`the group consisting ofH, phosphate and groups wherein OR2 and OR3 form esters of
`amino acids or proteins, with the proviso that all of RI, R2 and R3 are not H;
`
`an enantiomer of the compound; and
`
`a phannaceutically acceptable salt or polymorph of the compound.
`
`fu some of these methods, when ORI forms a substituted or unsubstituted
`glycolamide ester, RI is -CH2CONR4R5, wherein R 4 and R5 may be the same or
`different and are independently selected from the group consisting ofH, OH,
`
`4
`
`Liquidia - Exhibit 1008 - Page 6
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`substituted and unsubstituted alkyl groups, -(CH2)mCH3, -CH2OH, and -
`CH2(CH2)nOH, with the proviso that mis 0, 1, 2, 3 or 4, and n is 0, 1, 2, 3 or 4. In
`other methods RI is a CI-C4 alkyl group, such as methyl, ethyl, propyl or butyl. In the
`disclosed methods, RI can also be a substituted or unsubstituted benzyl group. In
`other methods, RI can be-CH3 or -CH2C6Hs. In still other methods R4 and R 5 are the
`same or different and are independently selected from the group consisting ofH, OH,
`-CH3, and -CH2CH2OH. In yet other methods, one or both of R2 and R3 are H.
`Altematively, one or both of R2 and R3 are not Hand R2 and R3 are independently
`selected from phosphate and groups wherein OR2 and OR3 are esters of amino acids,
`dipeptides, esters of tripeptides and esters oftetrapeptides. In some methods, only
`one of R2 or R3 is a phosphate group. In additional methods, R2 and R3 are
`independently selected from groups wherein OR2 and OR3 are esters of amino acids,
`such as esters of glycine or alanine. In further methods one of RI and R2 is H. In
`some methods, enantiomers of the compound where RI=R2=R3=H, or R2=R3=H and
`R I=valinyl amide are used.
`
`In various methods the oral bioavailability of the compound is greater than the
`
`oral bioavailability oftreprostinil, such as at least 50% or 100% greater than the oral
`
`bioavailability of treprostinil. The present methods can also comprise administering
`
`pharmaceutically effective amount of a p-glycoprotein inhibitor, simultaneously,
`
`sequentially, or prior to administration of the compound of structure II. In some
`
`embodiments the p-glycoprotein inhibitor is administered orally or intravenously.
`
`The disclosed methods can be used to treat pulmonary hypertension.
`
`The present invention also provides a method of increasing the oral
`
`bioavailability of treprostinil or pharmaceutically acceptable salt thereof, comprising
`
`administering a pharmaceutically effective amount of a p-glycoprotein inhibitor and
`
`orally administering a pharmaceutically effective amount oftreprostinil to a subject.
`
`In certain of these embodiments the p-glycoprotein inhibitor is administered prior to
`
`or simultaneously with the treprostinil. The route of the p-glycoprotein inhibitor
`
`administration can vary, such as orally or intravenously. The present invention also
`
`provides a composition comprising treprostinil or a pharmaceutically acceptable salt
`
`thereof and a p-glycoprotein inhibitor.
`
`5
`
`Liquidia - Exhibit 1008 - Page 7
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`The present compound can also be administered topically or transdermally.
`
`Pharmaceutical formulations according to the present invention are provided
`
`which include any of the compounds described above in combination with a
`
`pharmaceutically acceptable carrier.
`
`The compounds described above can also be used to treat cancer.
`
`Further objects, features and advantages of the invention will be apparent from
`
`the following detailed description.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`Figures lA and lB respectively show plasma concentration versus time curves
`
`for intravenous and intraportal dosing oftreprostinil diethanolamine salt in rats as
`
`described in Example 1;
`
`Figures 2A, 2B and 2C respectively show plasma concentration versus time
`
`curves for intraduodenal, intracolonic and oral dosing of treprostinil di ethanol amine
`
`salt in rats as described in Example 1;
`
`Figure 3 shows on a logarithmic scle the average plasma concentration versus
`
`time curves for the routes of administration described in Example 1;
`
`Figure 4 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following oral administration in rats oftreprostinil methyl
`
`ester as described in Example 2;
`
`Figure 5 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following oral administration in rats oftreprostinil benzyl
`
`ester as described in Example 2;
`
`Figure 6 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following oral administration in rats of treprostinil
`
`diglycine as described in Example 2;
`
`Figure 7 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following oral administration in rates oftreprostinil benzyl
`
`6
`
`Liquidia - Exhibit 1008 - Page 8
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`ester (0:5-mg/kg) and treprostinil diglycine (0.5 mg/kg) as described in Example 2
`
`compared to treprostinil (1 mg/per kg).
`
`Figure 8 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following intraduodenal administration oftreprostinil
`
`monophosphate (ring) as described in Example 3;
`
`Figure 9 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following intraduodenal administration of treprostinil
`
`monovaline (ring) as described in Example 3;
`
`Figure 10 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following intraduodenal administration oftreprostinil
`
`monoalanine (ring) as described in Example 3;
`
`Figure 11 is a graphical representation of the plasma concentration versus time
`
`curve for treprostinil in rat following intraduodenal administration oftreprostinil
`
`monoalanine (chain) as described in Example 3; and
`
`Figure 12 is a graphical representation of the avergage plasma concentration
`
`versus time curve for each prodrug compared to treprostinil alone from Example 1, as
`
`described in Example 3. Treprostinil was dosed at 1 mg/kg whereas the pro drugs were
`
`dosed at 0.5 mg/kg.
`
`Figures 13A - 13D respectively show doses, administered every two hours for
`
`four doses, for either 0.05 mg per dose (total= 0.2 mg), 0.125 mg per dose (total= 0.5
`
`mg), 0.25 mg per dose (total= 1.0 mg), or 0.5 mg per dose (total= 2.0 mg).
`
`Figure 14 shows pharmacokinetic profiles of UT-15 C sustained release tab lets
`
`and sustained release capsules, fasted and fed state.
`
`Figure 15 shows an X ray powder diffraction spectrum of the polymorph Form
`
`A.
`
`Figure 16 shows an IR spechum of the polymorph Form A.
`
`Figure 17 shows a Raman spectrum of the polymorph Form A.
`
`Figure 18 shows thermal data of the polymorph Form A.
`
`7
`
`Liquidia - Exhibit 1008 - Page 9
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`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`Figure 19 shows moisture sorption data of the polymorph Form A.
`
`Figure 20 shows an X ray powder diffraction spectrum of the polymorph Form
`
`B.
`
`Figure 21 shows thermal data of the polymorph Form B.
`
`Figure 22 shows moisture sorption data of the polymorph Form B.
`
`DETAILED DESCRIPTION OF THE INVENTION
`
`Unless otherwise specified, "a" or "an" means "one or more". The present
`
`invention provides compounds and methods for inducing prostacyclin-like effects in a
`
`subject or patient. The compounds provided herein can be formulated into
`
`pharmaceutical formulations and medicaments that are useful in the methods of the
`
`invention. The invention also provides for the use of the compounds in preparing
`
`medicaments and pharmaceutical fonnulations and for use of the compounds in
`
`treating biological conditions related to insufficient prostacyclin activity as outlined in
`
`the Field of Invention. The present invention also provides compounds and methods
`
`for the treatment of cancer and cancer related disorders.
`
`In some embodiments, the present compounds are chemical derivatives of ( + )(cid:173)
`treprostinil, which has the following structure:
`
`OH
`.. ,11111 OH
`
`H
`
`Treprostinil is a chemically stable analog of prostacyclin, and as such is a
`
`potent vasodilator and inhibitor of platelet aggregation. The sodium salt of
`
`treprostinil, (lR,2R,3aS,9aS)-[[2,3,3a,4,9,9a -Hexahydro-2-hydroxy -l-[(3S)-3-
`
`hydroxyoctyl]-lH-benz[f]inden-5-yl] oxy]acetic acid monosodium salt, is sold as a
`
`8
`
`Liquidia - Exhibit 1008 - Page 10
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`solution for injection as Remodulin® which has been approved by the Food and Drug
`
`Administration (FDA) for treatment of pulmonary hypertension. In some
`
`embodiments, the present compounds are derivatives of (-)-treprostinil, the
`enantiomer of ( + )-treprostinil. A preferred embodiment of the present invention is the
`diethanolamine salt of treprostinil. The present invention further includes polymorphs
`
`of the above compounds, with two forms, A and B, being desc1ibed in the examples
`
`below. Of the two fonns, B is preferred. A particularly preferred embodiment of the
`
`present invention is form B of treprostinil diethanolamine.
`
`In some embodiments, the present compounds are generally classified as
`
`prodrugs of treprostinil that convert to treprostinil after administration to a patient,
`
`such as through ingestion. In some embodiments, the prodrugs have little or no
`
`activity themselves and only show activity after being converted to treprostinil. In
`
`some embodiments, the present compounds were produced by chemically derivatizing
`
`treprostinil to make stable esters, and in some instances, the compounds were
`
`derivatized from the hydroxyl groups. Compounds of the present invention can also
`
`be provided by modifying the compounds found in U.S. Patent Nos. 4,306,075 and
`
`5,153,222 in like manner.
`
`In one embodiment, the present invention provides compounds of structure I:
`
`wherein,
`
`R 1 is independently selected from the group consisting ofH, substituted and
`unsubstituted benzyl groups and groups wherein OR 1 are substituted or unsubstituted
`
`glycolamide esters;
`
`9
`
`Liquidia - Exhibit 1008 - Page 11
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`R2 and R3 may be the same or different and are independently selected from
`the group consisting ofH, phosphate and groups wherein OR2 and OR3 form esters of
`
`amino acids or proteins, with the proviso that all ofR1, R2 and R3 are not H;
`
`enantiomers of the compound; and
`
`pharmaceutically acceptable salts of the compound.
`
`In some embodiments wherein OR 1 are substituted or unsubstituted
`glycolamide esters, R 1 is -CH2CONR4Rs and R4 and Rs may be the same or different
`and are independently selected from the group consisting ofH, OH, substituted and
`
`unsubstituted alkyl groups, -(CH2)mCH3, -CH2OH, and -CH2(CH2)nOH, with the
`
`proviso that mis 0, 1, 2, 3 or 4, and n is 0, 1, 2, 3 or 4.
`
`One skilled in the art will also readily recognize that where members are
`
`grouped together in a common manner, such as in a Markush group or the groups
`
`described in the R of structures I and II above and below,' the present invention
`
`encompasses not only the entire group listed as a whole, but each member of the
`
`group individually and all possible subgroups of the main group. Accordingly, for all
`
`purposes, the present invention encompasses not only the main group, but also the
`
`main group.absent one or more of the group members. The present invention also
`
`envisages the explicit exclusion of one or more of any of the group members in the
`claimed invention. For example, R 1 can specifically exclude H, substituted and
`unsubstituted benzyl groups, or groups wherein OR1 are substituted. or unsubstituted
`glycolamide esters.
`In some embodiments, R 1 is a substituted or unsubstituted benzyl groups, such
`as -CH2C6Hs, -CH2C6H4NO2, -CH2C6H4OCH3, -CH2C6H4Cl, -CH2C6H4(NO2)2, or -
`
`CH2C6H4F. The benzyl group can be ortho, meta, para, ortho/para substituted and
`
`combinations thereof. Suitable substituents on the aromatic ring include halogens
`(fluorine, chlorine, bromine, iodine), -NO2 groups, -OR16 groups wherein R16 is Hor
`a C1-C4 alkyl group, and combinations thereof.
`Alternatively, when R 1 is -CH2CONR4R5 then R4 and Rs may be the same or different
`and are independently selected from the group consisting ofH, OH, -CH3, and -
`
`10
`
`Liquidia - Exhibit 1008 - Page 12
`
`

`

`WO 2005/007081
`
`PCT/US2004/016401
`
`,
`
`CH2CH20H. In these compounds where R 1 is not H, generally one or both ofR2 and
`R3 areH.
`In some embodiment one or both ofR2 and R 3 are Hand R 1 is -CH2CONR4R5
`and one or both of R4 and R5 are H, -OH, -CH3, -CH2CH20H.
`In compounds where one or both of R2 and R3 are not H, R2 and R3 can be
`independently selected from phosphate and groups wherein OR2 and OR3 are esters of
`amino acids, dipeptides, esters oftripeptides and esters oftetrapeptides. In some
`embodiments, only one ofR2 or R3 is a phosphate group. In compounds where at
`least one ofR2 and R3 is not H, generally R 1 is H. In additional embodiments, one of
`R2 and R3 are H and thus the compound of structure I is derivatized at only one of R2
`and R3. In particular compounds, R2 is Hand R3 is defined as above. In additional
`embodiments, R 1 and R3 are Hand R2 is a group wherein OR2 is an ester of an amino
`acid or a dipeptide. In further embodiments, R 1 and R2 are Hand R3 is a group
`wherein OR3 is an ester of an amino acid or a dipeptide.
`When one or both of the OR2 and OR3 groups form esters of amino acids or
`peptides, i.e., dipeptides, tripeptides or tetrapeptides, tl;iese can be depicted generically
`as -COCHR6NR7R8 wherein R6 is selected from the group consisting of amino acid
`side chains, R7 and R8 maybe the same or different and are independently selected
`from the group consisting ofH, and-COCHR9NR10R 11
`
`. Generally, reference to
`
`amino acids or peptides refers to the naturally occurring, or L-isomer, of the amino
`
`acids or peptides. However, the present compounds and methods are not limited
`
`thereto and D-isomer amino acid residues can take the place of some or all of L(cid:173)
`
`amina acids. In like mariner, mixtures ofD- and L-isomers can also be used. In the
`embodiments wherein the amino acid is praline, R7 together with R6 forms a
`pyrrolidine ring structure. R 6 can be any of the naturally occurring amino acid side
`chains, for example -CH3 (alanine), -(CH2)3NHCNH2NH (arginine), -CH2CONH2
`(asparagine), -CH2COOH (aspartic acid,), -CH2SH (cysteine), -(CH2)2CONH2
`(glutamine), -(CH2)2COOH (glutamic acid), -H (glycine), -CHCH3CH2CH3
`(isoleucine), -CH2CH(CH3)2 (leucine), -(CH2)4NH2 (lysine), -(CH2)2SCH3
`
`(methionine), -CH2Ph (phenylalanine), -CH20H (serine), -CHOHCH3 (threonine), -
`CH(CH3)2 (valine),
`
`11
`
`Liquidia - Exhibit 1008 - Page 13
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`

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`WO 2005/007081
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`- c~ J (histidine),
`
`H2 ~NH
`
`N
`
`H
`N
`
`(tryptophan), and
`
`OH
`
`(tyrosme),
`
`-(CH2) 3NHCONH2 (citmlline) or-(CH2) 3NH2 (ornithine). Ph designates a phenyl
`
`group.
`
`In the above compounds, R7 and R8 may be the same or different and are
`selected from the group consisting of H, and -COCHR9NR10R 11
`, wherein R 9 is a side
`chain of amino acid, R 10 and R11 maybe the same or different and are selected from
`, wherein R12 is an amino acid side
`the group consisting ofH, and-COCHR12NR13R14
`chain, R 13 and R 14 may be the same or different and are independently selected from
`the group consisting of H, and -COCHR 15NH2. One skilled in the art will realize that
`the peptide chains can be extended on the following scheme to the desired length and
`
`include the desired amino acid residues.
`
`In the embodiments where either or both of OR2 and OR3 groups form an ester
`
`of a peptide, such as dipeptide, tripeptide, tetrapeptide, etc. the peptides can be either
`
`homopeptides, i.e., repeats of the same amino acid, such as arginyl-arginine, or
`
`heteropeptides, i.e., made up of different combinations of amino acids. Examples of
`
`heterodipeptides include alanyl-glutamine, glycyl-glutamine, lysyl-arginine, etc.
`
`As will be understood by the skilled artisan when only one R7 and R 8 includes
`
`a peptide bond to further amino acid, such as in the di, tri and tetrapeptides, the
`resulting peptide chain will be linear. When both R 7 and R 8 include a peptide bond,
`
`then the peptide can be branched.
`
`12
`
`Liquidia - Exhibit 1008 - Page 14
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`

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`WO 2005/007081
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`PCT/US2004/016401
`
`In still other embodiments of the present compounds R1 is Hand one ofR2 or
`R3 is a phosphate group or H while the other R2 or R3 is a group such the OR2 or OR3
`
`is an ester of an amino acid, such as an ester of glycine or alanine.
`
`Pharmaceutically acceptable salts of these compounds as well as
`
`pharmaceutical formulation of these compounds are also provided.
`
`Generally, the compounds described herein have enhanced oral bioavailability
`
`compared to the oral bioavailability of treprostinil, either in free acid or salt fonn.
`
`The described compounds can have oral bioavailability that is at least 25%, 50%
`
`100%, 200%, 400% or more compared to the oral bioavailability of treprostinil. The
`
`absolute oral bioavailability of these compounds can range betwee.n 10%, 15%, 20%,
`
`25%, 30% and 40%, 45%, 50%, 55%, 60% or more when administered orally. For
`
`comparison, the absolute oral bioavailability of treprostinil is on the order of 10%,
`
`although treprostinil sodium has an absolute bioavailability approximating 100%
`
`when administered by subcutaneous infusion.
`
`As will be understood by one skilled in the art, for any and all purposes,
`
`particularly in terms of providing a written description, all ranges disclosed herein,
`
`and in particular the bioavailability ranges described herein also encompass any and
`
`all possible subranges and combinations of subranges thereof. As only one example,
`
`a range of20% to 40%, can be broken down into ranges of20% to 32.5% and 32.5%
`
`to 40%, 20% to 27.5% and 27.5% to 40%, etc. Any listed range can be easily
`
`recognized as sufficiently describing and enabling the same range being broken down
`
`into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting
`
`example, each range discussed herein can be readily broken down into a lower third,
`
`middle third and upper third, etc. As will also be understood by one skilled in the art
`
`all language such as "up to," "at least," "greater than," "less than," "more than" and
`
`the like include the number recited and refer to ranges which can be subsequently
`
`broken down into subranges as discussed above. In the same manner, all ratios
`
`disclosed herein also include all subratios falling within the broader ratio.
`
`Administration of these compounds can be by any route by which the
`
`compound will be bioavailable in effective amounts including oral and parenteral
`
`13
`
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`WO 2005/007081
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`PCT/US2004/016401
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`routes. The compounds can be administered intravenously, topically, subcutaneously,
`
`intranasally, rectally, intramuscularly, transdermally or by other parenteral routes.
`
`When administered orally, the compounds can be administered in any convenient
`
`dosage form including, for example, capsule, tablet, liquid, suspension, and the like.
`
`Testing has shown that that treprostinil can be irritating upon skin contact. fu
`
`contrast, some of the compounds disclosed herein, generally as prodrugs of
`
`treprostinil, are not irritating to the skin. Accordingly, the present compounds are
`
`well suited for topical or transdermal administration.
`
`When administered to a subject, the above compounds, and in particular the
`
`compounds of structure I, are prostacyclin-mimetic and are useful in treating
`
`conditions or disorders where vasodilation and/or inhibition of platelet aggregation or
`
`other disorders where prostacyclin has shown benefit, such as in treating pulmonary
`
`hypertension. Accordingly, the present invention provides methods for inducing
`
`prostacyclin-like effects in a subject comprising administering a pharmaceutically
`
`effective amount of one or more of the compounds described herein, such as those of
`
`structure I above, preferably orally, to a patient in need of such treatment. As an
`
`example, the vasodilating effects of the present compounds can be used to treat
`
`pulmonary hypertension, which result from various forms of connective tissue
`
`disease, such as lupus, sclerodenna or mixed connective tissue disease. These
`
`compounds are thus useful for the treatment of pulmonary hypertension.
`
`fu another embodiment, the present invention also provides methods of
`
`promoting prostacyclin-like effect in a subject by administering a pharmaceutically
`
`effective amount of a compound of structure II:
`
`14
`
`Liquidia - Exhibit 1008 - Page 16
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`WO 2005/007081
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`wherein,
`R1 is independently selected from the group consisting ofH, substituted and
`unsubstituted alkyl groups, arylalkyl groups and groups wherein OR1 form a
`substituted or unsubstituted glycolamide ester;
`R2 and R3 may be the same or different and are independently selected from
`the group consisting ofH, phosphate and groups wherein OR2 and OR3 form esters of
`amino acids or proteins, with the proviso that all of R 1, R2 and R3 are not H;
`
`an enantiomer of the compound; and
`
`a pharmaceutically acceptable salt of the compound.
`
`In groups wherein OR1 form a substituted or unsubstituted glypolamide ester,
`R1 can be -CH2CONR4R5
`, wherein R4 and R5 may be the same or different and are
`independently selected from the group consisting ofH, OH, substituted and
`
`unsubstituted alkyl groups, -(CH2)mCH3, -CH2OH, and -CH2(CH2)11OH, with the
`
`proviso that mis 0, 1, 2, 3 or 4, and n is 0, 1, 2, 3 or 4.
`
`In other methods of inducing vasodilation or treating hypertension, R 1 can be a
`C1-C4 alkyl group, such as methyl, ethyl, propyl or butyl. In other methods R 1 is a
`substituted or unsubstituted benzyl groups, such as -CH2C6H5, -CH2C6H4NO2, -
`CH2C6H4OCH3, -CH2C6H4Cl, -CH2C6H4(NO2)2, or -CH2C6H4F. The benzyl group
`
`can be ortho, meta, para, ortho/para substituted and combinations thereof. Suitable
`
`substituents on the aromatic ring include halogens (fluorine, chlorine, bromine,
`iodine), -NO2 groups, -OR16 groups wherein R16 is Hor a C1-C