(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date 26 November 2009 (26.11.2009) WO 2009/143297 Al (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every AOlN 57/00 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, (21) International Application Number: CA, CH, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, PCT/US2009/044746 EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, (22) International Filing Date: HR, HU, ID, IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, 20 May 2009 (20.05.2009) KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, (25) Filing Language: English NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, (26) Publication Language: English SK, SL, SM, ST, SV, SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (30) Priority Data: 61/054,765 20 May 2008 (20.05.2008) US (84) Designated States (unless otherwise indicated, for every kind of regional protection available): ARIPO (BW, GH, (71) Applicant (for all designated States except US): NEU- GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, ROGESX, INC. [US/US]; 2215 Bridgepointe Parkway, ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, Suite 200, San Mateo, CA 94404 (US). TM), European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, (72) Inventors; and MC, MK, MT, NL, NO, PL, PT, RO, SE, SI, SK, TR), (75) Inventors/Applicants (for US only): MUHAMMAD, OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, GW, ML, Naweed [PK/US]; 5070 Cobb Court, Fremont, CA 94538 MR, NE, SN, TD, TG). (US). BLEY, Keith, R. [US/US]; 227 Ada Avenue, Unit D, Mountain View, CA 94043 (US). Published: (74) Agents: FECHTER, Eric, J . et al; Morrison & Foerster — with international search report (Art. 21(3)) LLP, 755 Page Mill Road, Palo Alto, CA 94304-1018 (US). (54) Title: CARBONATE PRODRUGS AND METHODS OF USING THE SAME Time (minutes post-dose) FIGURE 3 (57) Abstract: The present invention provides carbonate prodrugs which comprise a carbonic phosphoric anhydride prodrug m oi ety attached to the hydroxyl or carboxyl group of a parent drug moiety. The prodrugs may provide improved physicochemical properties over the parent drug. Also provided are methods of treating a disease or condition that is responsive to the parent drug using the carbonate prodrugs, as well as kits and unit dosages. CARBONATEPRODRUGS AND METHODS OF USING THE SAME CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority benefit of United States Provisional Application No. 61/054,765, entitled "Carbonate Prodrugs and Methods of Using The Same" filed May 20, 2008, the content of which is hereby incorporated by reference in its entirety as if it was set forth in full below. BACKGROUND OF THE INVENTION [0001] A drug which exhibits an excellent bioactivity and safety profile when tested in experimental models may be less active and/or more toxic when administered to human subjects. One possible reason for this disparity is that a molecule may be unable to reach target site(s) of action at therapeutic concentrations and/or accumulate at toxic levels in one or more tissues. Such pharmacokinetic differences between in vitro and in vivo models, and between test species and humans, may significantly limit the therapeutic utility of certain compounds, making drug development a challenge. [0002] Physicochemical properties, therapeutically effective dosage, and route of administration, can each influence the pharmacokinetic profile of a drug molecule. The therapeutically effective dosage is fixed for a particular drug. Nonetheless, a change in the route of administration may allow a reduced drug dosage if the new route offers higher bioavailability. For instance, given suitable physicochemical properties, a drug with poor oral bioavailability requiring a high dosage may be formulated for parenteral administration at a lower dosage due to its improved bioavailability. However, a different route of administration is generally possible only if physicochemical properties of a given drug molecule are suitable for the new dosage form. The physicochemical makeup of many existing drugs limits their use to oral administration, resulting in high dosages and poor pharmacokinetic profiles. Accordingly, efforts have been made to modify the physicochemical properties of existing drugs and/or their formulations. [0003] A drug with poor solubility will often exhibit poor bioavailability - a situation which can either hinder the drug development or require administration of high dosages to attain therapeutically effective blood levels of the drug. Tricor® (fenofibrate), for example, was launched as a 300 mg capsule. Particle size reduction to a fine powder increased the solubility of the drug and allowed a dosage reduction down to 200 mg. Addition of a surfactant to the fine powder led to a formulation with a bioavailability similar to the 300 mg and 200 mg dosages using only a 160 mg dosage tablet. Another bioequivalent formulation containing nano-particles of the drug allowed for an effective 145 mg dosage. Thus, a significant decrease in the dosage of Tricor (greater than 100%) was achieved by increasing its solubility which led to an increase in bioavailability. However, despite some examples of solubility improvements from particle size reduction, the intrinsic conditions of oral administration (e.g., limited aqueous media in the GI tract) may limit the solubility and bioavailability enhancements for certain drugs. [0004] Another technique used to increase solubility is to make molecular complexes of insoluble/poorly soluble drugs with more soluble molecules such as cyclodextrins. Itraconazole (Sporanox®), voriconazole (Vfend®) and zisprasidone (Geodon®) are examples of successful applications of this technique. However, this application generally requires a large excess of cyclodextrin relative to the amount of drug being solubilized and may not impart the desired increase in solubility to the entire drug sample (for instance, a dosage of 10 mg itraconazole, 200 mg of voriconazole, or 20 mg of zisprasidone requires 400 mg, 3200 mg, or 294 mg of cyclodextrin, respectively). [0005] While the importance of discovering new drugs cannot be overstated, the ability to improve the physicochemical properties of existing drugs has it bounties. Therefore, there is still a clear and unmet need for improved drugs, such as prodrugs of existing drugs. [0006] The disclosures of all publications, patents, patent applications and other references referred to herein are hereby incorporated herein by reference in their entireties. BRIEF SUMMARY OF THE INVENTION [0007] The present invention relates to prodrugs and methods of their use in therapy. One aspect provides a prodrug comprising (a) a moiety of parent drug, wherein the parent drug comprises a hydroxyl group or a carboxyl group, or both, and (b) a prodrug moiety of the formula -C(O)O-P(O)(OH) 2 wherein the prodrug moiety is bound to the moiety of the parent drug at the hydroxyl group and/or the carboxyl group providing a carbonate moiety, or a pharmaceutically acceptable salt thereof or solvate of the foregoing. In some of these embodiments, the parent drug is not a C1-C alcohol (e.g., not methanol, ethanol, or phenol). In some embodiments, the parent drug is a compound selected from the parent drug compounds of group (I), (II), or (III), as described herein. [0008] In some embodiments, the prodrug is of formula (IV): (IV) or a pharmaceutically acceptable salt thereof or solvate of the foregoing. [0009] In some embodiments, the invention embraces a formulation comprising the prodrug of formula (IV) and a carrier. Also embraced are formulations comprising a carbonate prodrug as described herein of any one of the parent drugs selected from the group (I), (II), or (III) and a carrier. In some embodiments, the formulation comprises an effective amount of the prodrug and a carrier. In some embodiments, the carrier is a pharmaceutically acceptable carrier. In one aspect, the carrier is an aqueous carrier such as saline, which carrier may be at about physiological pH. In some embodiments, the invention embraces a substantially pure form of the prodrug. [0010] In some embodiments, the invention embraces a formulation comprising the compound of formula (IV), or a pharmaceutically acceptable salt thereof or solvate of the foregoing, and an opioid, a non-steroidal anti-inflammatory drug (NSAID), a benzodiazepine and/or a barbiturate. In some embodiments, the invention embraces a formulation comprising the compound of formula (IV), or a pharmaceutically acceptable salt thereof or solvate of the foregoing, and codeine, morphine, hydrocodone, hydromorphone, levorphanol, aspirin, ketorolac, ibuprofen, naproxen, caffeine, tramadol, dextropropoxyphene, methylhexital, diazepam, lorazepam and/or midazolam. [0011] In another aspect, the present invention provides methods of delaying the onset of parent drug action in an individual, comprising administering to the individual an effective amount the prodrug of formula (IV) or a carbonate prodrug as described herein of any one of the parent drugs selected from the group (I), (II), or (III), or a pharmaceutically acceptable salt thereof or solvate of the foregoing, wherein the prodrug provides a slower onset of parent drug action as compared to the parent drug. [0012] In another aspect, the present invention provides methods of prolonging parent drug activity in an individual, comprising administering to the individual an effective amount of the prodrug formula (IV) or a carbonate prodrug as described herein of the parent drug selected from group (I), (II), or (III), or a pharmaceutically acceptable salt thereof or solvate of the foregoing, wherein the prodrug provides prolonged parent drug activity as compared to the parent drug.