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Carreras CW, Fontaine SD, Reid RR, Ashley GW, Santi DV. Long-Acting Poly(ADP-ribose) Polymerase Inhibitor Prodrug for Humans. Bioconjug Chem 2024; 35:551-558. [PMID: 38591781 DOI: 10.1021/acs.bioconjchem.4c00112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Poly(ADP-ribose) polymerase inhibitors (PARPi) have been approved for once or twice daily oral use in the treatment of cancers with BRCA defects. However, for some patients, oral administration of PARPi may be impractical or intolerable, and a long-acting injectable formulation is desirable. We recently developed a long-acting PEGylated PARPi prodrug, PEG∼talazoparib (TLZ), which suppressed the growth of PARPi-sensitive tumors in mice for very long periods. However, the release rate of TLZ from the conjugate was too fast to be optimal in humans. We prepared several new PEG∼TLZ prodrugs having longer half-lives of drug release and accurately measured their pharmacokinetics in the rat. Using the rates of release of TLZ from these prodrugs and the known pharmacokinetics of free TLZ in humans, we simulated the pharmacokinetics of the macromolecular prodrugs and released TLZ in humans. From several possibilities, we chose two conjugates that could be administered intravenously every 2 weeks and maintain TLZ within its known therapeutic window. We describe situations where the PEG∼TLZ conjugates would find utility in humans and suggest how the intravenously administered long-acting prodrugs could in fact be more effective than daily oral administration of free TLZ.
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Affiliation(s)
| | - Shaun D Fontaine
- ProLynx, Inc., 135 Mississippi Street, San Francisco, California 94107, United States
| | - Ralph R Reid
- ProLynx, Inc., 135 Mississippi Street, San Francisco, California 94107, United States
| | - Gary W Ashley
- ProLynx, Inc., 135 Mississippi Street, San Francisco, California 94107, United States
| | - Daniel V Santi
- ProLynx, Inc., 135 Mississippi Street, San Francisco, California 94107, United States
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Fontaine SD, Carreras CW, Reid RR, Ashley GW, Santi DV. A Very Long-acting Exatecan and Its Synergism with DNA Damage Response Inhibitors. Cancer Res Commun 2023; 3:908-916. [PMID: 37377899 PMCID: PMC10208276 DOI: 10.1158/2767-9764.crc-22-0517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/03/2023] [Accepted: 04/18/2023] [Indexed: 06/29/2023]
Abstract
Exatecan (Exa) is a very potent inhibitor of topoisomerase I and anticancer agent. It has been intensively studied as a single agent, a large macromolecular conjugate and as the payload component of antigen-dependent antibody-drug conjugates. The current work describes an antigen-independent conjugate of Exa with polyethylene glycol (PEG) that slowly releases free Exa. Exa was conjugated to a 4-arm 40 kDa PEG through a β-eliminative cleavable linker. Pharmacokinetic studies in mice showed that the conjugate has an apparent circulating half-life of 12 hours, which reflects a composite of both the rate of renal elimination (half-life ∼18 hours) and release of Exa (half-life ∼40 hours). Remarkably, a single low dose of 10 μmol/kg PEG-Exa-only approximately 0.2 μmol/mouse-caused complete suppression of tumor growth of BRCA1-deficient MX-1 xenografts lasting over 40 days. A single low dose of 2.5 μmol/kg PEG-Exa administered with low but efficacious doses of the PARP inhibitor talazoparib showed strong synergy and caused significant tumor regression. Furthermore, the same low, single dose of PEG-Exa administered with the ATR inhibitor VX970 at doses of the DNA damage response inhibitor that do not affect tumor growth show high tumor regression, strong synergy, and synthetic lethality. Significance A circulating conjugate that slowly releases Exa is described. It is efficacious after a single dose and synergistic with ATR and PARP inhibitors.
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Meher N, Ashley GW, Bidkar AP, Dhrona S, Fong C, Fontaine SD, Beckford Vera DR, Wilson DM, Seo Y, Santi DV, VanBrocklin HF, Flavell RR. Prostate-Specific Membrane Antigen Targeted Deep Tumor Penetration of Polymer Nanocarriers. ACS Appl Mater Interfaces 2022; 14:50569-50582. [PMID: 36318757 PMCID: PMC9673064 DOI: 10.1021/acsami.2c15095] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 10/24/2022] [Indexed: 05/05/2023]
Abstract
Tumoral uptake of large-size nanoparticles is mediated by the enhanced permeability and retention (EPR) effect, with variable accumulation and heterogenous tumor tissue penetration depending on the tumor phenotype. The performance of nanocarriers via specific targeting has the potential to improve imaging contrast and therapeutic efficacy in vivo with increased deep tissue penetration. To address this hypothesis, we designed and synthesized prostate cancer-targeting starPEG nanocarriers (40 kDa, 15 nm), [89Zr]PEG-(DFB)3(ACUPA)1 and [89Zr]PEG-(DFB)1(ACUPA)3, with one or three prostate-specific membrane antigen (PSMA)-targeting ACUPA ligands. The in vitro PSMA binding affinity and in vivo pharmacokinetics of the targeted nanocarriers were compared with a nontargeted starPEG, [89Zr]PEG-(DFB)4, in PSMA+ PC3-Pip and PSMA- PC3-Flu cells, and xenografts. Increasing the number of ACUPA ligands improved the in vitro binding affinity of PEG-derived polymers to PC3-Pip cells. While both PSMA-targeted nanocarriers significantly improved tissue penetration in PC3-Pip tumors, the multivalent [89Zr]PEG-(DFB)1(ACUPA)3 showed a remarkably higher PC3-Pip/blood ratio and background clearance. In contrast, the nontargeted [89Zr]PEG-(DFB)4 showed low EPR-mediated accumulation with poor tumor tissue penetration. Overall, ACUPA conjugated targeted starPEGs significantly improve tumor retention with deep tumor tissue penetration in low EPR PC3-Pip xenografts. These data suggest that PSMA targeting with multivalent ACUPA ligands may be a generally applicable strategy to increase nanocarrier delivery to prostate cancer. These targeted multivalent nanocarriers with high tumor binding and low healthy tissue retention could be employed in imaging and therapeutic applications.
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Affiliation(s)
- Niranjan Meher
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
| | - Gary W. Ashley
- ProLynx
Inc., San Francisco, California 94158, United States
| | - Anil P. Bidkar
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
| | - Suchi Dhrona
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
| | - Cyril Fong
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
| | | | - Denis R. Beckford Vera
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
| | - David M. Wilson
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
- Helen
Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California 94143-0981, United States
| | - Youngho Seo
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
- Helen
Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California 94143-0981, United States
| | - Daniel V. Santi
- ProLynx
Inc., San Francisco, California 94158, United States
| | - Henry F. VanBrocklin
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
- Helen
Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California 94143-0981, United States
| | - Robert R. Flavell
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, California 94143, United States
- Helen
Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California 94143-0981, United States
- Department
of Pharmaceutical Chemistry, University
of California, San Francisco, California 94158-2517, United States
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Thomas A, Fontaine SD, Diolaiti ME, Desai P, Kumar R, Takahashi N, Sciuto L, Nichols S, Ashworth A, Feng FY, Ashley GW, Nguyen M, Pommier Y, Santi DV. PLX038: A Long-Acting Topoisomerase I Inhibitor With Robust Antitumor Activity in ATM-Deficient Tumors and Potent Synergy With PARP Inhibitors. Mol Cancer Ther 2022; 21:1722-1728. [PMID: 35999657 PMCID: PMC10673686 DOI: 10.1158/1535-7163.mct-22-0217] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/02/2022] [Accepted: 08/15/2022] [Indexed: 11/16/2022]
Abstract
Alterations in the ATM gene are among the most common somatic and hereditary cancer mutations, and ATM-deficient tumors are hypersensitive to DNA-damaging agents. A synthetic lethal combination of DNA-damaging agents and DNA repair inhibitors could have widespread utility in ATM-deficient cancers. However, overlapping normal tissue toxicities from these drug classes have precluded their clinical translation. We investigated PLX038, a releasable polyethylene glycol-conjugate of the topoisomerase I inhibitor SN-38, in ATM wild-type and null isogenic xenografts and in a BRCA1-deficient xenograft. PLX038 monotherapy and combination with PARP inhibition potently inhibited the growth of both BRCA1- and ATM-deficient tumors. A patient with an ATM-mutated breast cancer treated with PLX038 and the PARP inhibitor rucaparib achieved rapid, symptomatic, and radiographic complete response lasting 12 months. Single-agent PLX038 or PLX038 in combination with DNA damage response inhibitors are novel therapeutic paradigms for patients with ATM-loss cancers.
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Affiliation(s)
| | | | - Morgan E. Diolaiti
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | | | | | | | | | | | - Alan Ashworth
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Felix Y. Feng
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
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Hearn BR, Fontaine SD, Schneider EL, Kraemer Y, Ashley GW, Santi DV. Attenuation of the Reaction of Michael Acceptors with Biologically Important Nucleophiles. Bioconjug Chem 2021; 32:794-800. [PMID: 33822591 DOI: 10.1021/acs.bioconjchem.1c00075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
β-Elimination of drugs tethered to macromolecular carbamates provides a platform for drug half-life extension. However, the macromolecular Michael acceptor products formed upon drug release can potentially react with biological amines and thiols and may raise concerns about safety. We desired to mitigate this possibility by developing linkers that have predictable rates of β-elimination but suppressed rates of nucleophilic addition to their Michael acceptor products. We prepared Michael acceptor products of β-eliminative linkers that contained a methyl group at the Cβ carbon or a gem-dimethyl group at the Cγ carbon and studied the kinetics of their reactions with the most prevalent biological nucleophiles-amine and thiol groups. Aza-Michael reactions with glycine are slowed about 20-fold by methylation of the β-carbon and 175-fold with a gem-dimethyl group at the γ-carbon. Likewise, addition of the glutathione thiol to γ-gem-dimethyl Michael acceptors was retarded 7-24-fold compared to parent unsubstituted linkers. It was estimated that in an in vivo environment of ∼0.5 mM macromolecular thiols or ∼20 mM macromolecular amines-as in plasma-the reaction half-life of a typical Michael acceptor with a γ-gem-dimethyl linker could exceed 3 years for thiols or 25 years for amines. We also prepared a large series of γ-gem-dimethyl β-eliminative linkers and showed excellent structure-activity relationships of elimination rates with corresponding unsubstituted parent linkers. Finally, we compared the first-generation unsubstituted and new gem-dimethyl β-eliminative linkers in a once-monthly drug delivery system of a 39 amino acid peptide. Both linkers provided the desired half-life extension of the peptide, but the Michael acceptor formed from the gem-dimethyl linker was much less reactive. We conclude that the γ-gem-dimethyl β-eliminative linkers provide high flexibility and greatly reduce potential reactions of Michael acceptor products with biologically important nucleophiles.
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Affiliation(s)
- Brian R Hearn
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
| | - Shaun D Fontaine
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
| | - Eric L Schneider
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
| | - Yannick Kraemer
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
| | - Gary W Ashley
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
| | - Daniel V Santi
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, California 94158, United States
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Fontaine SD, Ashley GW, Houghton PJ, Kurmasheva RT, Diolaiti M, Ashworth A, Peer CJ, Nguyen R, Figg WD, Beckford-Vera DR, Santi DV. A Very Long-Acting PARP Inhibitor Suppresses Cancer Cell Growth in DNA Repair-Deficient Tumor Models. Cancer Res 2020; 81:1076-1086. [PMID: 33323380 DOI: 10.1158/0008-5472.can-20-1741] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/21/2020] [Accepted: 12/10/2020] [Indexed: 11/16/2022]
Abstract
PARP inhibitors are approved for treatment of cancers with BRCA1 or BRCA2 defects. In this study, we prepared and characterized a very long-acting PARP inhibitor. Synthesis of a macromolecular prodrug of talazoparib (TLZ) was achieved by covalent conjugation to a PEG40kDa carrier via a β-eliminative releasable linker. A single injection of the PEG∼TLZ conjugate was as effective as ∼30 daily oral doses of TLZ in growth suppression of homologous recombination-defective tumors in mouse xenografts. These included the KT-10 Wilms' tumor with a PALB2 mutation, the BRCA1-deficient MX-1 triple-negative breast cancer, and the BRCA2-deficient DLD-1 colon cancer; the prodrug did not inhibit an isogenic DLD-1 tumor with wild-type BRCA2. Although the half-life of PEG∼TLZ and released TLZ in the mouse was only ∼1 day, the exposure of released TLZ from a single safe, effective dose of the prodrug exceeded that of oral TLZ given daily over one month. μPET/CT imaging showed high uptake and prolonged retention of an 89Zr-labeled surrogate of PEG∼TLZ in the MX-1 BRCA1-deficient tumor. These data suggest that the long-lasting antitumor effect of the prodrug is due to a combination of its long t 1/2, the high exposure of TLZ released from the prodrug, increased tumor sensitivity upon continued exposure, and tumor accumulation. Using pharmacokinetic parameters of TLZ in humans, we designed a long-acting PEG∼TLZ for humans that may be superior in efficacy to daily oral TLZ and would be useful for treatment of PARP inhibitor-sensitive cancers in which oral medications are not tolerated. SIGNIFICANCE: These findings demonstrate that a single injection of a long-acting prodrug of the PARP inhibitor talazoparib in murine xenografts provides tumor suppression equivalent to a month of daily dosing of talazoparib.
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Affiliation(s)
| | | | - Peter J Houghton
- Greehey Children's Cancer Research Institute, UT Health San Antonio, Texas
| | | | - Morgan Diolaiti
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Alan Ashworth
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Cody J Peer
- Pharmacology Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Ryan Nguyen
- Pharmacology Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - William D Figg
- Pharmacology Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Denis R Beckford-Vera
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California
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Fontaine SD, Ashley GW, Houghton PJ, Kurmasheva R, Diolati M, Ashworth A, Santi DV. Abstract LB-060: A very long-acting poly(ADP-ribose) polymerase inhibitor. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-lb-060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: The purpose of this work was to prepare and characterize the anti-tumor properties of a prodrug for a very long-acting of poly(ADP-ribose) polymerase (PARP) inhibitor. Background: Four PARP inhibitors (PARPi) have been approved for QD oral use in treatment of human cancers. It is believed that PARP requires continuous inhibition for optimal anti-tumor effects, but, as with any drug with a short t1/2, daily administered PARPi exhibit high Cmax values and peak-to-trough excursions. We speculated that the prolonged exposure and lower Cmax and Cmax/Cmin of a long-acting PARPi might provide a more effective, less toxic therapeutic. In choosing which PARPi to target, a major consideration was whether the carrier has capacity to deliver sufficient levels of the drug over a long dosing interval. Talazoparib (TLZ) was chosen for this study because it is the most potent of the PARP inhibitors, requiring only 1 mg/day in adults compared to hundreds of mg/day for other PARPi's. Experimental procedures: We prepared a long-acting prodrug of TLZ by attaching it to a PEG40kDa carrier by a β-eliminative releasable linker. The chemistry was achieved by a novel alkylation of TLZ at the poorly acidic 2-NH of the phthalazinone moiety with an O-azidoalkyl-N-alkyl-N-chloromethyl carbamate, followed by coupling to PEG-cyclooctyne. Daily PO doses of TLZ or a single IP injection of the PEG-TLZ conjugate were administered to xenografts in mice possessing defects in homologous recombination - either a PALB2 mutation in the KT-10 Wilms tumor, or a BRCA1-deficient MX-1 triple-negative breast cancer. New data: PEG~TLZ was highly effective in treating both KT-10 and MX-1 xenografts. Although the t1/2 of TLZ in the mouse is only ~3 hr, tumor growth in animals treated with PEG~TLZ was suppressed for about one month. The EFS T/C values - the ratio of the median time to event between treated and control groups - of single injections of ~5 mg TLZ/kg as PEG~TLZ in either tumor was more than 4, indicating the drug is a highly active agent at low doses. The amount of TLZ in a single efficacious dose of the PEG~TLZ conjugate was equivalent to the same amount of free TLZ administered in divided daily doses for 4 or more weeks. Although we did not investigate scheduling, dosing PEG~TLZ once every 3 to 4 weeks should be sufficient to suppress tumor growth for extended periods. Conclusion: We developed a novel method of conjugating linkers to the 2N of the phthalazinone moiety of PARPi. We prepared a cleavable PEG~TLZ that releases TLZ with a t1/2 of 160 hr at pH 7.4. In mouse xenografts of tumors with defective HR, single non-toxic doses of PEG~TLZ suppresses tumor growth for ~1 month, and are equi-effective to QD administration of TLZ over that period. We posit that the long lasting effect is due to the long t1/2 of the prodrug, increased sensitivity of the tumor upon continued exposure to TLZ, tumor accumulation of the 15 nm nanomolecule, and counteracting drug resistance by efflux pumps.
Citation Format: Shaun D. Fontaine, Gary W. Ashley, Peter J. Houghton, Raushan Kurmasheva, Morgan Diolati, Alan Ashworth, Daniel V. Santi. A very long-acting poly(ADP-ribose) polymerase inhibitor [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-060.
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Affiliation(s)
| | | | | | | | - Morgan Diolati
- 3UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA
| | - Alan Ashworth
- 3UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA
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Ghilu S, Li Q, Fontaine SD, Santi DV, Kurmasheva RT, Zheng S, Houghton PJ. Prospective use of the single-mouse experimental design for the evaluation of PLX038A. Cancer Chemother Pharmacol 2020; 85:251-263. [PMID: 31927611 PMCID: PMC7039322 DOI: 10.1007/s00280-019-04017-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022]
Abstract
PURPOSE Defining robust criteria for drug activity in preclinical studies allows for fewer animals per treatment group, and potentially allows for inclusion of additional cancer models that more accurately represent genetic diversity and, potentially, allows for tumor sensitivity biomarker identification. METHODS Using a single-mouse design, 32 pediatric xenograft tumor models representing diverse pediatric cancer types [Ewing sarcoma (9), brain (4), rhabdomyosarcoma (10), Wilms tumor (4), and non-CNS rhabdoid tumors (5)] were evaluated for response to a single administration of pegylated-SN38 (PLX038A), a controlled-release PEGylated formulation of SN-38. Endpoints measured were percent tumor regression, and event-free survival (EFS). The correlation between response to PLX038A was compared to that for ten models treated with irinotecan (2.5 mg/kg × 5 days × 2 cycles), using a traditional design (10 mice/group). Correlations between tumor sensitivity, genetic mutations and gene expression were sought. Models showing no disease at week 20 were categorized as 'extreme responders' to PLX038A, whereas those with EFS less than 5 weeks were categorized as 'resistant'. RESULTS The activity of PLX038A was evaluable in 31/32 models. PLX038A induced > 50% volume regressions in 25 models (78%). Initial tumor volume regression correlated only modestly with EFS (r2 = 0.238), but sensitivity to PLX038A was better correlated with response to irinotecan when one tumor hypersensitive to PLX038A was omitted (r2 = 0.6844). Mutations in 53BP1 were observed in three of six sensitive tumor models compared to none in resistant models (n = 6). CONCLUSIONS This study demonstrates the feasibility of using a single-mouse design for assessing the antitumor activity of an agent, while encompassing greater genetic diversity representative of childhood cancers. PLX038A was highly active in most xenograft models, and tumor sensitivity to PLX038A was correlated with sensitivity to irinotecan, validating the single-mouse design in identifying agents with the same mechanism of action. Biomarkers that correlated with model sensitivity included wild-type TP53, or mutant TP53 but with a mutation in 53BP1, thus a defect in DNA damage response. These results support the value of the single-mouse experimental design.
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Affiliation(s)
- Samson Ghilu
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Qilin Li
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Shaun D Fontaine
- ProLynx LLC, 455 Mission Bay Blvd, South San Francisco, CA, 94158, USA
| | - Daniel V Santi
- ProLynx LLC, 455 Mission Bay Blvd, South San Francisco, CA, 94158, USA
| | - Raushan T Kurmasheva
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Siyuan Zheng
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - Peter J Houghton
- Greehey Children's Cancer Research Institute, UT Health San Antonio, 8403 Floyd Curl Drive, San Antonio, TX, 78229, USA.
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Ghilu S, Li Q, Fontaine SD, Santi DV, Kurmasheva RT, Zheng S, Houghton PJ. Abstract C001: Prospective use of the single mouse experimental design for evaluation of PLX038A against pediatric solid tumor models. Mol Cancer Ther 2019. [DOI: 10.1158/1535-7163.targ-19-c001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: In a previous analysis of >2100 in vivo pediatric xenograft tumor/drug studies (Murphy et al. Cancer Research, 2016), we reported that results from one mouse/treatment group gave essentially similar results for 67 drugs as 10 mice (solid tumor models) or 8 mice (leukemia models). The use of fewer animals per treatment group allows for inclusion of more cancer models that more accurately represent genetic diversity within an histology or between histology’s. Further, this increase in genetic diversity allows for tumor sensitivity biomarker identification, either within a tumor type (e.g. neuroblastoma) or independent of tumor lineage. Here we have used the single mouse design to evaluate a nanoformulated camptothecin analog, PLX038A, where SN-38 (the active metabolite of irinotecan) is released at a controlled rate. Additional objectives of the study were to determine the relationship between initial tumor volume regression and Event-Free Survival (EFS), and to mine genomics data on each tumor model with a goal to identify potential biomarkers that relate to drug sensitivity. Experimental Procedures: Pediatric patient derived xenografts (PDX) were grown subcutaneously, and treatment was administered when tumors were ~300mm3(mean 297 ±34 mm3; range 260-370 mm3). Models tested included rhabdomyosarcoma (Rh10, Rh18, Rh28, Rh30, Rh30R, Rh41, Rh65), Wilms tumors (KT-5, KT-10, KT-11, KT-13); and non-CNS rhabdoid tumors (KT-12, KT-14, KT-16, RBD1, RBD2) and cell line-derived xenografts (Ewing sarcoma lines ES-1, ES-4, ES-5, ES-6, EW-8, CHLA258, TC-71, SK-NEP-1). New models include RBD1 an atypical teratoid rhabdoid tumor established from a metastatic lung lesion, NCH-EWS-1, a Ewing sarcoma from a lung lesion, and S12-6321 was established from a patient with metastatic pleiomorphic xanthoastrocytoma. All tumors were used at low passage and authenticated by STR analysis against reference profiles developed by this group. Tumor models were selected for testing without reference to genetic or molecular characteristics, or sensitivity to irinotecan in previous testing. PLX038A was administered one time at a dose of 120 umol/kg by intraperitoneal injection. For 13 models, with data for the single agent irinotecan (2.5 mg/kg daily x 5 with cycle repeated at day 21), the correlation between tumor responsiveness to PX038A and irinotecan was examined. Results: The activity of single-dose PLX038A was evaluable in 30/31 models. PLX038A induced >50% volume regressions in 25 models (83%). EFS varied from 30 to >120 days dependent on the xenograft model. For 13 tumor models having complete regression, EFS times varied from 38 to >120 days, hence initial tumor volume regression correlated only modestly with EFS (r2= 0.453). Sensitivity to PLX038A was highly correlated with response to irinotecan (r2=0.729). Mutations in TP53BP1 were enriched in 6 sensitive tumor models compared to 4 resistant models. Conclusions: PLX038A was highly active in most xenograft models, and tumor sensitivity to PLX038A was highly correlated with sensitivity to irinotecan. Biomarkers that correlated with model sensitivity included wild type TP53, or mutant TP53 but with a mutation in TP53BP1, thus a defect in DNA damage response. These results support the value of the single mouse experimental design, and also support further development of PLX038 for pediatric clinical evaluation. Support: UO1CA199297, CA169368 and CA165995 (PJH) from NCI and CPRIT RR170055 (SZ).
Citation Format: Samson Ghilu, Qilin Li, Shaun D Fontaine, Daniel V. Santi, Raushan T. Kurmasheva, Siyuan Zheng, Peter J. Houghton. Prospective use of the single mouse experimental design for evaluation of PLX038A against pediatric solid tumor models [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C001. doi:10.1158/1535-7163.TARG-19-C001
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Affiliation(s)
| | - Qilin Li
- 1UT Health San Antonio, San Antonio, TX
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10
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Beckford Vera DR, Fontaine SD, VanBrocklin HF, Hearn BR, Reid R, Ashley GW, Santi DV. PET Imaging of the EPR Effect in Tumor Xenografts Using Small 15 nm Diameter Polyethylene Glycols Labeled with Zirconium-89. Mol Cancer Ther 2019; 19:673-679. [PMID: 31744896 DOI: 10.1158/1535-7163.mct-19-0709] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/18/2019] [Accepted: 11/12/2019] [Indexed: 11/16/2022]
Abstract
The goal was to develop and characterize a companion diagnostic for the releasable PEG40kDa∼SN-38 oncology drug, PLX038, that would identify tumors susceptible to high accumulation of PLX038. PEG conjugates of the zirconium ligand desferroxamine B (DFB) of similar size and charge to PLX038 were prepared that contained one or four DFB, as well as one that contained three SN-38 moieties and one DFB. Uptake and associated kinetic parameters of the 89Zr-labeled nanocarriers were determined in tumor and normal tissues in mice using μPET/CT imaging. The data were fit to physiologically based pharmacokinetic models to simulate the mass-time profiles of distribution of conjugates in the tissues of interest. The time-activity curves for normal tissues showed high levels at the earliest time of measurement due to vascularization, followed by a monophasic loss. In tumors, levels were initially lower than in normal tissues but increased to 9% to 14% of injected dose over several days. The efflux half-life in tumors was very long, approximately 400 hours, and tumor levels remained at about 10% injected dose 9 days after injection. Compared with diagnostic liposomes, the PEG nanocarriers have a longer serum half-life, are retained in tumors at higher levels, remain there longer, and afford higher tumor exposure. The small PEG40kDa nanocarriers studied here show properties for passive targeting of tumors that are superior than most nanoparticles and might be effective probes to identify tumors susceptible to similar size therapeutic nanocarriers such as PLX038.
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Affiliation(s)
- Denis R Beckford Vera
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California
| | | | - Henry F VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California
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11
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Fontaine SD, Santi AD, Reid R, Smith PC, Ashley GW, Santi DV. PLX038: a PEGylated prodrug of SN-38 independent of UGT1A1 activity. Cancer Chemother Pharmacol 2019; 85:225-229. [PMID: 31707444 DOI: 10.1007/s00280-019-03987-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/29/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE The purpose of this study was to determine the importance of UGT1A1 activity on the metabolism and pharmacokinetics of a releasable PEG ~ SN-38 conjugate, PLX038A. Irinotecan (CPT-11) is converted to the topoisomerase 1 inhibitor SN-38 by first-pass hepatic metabolism and is converted to its glucuronide SN-38G by UGT1A1. With diminished UGT1A1 activity, the high liver exposure to SN-38 can cause increased toxicity of CPT-11. In contrast, releasable PEG ~ SN-38 conjugates-such as PLX038-release SN-38 in the vascular compartment, and only low levels of SN-38 are expected to enter the liver by transport through the OATP1B1 transporter. METHODS We measured CPT-11 and PLX038A metabolites in plasma and bile, and determined pharmacokinetics of PLX038A in UGT1A-deficient and replete rats. RESULTS Compared to CPT-11, treatment of rats with PLX038A results in very low levels of biliary SN-38 and SN-38G, a low flux through UGT1A, and a low SN-38G/SN-38 ratio in plasma. Further, the pharmacokinetics of plasma PLX038A and SN-38 in rats deficient in UGT1A is unchanged compared to normal rats. CONCLUSIONS The disposition of PEGylated SN-38 is independent of UGT1A activity in rats, and PLX038 may find utility in full-dose treatment of patients who are UGT1A1*28 homozygotes or have metastatic disease with coincidental or incidental liver dysfunction.
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Affiliation(s)
- Shaun D Fontaine
- ProLynx, 455 Mission Bay Blvd. South, Suite 341, San Francisco, CA, 94158, USA
| | - Angelo D Santi
- ProLynx, 455 Mission Bay Blvd. South, Suite 341, San Francisco, CA, 94158, USA
| | - Ralph Reid
- ProLynx, 455 Mission Bay Blvd. South, Suite 341, San Francisco, CA, 94158, USA
| | - Philip C Smith
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Gary W Ashley
- ProLynx, 455 Mission Bay Blvd. South, Suite 341, San Francisco, CA, 94158, USA
| | - Daniel V Santi
- ProLynx, 455 Mission Bay Blvd. South, Suite 341, San Francisco, CA, 94158, USA.
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12
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Fontaine SD, Hann B, Reid R, Ashley GW, Santi DV. Species-specific optimization of PEG~SN-38 prodrug pharmacokinetics and antitumor effects in a triple-negative BRCA1-deficient xenograft. Cancer Chemother Pharmacol 2019; 84:729-738. [PMID: 31321449 DOI: 10.1007/s00280-019-03903-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 07/04/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE Optimal efficacy of a macromolecular prodrug requires balancing the rate of drug release with the rate of prodrug elimination. Since circulating macromolecules have different elimination rates in different species, a prodrug optimal for one species will likely not be for another. The objectives of this work were (a) to develop an approach to optimize pharmacokinetics of a PEG~SN-38 prodrug in a particular species, (b) to use the approach to predict the pharmacokinetics of various prodrugs of SN-38 in the mouse and human, and (c) to develop a PEG~SN-38 conjugate that is optimized for mouse tumor models. METHODS We developed models that describe the pharmacokinetics of a drug released from a prodrug by the relationship between the rates of drug release and elimination of the prodrug. We tested the model by varying the release rate of SN-38 from PEG~SN-38 conjugates in the setting of a constant prodrug elimination rate in the mouse. Finally, we tested the antitumor efficacy of a PEG~SN-38 optimized for the mouse. RESULTS Optimization of a PEG~SN-38 prodrug was achieved by adjusting the rate of SN-38 release such that the ratio of t1/2,β of released SN-38 to the t1/2 of prodrug elimination was 0.2-0.8. Using this approach, we could rationalize the efficacy of previous PEGylated SN-38 prodrugs in the mouse and human. Finally, a mouse-optimized PEG~SN-38 showed remarkable antitumor activity in BRCA1-deficient MX-1 xenografts; a single dose gave tumor regression, suppression, and shrinkage of massive tumors. CONCLUSIONS The efficacy of a macromolecular prodrug can be optimized for a given species by balancing the rate of drug release from the carrier with the rate of prodrug elimination.
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Affiliation(s)
- Shaun D Fontaine
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, CA, 94158, USA
| | - Byron Hann
- University of California San Francisco, 1450 3rd Street, San Francisco, CA, 94158, USA
| | - Ralph Reid
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, CA, 94158, USA
| | - Gary W Ashley
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, CA, 94158, USA
| | - Daniel V Santi
- ProLynx, 455 Mission Bay Boulevard South, Suite 341, San Francisco, CA, 94158, USA.
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13
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Spangler B, Fontaine SD, Shi Y, Sambucetti L, Mattis AN, Hann B, Wells JA, Renslo AR. A Novel Tumor-Activated Prodrug Strategy Targeting Ferrous Iron Is Effective in Multiple Preclinical Cancer Models. J Med Chem 2016; 59:11161-11170. [PMID: 27936709 PMCID: PMC5184369 DOI: 10.1021/acs.jmedchem.6b01470] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
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Here we describe
a new approach for tumor targeting in which augmented
concentrations of Fe(II) in cancer cells and/or the tumor microenvironment
triggers drug release from an Fe(II)-reactive prodrug conjugate. The
1,2,4-trioxolane scaffold developed to enable this approach can in
principle be applied to a broad range of cancer therapeutics and is
illustrated here with Fe(II)-targeted forms of a microtubule toxin
and a duocarmycin-class DNA-alkylating agent. We show that the intrinsic
reactivity/toxicity of the duocarmycin analog is masked in the conjugated
form and this greatly reduced toxicity in mice. This in turn permitted
elevated dosing levels, leading to higher systemic exposure and a
significantly improved response in tumor xenograft models. Overall
our results suggest that Fe(II)-dependent drug delivery via trioxolane
conjugates could have significant utility in expanding the therapeutic
index of a range of clinical and preclinical stage cancer chemotherapeutics.
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Affiliation(s)
- Benjamin Spangler
- Graduate Program in Chemistry and Chemical Biology, University of California-San Francisco , San Francisco, California 94158, United States.,Department of Pharmaceutical Chemistry, University of California-San Francisco , San Francisco, California 94158, United States
| | - Shaun D Fontaine
- Department of Pharmaceutical Chemistry, University of California-San Francisco , San Francisco, California 94158, United States
| | - Yihui Shi
- SRI International , Menlo Park, California 94025-3493, United States
| | - Lidia Sambucetti
- SRI International , Menlo Park, California 94025-3493, United States
| | | | - Byron Hann
- Preclinical Therapeutic Core, University of California-San Francisco , San Francisco, California 94158, United States
| | - James A Wells
- Department of Pharmaceutical Chemistry, University of California-San Francisco , San Francisco, California 94158, United States.,Department of Cellular and Molecular Pharmacology, University of California-San Francisco , San Francisco, California 94158, United States
| | - Adam R Renslo
- Department of Pharmaceutical Chemistry, University of California-San Francisco , San Francisco, California 94158, United States
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14
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Schneider EL, Hearn BR, Pfaff SJ, Fontaine SD, Reid R, Ashley GW, Grabulovski S, Strassberger V, Vogt L, Jung T, Santi DV. Approach for Half-Life Extension of Small Antibody Fragments That Does Not Affect Tissue Uptake. Bioconjug Chem 2016; 27:2534-2539. [DOI: 10.1021/acs.bioconjchem.6b00469] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eric L. Schneider
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | - Brian R. Hearn
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | - Samuel J. Pfaff
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | - Shaun D. Fontaine
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | - Ralph Reid
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | - Gary W. Ashley
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
| | | | | | - Lorenz Vogt
- Delenex Therapeutics AG, Wagistrasse
27, CH-8952 Schlieren, Germany
| | - Thomas Jung
- Delenex Therapeutics AG, Wagistrasse
27, CH-8952 Schlieren, Germany
| | - Daniel V. Santi
- ProLynx, 455 Mission Bay Blvd. South, Suite
145, San Francisco, California 94158, United States
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15
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Hearn BR, Jaishankar P, Sidrauski C, Tsai JC, Vedantham P, Fontaine SD, Walter P, Renslo AR. Structure-Activity Studies of Bis-O-Arylglycolamides: Inhibitors of the Integrated Stress Response. ChemMedChem 2016; 11:870-80. [DOI: 10.1002/cmdc.201500483] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/15/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Brian R. Hearn
- Department of Pharmaceutical Chemistry and; Small Molecule Discovery Center; University of California; San Francisco CA 94158 USA
| | - Priyadarshini Jaishankar
- Department of Pharmaceutical Chemistry and; Small Molecule Discovery Center; University of California; San Francisco CA 94158 USA
| | - Carmela Sidrauski
- Department of Biochemistry and Biophysics; Howard Hughes Medical Institute; University of California; San Francisco CA 94158 USA
| | - Jordan C. Tsai
- Department of Biochemistry and Biophysics; Howard Hughes Medical Institute; University of California; San Francisco CA 94158 USA
| | - Punitha Vedantham
- Department of Pharmaceutical Chemistry and; Small Molecule Discovery Center; University of California; San Francisco CA 94158 USA
| | - Shaun D. Fontaine
- Department of Pharmaceutical Chemistry and; Small Molecule Discovery Center; University of California; San Francisco CA 94158 USA
| | - Peter Walter
- Department of Biochemistry and Biophysics; Howard Hughes Medical Institute; University of California; San Francisco CA 94158 USA
| | - Adam R. Renslo
- Department of Pharmaceutical Chemistry and; Small Molecule Discovery Center; University of California; San Francisco CA 94158 USA
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16
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Lauterwasser EMW, Fontaine SD, Li H, Gut J, Katneni K, Charman SA, Rosenthal PJ, Bogyo M, Renslo AR. Trioxolane-Mediated Delivery of Mefloquine Limits Brain Exposure in a Mouse Model of Malaria. ACS Med Chem Lett 2015; 6:1145-9. [PMID: 26617969 DOI: 10.1021/acsmedchemlett.5b00296] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/02/2015] [Indexed: 11/29/2022] Open
Abstract
Peroxidic antimalarial agents including the sequiterpene artemisinins and the synthetic 1,2,4-trioxolanes function via initial intraparasitic reduction of an endoperoxide bond. By chemically coupling this reduction to release of a tethered drug species it is possible to confer two distinct pharmacological effects in a parasite-selective fashion, both in vitro and in vivo. Here we demonstrate the trioxolane-mediated delivery of the antimalarial agent mefloquine in a mouse malaria model. Selective partitioning of the trioxolane-mefloquine conjugate in parasitized erythrocytes, combined with effective exclusion of the conjugate from brain significantly reduced brain exposure as compared to mice directly administered mefloquine. These studies suggest the potential of trioxolane-mediated drug delivery to mitigate off-target effects of existing drugs, including the adverse neuropsychiatric effects of mefloquine use in therapeutic and chemoprophylactic settings.
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Affiliation(s)
| | | | - Hao Li
- Departments
of Pathology and Microbiology and Immunology, Stanford School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | | | - Kasiram Katneni
- Centre for Drug Candidate Optimisation,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Susan A. Charman
- Centre for Drug Candidate Optimisation,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | | | - Matthew Bogyo
- Departments
of Pathology and Microbiology and Immunology, Stanford School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
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17
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Mott BT, Eastman RT, Guha R, Sherlach KS, Siriwardana A, Shinn P, McKnight C, Michael S, Lacerda-Queiroz N, Patel PR, Khine P, Sun H, Kasbekar M, Aghdam N, Fontaine SD, Liu D, Mierzwa T, Mathews-Griner LA, Ferrer M, Renslo AR, Inglese J, Yuan J, Roepe PD, Su XZ, Thomas CJ. High-throughput matrix screening identifies synergistic and antagonistic antimalarial drug combinations. Sci Rep 2015; 5:13891. [PMID: 26403635 PMCID: PMC4585899 DOI: 10.1038/srep13891] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 08/07/2015] [Indexed: 01/22/2023] Open
Abstract
Drug resistance in Plasmodium parasites is a constant threat. Novel therapeutics, especially new drug combinations, must be identified at a faster rate. In response to the urgent need for new antimalarial drug combinations we screened a large collection of approved and investigational drugs, tested 13,910 drug pairs, and identified many promising antimalarial drug combinations. The activity of known antimalarial drug regimens was confirmed and a myriad of new classes of positively interacting drug pairings were discovered. Network and clustering analyses reinforced established mechanistic relationships for known drug combinations and identified several novel mechanistic hypotheses. From eleven screens comprising >4,600 combinations per parasite strain (including duplicates) we further investigated interactions between approved antimalarials, calcium homeostasis modulators, and inhibitors of phosphatidylinositide 3-kinases (PI3K) and the mammalian target of rapamycin (mTOR). These studies highlight important targets and pathways and provide promising leads for clinically actionable antimalarial therapy.
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Affiliation(s)
- Bryan T. Mott
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Richard T. Eastman
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Rajarshi Guha
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Katy S. Sherlach
- Department of Chemistry, Georgetown University, 37th and O St., NW, Washington, DC
| | - Amila Siriwardana
- Department of Chemistry, Georgetown University, 37th and O St., NW, Washington, DC
| | - Paul Shinn
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Crystal McKnight
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Sam Michael
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Norinne Lacerda-Queiroz
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Paresma R. Patel
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Pwint Khine
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Hongmao Sun
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Monica Kasbekar
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Nima Aghdam
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
- Department of Chemistry, Georgetown University, 37th and O St., NW, Washington, DC
| | - Shaun D. Fontaine
- Department of Pharmaceutical Chemistry, Small Molecule Discovery Center, University of California, San Francisco, CA
| | - Dongbo Liu
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Tim Mierzwa
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Lesley A. Mathews-Griner
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Marc Ferrer
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Adam R. Renslo
- Department of Pharmaceutical Chemistry, Small Molecule Discovery Center, University of California, San Francisco, CA
| | - James Inglese
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD
| | - Jing Yuan
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Paul D. Roepe
- Department of Chemistry, Georgetown University, 37th and O St., NW, Washington, DC
- Department of Biochemistry, Cellular and Molecular Biology and Center for Infectious Diseases, Georgetown University, 37th and O St., NW, Washington, DC
| | - Xin-zhuan Su
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Craig J. Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
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18
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Affiliation(s)
- Shaun D. Fontaine
- ProLynx, 455 Mission
Bay Blvd. South, Suite 145, San Francisco, California 94158, United States
| | - Ralph Reid
- ProLynx, 455 Mission
Bay Blvd. South, Suite 145, San Francisco, California 94158, United States
| | - Louise Robinson
- ProLynx, 455 Mission
Bay Blvd. South, Suite 145, San Francisco, California 94158, United States
| | - Gary W. Ashley
- ProLynx, 455 Mission
Bay Blvd. South, Suite 145, San Francisco, California 94158, United States
| | - Daniel V. Santi
- ProLynx, 455 Mission
Bay Blvd. South, Suite 145, San Francisco, California 94158, United States
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19
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Abstract
Ferrous iron-promoted reduction of a hindered peroxide bond underlies the antimalarial action of the 1,2,4-trioxane artemisinin and the 1,2,4-trioxolane arterolane. In appropriately designed systems, a 1,2,4-trioxolane ring can serve as a trigger to realize ferrous iron-dependent and parasite-selective drug delivery, both in vitro and in vivo. A stereocontrolled, expeditious (three steps), and efficient (67-71% overall yield) synthesis of 1,2,4-trioxolanes possessing the requisite 3″ substitution pattern that enables ferrous iron-dependent drug delivery is reported. The key synthetic step involves a diastereoselective Griesbaum co-ozonolysis reaction to afford primarily products with a trans relationship between the 3″ substituent and the peroxide bridge, as confirmed by X-ray structural analysis of a 3″-substituted 4-nitrobenzoate analogue.
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Affiliation(s)
- Shaun D Fontaine
- Department of Pharmaceutical Chemistry and Small Molecule Discovery Center, University of California, San Francisco , 1700 Fourth Street, San Francisco, California 94158, United States
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20
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Fontaine SD, Spangler B, Gut J, Lauterwasser EMW, Rosenthal PJ, Renslo AR. Drug delivery to the malaria parasite using an arterolane-like scaffold. ChemMedChem 2014; 10:47-51. [PMID: 25314098 DOI: 10.1002/cmdc.201402362] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2014] [Indexed: 11/06/2022]
Abstract
Antimalarial agents artemisinin and arterolane act via initial reduction of a peroxide bond in a process likely mediated by ferrous iron sources in the parasite. Here, we report the synthesis and antiplasmodial activity of arterolane-like 1,2,4-trioxolanes specifically designed to release a tethered drug species within the malaria parasite. Compared with our earlier drug delivery scaffolds, these new arterolane-inspired systems are of significantly decreased molecular weight and possess superior metabolic stability. We describe an efficient, concise and scalable synthesis of the new systems, and demonstrate the use of the aminonucleoside antibiotic puromycin as a chemo/biomarker to validate successful drug release in live Plasmodium falciparum parasites. Together, the improved drug-like properties, more efficient synthesis, and proof of concept using puromycin, suggests these new molecules as improved vehicles for targeted drug delivery to the malaria parasite.
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Affiliation(s)
- Shaun D Fontaine
- Department of Pharmaceutical Chemistry, University of California, San Francisco, 1700 4th Street, San Francisco, CA 94158 (USA)
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21
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Ko KS, Alexander MD, Fontaine SD, Biggs-Houck JE, La Clair JJ, Burkart MD. Synthetic studies on the mycolactone core. Org Biomol Chem 2010; 8:5159-65. [DOI: 10.1039/c0ob00540a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Alexander MD, Fontaine SD, La Clair JJ, Dipasquale AG, Rheingold AL, Burkart MD. Synthesis of the mycolactone core by ring-closing metathesis. Chem Commun (Camb) 2006:4602-4. [PMID: 17082856 DOI: 10.1039/b609408b] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The undecenolide core of mycolactone was synthesized by ring-closing metathesis and the structure confirmed using single-crystal X-ray diffraction techniques.
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Affiliation(s)
- Matthew D Alexander
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0358, USA
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