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Amaral Silva D, Le Merdy M, Alam KD, Wang Y, Bao Q, Malavia N, Burgess D, Lukacova V. Development of Mechanistic In Vitro-In Vivo Extrapolation to Support Bioequivalence Assessment of Long-Acting Injectables. Pharmaceutics 2024; 16:552. [PMID: 38675213 PMCID: PMC11054330 DOI: 10.3390/pharmaceutics16040552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/06/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Long-acting injectable (LAI) formulations provide sustained drug release over an extended period ranging from weeks to several months to improve efficacy, safety, and compliance. Nevertheless, many challenges arise in the development and regulatory assessment of LAI drug products due to a limited understanding of the tissue response to injected particles (e.g., inflammation) impacting in vivo performance. Mechanism-based in silico methods may support the understanding of LAI-physiology interactions. The objectives of this study were as follows: (1) to use a mechanistic modeling approach to delineate the in vivo performance of DepoSubQ Provera® and formulation variants in preclinical species; (2) to predict human exposure based on the knowledge gained from the animal model. The PBPK model evaluated different elements involved in LAI administration and showed that (1) the effective in vivo particle size is potentially larger than the measured in vitro particle size, which could be due to particle aggregation at the injection site, and (2) local inflammation is a key process at the injection site that results in a transient increase in depot volume. This work highlights how a mechanistic modeling approach can identify critical physiological events and product attributes that may affect the in vivo performance of LAIs.
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Affiliation(s)
- Daniela Amaral Silva
- Simulations Plus, Incorporated, 42505 10th Street West, Lancaster, CA 93534, USA; (M.L.M.); (V.L.)
| | - Maxime Le Merdy
- Simulations Plus, Incorporated, 42505 10th Street West, Lancaster, CA 93534, USA; (M.L.M.); (V.L.)
| | - Khondoker Dedarul Alam
- Division of Quantitative Methods and Modeling, Office of Research and Standards (ORS), Office of Generic Drugs (OGD), Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, MD 20993, USA; (K.D.A.); (Y.W.)
| | - Yan Wang
- Division of Quantitative Methods and Modeling, Office of Research and Standards (ORS), Office of Generic Drugs (OGD), Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, MD 20993, USA; (K.D.A.); (Y.W.)
| | - Quanying Bao
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA; (Q.B.); (N.M.); (D.B.)
| | - Nilesh Malavia
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA; (Q.B.); (N.M.); (D.B.)
| | - Diane Burgess
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA; (Q.B.); (N.M.); (D.B.)
| | - Viera Lukacova
- Simulations Plus, Incorporated, 42505 10th Street West, Lancaster, CA 93534, USA; (M.L.M.); (V.L.)
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Lai EPC, Li C. Actinide Decorporation: A Review on Chelation Chemistry and Nanocarriers for Pulmonary Administration. Radiat Res 2022; 198:430-443. [PMID: 35943882 DOI: 10.1667/rade-21-00004.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 07/05/2022] [Indexed: 11/03/2022]
Abstract
Chelation is considered the best method for detoxification by promoting excretion of actinides (Am, Np, Pu, Th, U) from the human body after internal contamination. Chemical agents that possess carboxylic acid or hydroxypyridinonate groups play a vital role in actinide decorporation. In this review article, we provide considerable background details on the chelation chemistry of actinides with an aim to formulate better decorporation agents. Nanocarriers for pulmonary delivery represent an exciting prospect in the development of novel therapies for actinide decorporation that both reduce toxic side effects of the agent and improve its retention in the body. Recent studies have demonstrated the benefits of using a nebulizer or an inhaler to administer chelating agents for the decorporation of actinides. Effective chelation therapy with large groups of internally contaminated people can be a challenge unless both the agent and the nanocarrier are readily available from strategic national stockpiles for radiological or nuclear emergencies. Sunflower lecithin is particularly adept at alleviating the burden of administration when used to form liposomes as a nanocarrier for pulmonary delivery of diethylenetriamine-pentaacetic acid (DTPA) or hydroxypyridinone (HOPO). Better physiologically-based pharmacokinetic models must be developed for each agent in order to minimize the frequency of multiple doses that can overload the emergency response operations.
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Affiliation(s)
- Edward P C Lai
- Ottawa-Carleton Chemistry Institute, Department of Chemistry, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Chunsheng Li
- Radiation Protection Bureau, Health Canada, Ottawa, ON K1A 1C1, Canada
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3
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Naeini SBM, Dadashzadeh S, Haeri A, Mahjoub MA, Javidi J, Vatankhah M. Multivesicular liposomes as a potential drug delivery platform for cancer therapy: A systematic review. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2021.102842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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4
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Alirezaie Alavijeh A, Barati M, Barati M, Abbasi Dehkordi H. The Potential of Magnetic Nanoparticles for Diagnosis and Treatment of Cancer Based on Body Magnetic Field and Organ-on-the-Chip. Adv Pharm Bull 2019; 9:360-373. [PMID: 31592054 PMCID: PMC6773933 DOI: 10.15171/apb.2019.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/18/2019] [Accepted: 05/20/2019] [Indexed: 12/12/2022] Open
Abstract
Cancer is an abnormal cell growth which tends to proliferate in an uncontrolled way and, in some cases, leads to metastasis. If cancer is left untreated, it can immediately cause death. The use of magnetic nanoparticles (MNPs) as a drug delivery system will enable drugs to target tissues and cell types precisely. This study describes usual strategies and consideration for the synthesis of MNPs and incorporates payload drug on MNPs. They have advantages such as visual targeting and delivering which will be discussed in this review. In addition, we considered body magnetic field to make drug delivery process more effective and safer by the application of MNPs and tumor-on-chip.
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Affiliation(s)
- Ali Alirezaie Alavijeh
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
| | - Mohammad Barati
- Department of Applied Chemistry, Faculty of Chemistry, University of Kashan, Kashan, Iran
| | - Meisam Barati
- Student Research Committee, Department of Cellular and Molecular Nutrition, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hussein Abbasi Dehkordi
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
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5
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Giers MB, McLaren AC, Plasencia JD, Frakes D, McLemore R, Caplan MR. Spatiotemporal quantification of local drug delivery using MRI. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2013; 2013:149608. [PMID: 23710248 PMCID: PMC3655453 DOI: 10.1155/2013/149608] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 11/18/2022]
Abstract
Controlled release formulations for local, in vivo drug delivery are of growing interest to device manufacturers, research scientists, and clinicians; however, most research characterizing controlled release formulations occurs in vitro because the spatial and temporal distribution of drug delivery is difficult to measure in vivo. In this work, in vivo magnetic resonance imaging (MRI) of local drug delivery was performed to visualize and quantify the time resolved distribution of MRI contrast agents. Three-dimensional T1 maps (generated from T1-weighted images with varied TR) were processed using noise-reducing filtering. A segmented region of contrast, from a thresholded image, was converted to concentration maps using the equation 1/T1=1/T1,0+R1C, where T1,0 and T1 are the precontrast and postcontrast T1 map values, respectively. In this technique, a uniform estimated value for T 1,0 was used. Error estimations were performed for each step. The practical usefulness of this method was assessed using comparisons between devices located in different locations both with and without contrast. The method using a uniform T1,0, requiring no registration of pre- and postcontrast image volumes, was compared to a method using either affine or deformation registrations.
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Affiliation(s)
- Morgan B. Giers
- Center for Interventional Biomaterials, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
| | - Alex C. McLaren
- Center for Interventional Biomaterials, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
- Banner Good Samaritan Medical Center, 901 E Willetta Street, 2nd Floor, Phoenix, AZ 85006, USA
| | - Jonathan D. Plasencia
- Image Processing Application Laboratory, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
| | - David Frakes
- Image Processing Application Laboratory, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
| | - Ryan McLemore
- Center for Interventional Biomaterials, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
- Banner Good Samaritan Medical Center, 901 E Willetta Street, 2nd Floor, Phoenix, AZ 85006, USA
| | - Michael R. Caplan
- Center for Interventional Biomaterials, School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA
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6
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Colombo M, Carregal-Romero S, Casula MF, Gutiérrez L, Morales MP, Böhm IB, Heverhagen JT, Prosperi D, Parak WJ. Biological applications of magnetic nanoparticles. Chem Soc Rev 2012; 41:4306-34. [PMID: 22481569 DOI: 10.1039/c2cs15337h] [Citation(s) in RCA: 699] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this review an overview about biological applications of magnetic colloidal nanoparticles will be given, which comprises their synthesis, characterization, and in vitro and in vivo applications. The potential future role of magnetic nanoparticles compared to other functional nanoparticles will be discussed by highlighting the possibility of integration with other nanostructures and with existing biotechnology as well as by pointing out the specific properties of magnetic colloids. Current limitations in the fabrication process and issues related with the outcome of the particles in the body will be also pointed out in order to address the remaining challenges for an extended application of magnetic nanoparticles in medicine.
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Affiliation(s)
- Miriam Colombo
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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Terreno E, Boffa C, Menchise V, Fedeli F, Carrera C, Castelli DD, Digilio G, Aime S. Gadolinium-doped LipoCEST agents: a potential novel class of dual 1H-MRI probes. Chem Commun (Camb) 2011; 47:4667-9. [PMID: 21409237 DOI: 10.1039/c1cc10172b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel class of paramagnetic liposome-based systems acting as dual T(1) and CEST (1)H-MRI contrast agents is described. The vesicles contain a shift reagent in the aqueous core and a Gd-complex on the external surface conjugated through a biodegradable linker. As such, the probe can generate T(1) contrast only, but after the cleavage and removal of the Gd-coating, the CEST contrast is switched on.
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Affiliation(s)
- Enzo Terreno
- Department of Chemistry IFM and Molecular & Preclinical Imaging Centres, University of Torino, via Nizza 52, 10126, Torino, Italy.
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Singamaneni S, Bliznyuk VN, Binek C, Tsymbal EY. Magnetic nanoparticles: recent advances in synthesis, self-assembly and applications. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11845e] [Citation(s) in RCA: 383] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Hajdo L, Szulc AB, Klajnert B, Bryszewska M. Metabolic limitations of the use of nucleoside analogs in cancer therapy may be overcome by application of nanoparticles as drug carriers: A review. Drug Dev Res 2010. [DOI: 10.1002/ddr.20390] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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10
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Noninvasive visualization of in vivo release and intratumoral distribution of surrogate MR contrast agent using the dual MR contrast technique. Biomaterials 2010; 31:7132-8. [PMID: 20580427 DOI: 10.1016/j.biomaterials.2010.06.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Accepted: 06/01/2010] [Indexed: 11/24/2022]
Abstract
A direct evaluation of the in vivo release profile of drugs from carriers is a clinical demand in drug delivery systems, because drug release characterized in vitro correlates poorly with in vivo release. The purpose of this study is to demonstrate the in vivo applicability of the dual MR contrast technique as a useful tool for noninvasive monitoring of the stability and the release profile of drug carriers, by visualizing in vivo release of the encapsulated surrogate MR contrast agent from carriers and its subsequent intratumoral distribution profile. The important aspect of this technique is that it incorporates both positive and negative contrast agents within a single carrier. GdDTPA, superparamagnetic iron oxide nanoparticles, and 5-fluorouracil were encapsulated in nano- and microspheres composed of poly(D,L-lactide-co-glycolide), which was used as a model carrier. In vivo studies were performed with orthotopic xenograft of human breast cancer. The MR-based technique demonstrated here has enabled visualization of the delivery of carriers, and release and intratumoral distribution of the encapsulated positive contrast agent. This study demonstrated proof-of-principle results for the noninvasive monitoring of in vivo release and distribution profiles of MR contrast agents, and thus, this technique will make a great contribution to the field.
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Abstract
Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed.
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Affiliation(s)
- S Kevin Li
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Cincinnati, Cincinnati, OH 45267, USA.
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12
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Determination of water permeability of paramagnetic liposomes of interest in MRI field. J Inorg Biochem 2008; 102:1112-9. [DOI: 10.1016/j.jinorgbio.2008.01.025] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Revised: 01/18/2008] [Accepted: 01/18/2008] [Indexed: 11/21/2022]
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13
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Nieh MP, Katsaras J, Qi X. Controlled release mechanisms of spontaneously forming unilamellar vesicles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:1467-71. [PMID: 18394425 DOI: 10.1016/j.bbamem.2008.02.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 02/26/2008] [Accepted: 02/26/2008] [Indexed: 11/17/2022]
Abstract
Spontaneously forming small unilamellar vesicles (SULVs) are easy to prepare and show great promise for use in delivering therapeutic payloads. We report of SULVs made up of the ternary phospholipid mixture, dimyristoyl-phosphatidylcholine (DMPC), dihexanoyl-phosphatidylcholine (DHPC) and dimyristoyl-phosphatidylglycerol (DMPG), which have been characterized by small angle neutron scattering (SANS). These low-polydispersity (0.14-0.19) SULVs range in size (i.e., radius) from 110 to 215 A and are capable of entrapping, and subsequently releasing, hydrophilic molecules (e.g., fluorescent dyes and quenchers) in a controlled fashion over two different temperature ranges. The low-temperature release mechanism involves the SULVs transforming into discoidal micelles, with an onset temperature (T(o)) of ~32 degrees C, while the high-temperature release mechanism is more gradual, presumably the result of defects formed through the continuous dissolution of DHPC into solution. Both of these mechanisms differ from other, previously reported thermosensitive liposomes.
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Affiliation(s)
- Mu-Ping Nieh
- Canadian Neutron Beam Centre, Steacie Institute for Molecular Sciences, National Research Council Canada, Chalk River Laboratory, Chalk River, ON, Canada.
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Diab R, Degobert G, Hamoudeh M, Dumontet C, Fessi H. Nucleoside analogue delivery systems in cancer therapy. Expert Opin Drug Deliv 2007; 4:513-31. [PMID: 17880274 DOI: 10.1517/17425247.4.5.513] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Nucleoside analogues (NAs) are important agents in the treatment of hematological malignancies. They are prodrugs that require activation by phosphorylation. Their rapid catabolism, cell resistance and overdistribution in the body jeopardize nucleoside analogue chemotherapy. Accordingly, therapeutic doses of NAs are particularly high and regularly have to be increased, resulting in severe toxicity and narrow therapeutic index. The major challenge is to concentrate the drug at the tumour site, avoiding its distribution to normal tissues. New drug carriers and biomaterials are being developed to overcome some of these obstacles. This review highlights novel NA delivery systems and discusses new technologies that could improve NA cancer therapy.
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Affiliation(s)
- Roudayna Diab
- School of Pharmacy, Université Lyon 1-ESCPE - UMR 5007, Laboratoire d'Automatique et de Génie des Procédés, Bât. 308 G, 43, Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France
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Brockmann MA, Kemmling A, Groden C. Current issues and perspectives in small rodent magnetic resonance imaging using clinical MRI scanners. Methods 2007; 43:79-87. [PMID: 17720566 DOI: 10.1016/j.ymeth.2007.07.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2007] [Accepted: 07/10/2007] [Indexed: 12/16/2022] Open
Abstract
Small rodents such as mice and rats are frequently used in animal experiments for several reasons. In the past, animal experiments were frequently associated with invasive methods and groups of animals had to be killed to perform longitudinal studies. Today's modern imaging techniques such as magnetic resonance imaging (MRI) allow non-invasive longitudinal monitoring of multiple parameters. Although only a few institutions have access to dedicated small animal MR scanners, most institutions carrying out animal experiments have access to clinical MR scanners. Technological advances and the increasing field strength of clinical scanners make MRI a broadly available and viable technique in preclinical in vivo research. This review provides an overview of current concepts, limitations, and recent studies dealing with small animal imaging using clinical MR scanners.
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Affiliation(s)
- Marc A Brockmann
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 61867 Mannheim, Germany.
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Ponce AM, Viglianti BL, Yu D, Yarmolenko PS, Michelich CR, Woo J, Bally MB, Dewhirst MW. Magnetic resonance imaging of temperature-sensitive liposome release: drug dose painting and antitumor effects. J Natl Cancer Inst 2007; 99:53-63. [PMID: 17202113 DOI: 10.1093/jnci/djk005] [Citation(s) in RCA: 227] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND In preclinical studies, lysolipid-based temperature-sensitive liposomes (LTSLs) containing chemotherapy drugs administered in combination with local hyperthermia have been found to increase tumor drug concentrations and improve antitumor efficacy of the drugs. We used a novel magnetic resonance imaging (MRI) method to measure the temporal and spatial patterns of drug delivery in a rat fibrosarcoma model during treatment with LTSLs containing doxorubicin and an MRI contrast agent (manganese) (Dox/Mn-LTSLs) administered at different times with respect to hyperthermia. METHODS Rats bearing 10- to 12-mm fibrosarcomas (n = 6-7 per group) were treated with Dox/Mn-LTSLs (at a dose of 5 mg doxorubicin/kg body weight) before and/or during 60 minutes of local tumor hyperthermia administered via a catheter inserted at the center of the tumor. Drug distribution was monitored continuously via MRI. Magnetic resonance changes were used to calculate intratumoral doxorubicin concentrations throughout treatment. Tumors were monitored until they reached five times their volume on the day of treatment or 60 days. Doxorubicin concentrations and times for tumors to reach five times their volume on the day of treatment were analyzed using the Kruskal-Wallis test and the Kaplan-Meier product-limit method, respectively. All statistical tests were two-sided. RESULTS Administration of Dox/Mn-LTSLs before, during, and both before and during hyperthermia yielded central, peripheral, and uniform drug distributions, respectively. Doxorubicin accumulated more quickly and reached higher concentrations in the tumor when Dox/Mn-LTSLs were administered during hyperthermia than when administered before hyperthermia (rate: 9.8 versus 1.8 microg/min, difference = 8.0 microg/min, 95% confidence interval [CI] = 6.8 to 12.8 microg/min, P = .003; concentration: 15.1 versus 8.0 ng/mg, difference = 7.1 ng/mg, 95% CI = 3.6 to 10.6 ng/mg, P = .028). LTSL administered during hyperthermia also yielded the greatest antitumor effect, with a median time for tumors to reach five times their volume on the day of treatment of 34 days (95% CI = 30 days to infinity) compared with 18.5 days (95% CI = 16 to 23 days) for LTSL before hyperthermia and 22.5 days (95% CI = 15 to 25 days) for LTSL before and during hyperthermia. CONCLUSIONS In this rat fibrosarcoma model, LTSLs were most effective when delivered during hyperthermia, which resulted in a peripheral drug distribution.
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Affiliation(s)
- Ana M Ponce
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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