Docetaxel In Plasma Research Articles

Bioanalytical method development and validation of docetaxel and carvacrol in mice plasma using LC-QqQ-MS/MS.

Present work describes the development of a liquid chromatography tandem mass spectrometry-based bioanalytical method for the reliable simultaneous quantification of docetaxel (DXL) and carvacrol (CVL) in the mice plasma. A rapid and sensitive bioanalytical method was developed and optimized in mice plasma using Paclitaxel as an internal standard. Validation of the bioanalytical method was performed according to the ICH M10 guideline covering the range of 9.62-1923.08 ng/mL in the mice plasma milleu at the low, mid, and high-quality control concentrations of 28.86 ng/mL, 961.54 ng/mL, and 1346.15 ng/mL, respectively for both the analytes. Validation parameters such as accuracy, precision, carryover-test, matrix effect, and reinjection reproducibility were carried out and were found in limits. Stability studies (Benchtop, autosampler, freeze-thaw, and long-term) were performed and found to be within limits. The developed bioanalytical method was found to be suitable for the simultaneous quantification of DXL and CVL in the mice plasma.

A sub-pharmacological test dose does not predict individual docetaxel exposure in prostate cancer patients.

Docetaxel is a cytotoxic drug used for first-line treatment of various malignancies. It has a narrow therapeutic index and shows wide interpatient variability in clearance and toxicity. Tools for individual dose optimization are needed to maximize efficacy and avoid toxicity. We performed a proof-of-concept study (EudraCT 2016-003785-77) to evaluate whether pharmacokinetics after a sub-pharmacological test dose of 1000µg docetaxel (millidose) could be used to predict therapeutic dose exposure. Thirty prostate cancer patients eligible for treatment with docetaxel as part of routine clinical care were included. An intravenous docetaxel millidose was administered 1-7 days prior to therapeutic docetaxel. After both doses plasma docetaxel concentrations were measured by ultra- high performance liquid chromatography-tandem mass spectrometry. The docetaxel clearance was estimated with non-linear mixed effects modeling. Geometric mean docetaxel clearance was 57.9L/h (GCV 78.6%) after admission of a millidose and 40.3L/h (GCV 60.7%) after admission of a therapeutic dose. The millidose and therapeutic dose in a single patient were not significantly correlated (Spearman's rho R = 0.02, P = 0.92). Docetaxel pharmacokinetics at milli- and therapeutic dose level showed insufficient correlation for individual dose optimization. However, the clearance of a docetaxel millidose and full dose are within the same order of magnitude. Therefore, docetaxel millidose pharmacokinetics could potentially facilitate prediction of docetaxel pharmacokinetics at a population level in situations where therapeutic dose levels are impractical, such as pharmacokinetic drug-drug interaction studies or pediatric studies.

Long-term efficacy, safety and PK data of TH1902 (sudocetaxel zendusortide) in solid tumors: A novel SORT1-targeting peptide-drug-conjugate (PDC).

3081 Background: TH1902 is a novel SORT1 targeting PDC. It exploits the natural function of SORT1, a scavenger receptor, which rapidly internalizes its natural ligands via endocytosis (internalization half-life ≤4 min). SORT1 is highly expressed in multiple solid tumors compared to normal healthy tissues making it an attractive target for rapid delivery of anti-cancer therapeutics. In this updated analysis, further data on long-term efficacy, safety and PK is presented from Parts 1&2 of Ph1 with focus on the 300 mg/m2 q3w. Due to safety observations in 6 patients (pts) enrolled at 420 mg/m2 dose level (Gr 3 neuropathy [n=2], Gr 4 neutropenia [n=2], Gr 3 ocular [n=1] and Gr 2 skin [n=3] toxicities, the dose was reduced to 300 mg/m2 in Part 2. Methods: Primary objective of the study was to characterize the safety/tolerability of TH1902. Part 1 (modified intrapatient dose escalation) included pts with recurrent/refractory advanced solid tumors (all comers) with no limit on number of previous therapies, including taxanes. Part 2 (dose expansion) included pts with known high SORT1 expression (e.g. OVC, endometrial, TNBC, melanoma). Results: Twenty-five heavily pretreated pts were enrolled in the 300 mg/m2 group. At least one TRAE was observed in 80% of pts. Grade 3 (Gr 3) events of interest were neuropathy (12%), keratitis (8%), anemia (8%), and neutropenia (4%), for an overall incidence of 32%. All grade neuropathy was 28%. Most TRAEs were mild to moderate severity and manageable with standard supportive care or dose reductions. Safety profile of TH1902 was different from that of docetaxel. PK measures of Cmax and AUC showed that exposure to free docetaxel was much lower than that of TH1902; Cmax = 0.58 μM for free docetaxel vs 30.4 μM for TH1902 and AUC24 = 3.1 h.nmol/mL for free docetaxel vs 74.8 h.nmol/mL for TH1902. Three pts exhibited RECIST 1.1 confirmed long-term stabilizations of disease, even after drug discontinuation, which ranged from 8 to 19 mos from treatment initiation, of which one OvC pt had overall PR (with RECIST 1.1 confirmed CR in target lesions) and remained on treatment for a total of 5 months. In addition, one endometrial cancer (part 1) was dose escalated from 60-360 mg/m2 and completed 11 cycles in total. Pt remained in SD during the 8 mos of treatment, up to time of consent withdrawal. All 4 pts had prior taxane exposure. Conclusions: TH1902 induces durable disease stabilization that lasts beyond treatment completion, suggesting a unique, multimodal mechanism of action (MOA) that differs from other cancer therapeutics. TH1902 has a manageable safety profile at 300mg/m2 with few Gr3 AEs. Low levels of free docetaxel in human plasma may in part explain the low rate of taxane related AEs (i.e. neutropenia, no alopecia). Next phase of the study involves dose optimization to further limit toxicity and improve efficacy. Clinical trial information: NCT04706962 .

Oral docetaxel plus encequidar – A pharmacokinetic model and evaluation against IV docetaxel

The development of optimized dosing regimens plays a crucial role in oncology drug development. This study focused on the population pharmacokinetic modelling and simulation of docetaxel, comparing the pharmacokinetic exposure of oral docetaxel plus encequidar (oDox + E) with the standard of care intravenous (IV) docetaxel regimen. The aim was to evaluate the feasibility of oDox + E as a potential alternative to IV docetaxel. The article demonstrates an approach which aligns with the FDA’s Project Optimus which aims to improve oncology drug development through model informed drug development (MIDD). The key question answered by this study was whether a feasible regimen of oDox + E existed. The purpose of this question was to provide an early GO / NO-GO decision point to guide drug development and improve development efficiency. Methods: A stepwise approach was employed to develop a population pharmacokinetic model for total and unbound docetaxel plasma concentrations after IV docetaxel and oDox + E administration. Simulations were performed from the final model to assess the probability of target attainment (PTA) for different oDox + E dose regimens (including multiple dose regimens) in relation to IV docetaxel using AUC over effective concentration (AUCOEC) metric across a range of effective concentrations (EC). A Go / No-Go framework was defined—the first part of the framework assessed whether a feasible oDox + E regimen existed (i.e., a PTA ≥ 80%), and the second part defined the conditions to proceed with a Go decision. Results: The overall population pharmacokinetic model consisted of a 3-compartment model with linear elimination, constant bioavailability, constant binding mechanics, and a combined error model. Simulations revealed that single dose oDox + E regimens did not achieve a PTA greater than 80%. However, two- and three-dose regimens at 600 mg achieved PTAs exceeding 80% for certain EC levels. Conclusion: The study demonstrates the benefits of MIDD using oDox + E as a motivating example. A population pharmacokinetic model was developed for the total and unbound concentration in plasma of docetaxel after administration of IV docetaxel and oDox + E. The model was used to simulate oDox + E dose regimens which were compared to the current standard of care IV docetaxel regimen. A GO / NO-GO framework was applied to determine whether oDox + E should progress to the next phase of drug development and whether any conditions should apply. A two or three-dose regimen of oDox + E at 600 mg was able to achieve non-inferior pharmacokinetic exposure to current standard of care IV docetaxel in simulations. A Conditional GO decision was made based on this result and further quantification of the “effective concentration” would improve the ability to optimise the dose regimen.

Profiling Docetaxel in Plasma and Urine Samples from a Pediatric Cancer Patient Using Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Combined with LC-MS/MS.

In recent years, therapeutic drug monitoring (TDM) has been applied in docetaxel (DOC)-based anticancer therapy to precisely control various pharmacokinetic parameters, including the concentration of DOC in biofluids (e.g., plasma or urine), its clearance, and its area under the curve (AUC). The ability to determine these values and to monitor DOC levels in biological samples depends on the availability of precise and accurate analytical methods that both enable fast and sensitive analysis and can be implemented in routine clinical practice. This paper presents a new method for isolating DOC from plasma and urine samples based on the coupling of microextraction and advanced liquid chromatography with tandem mass spectrometry (LC-MS/MS). In the proposed method, biological samples are prepared via ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) using ethanol (EtOH) and chloroform (Chl) as the desorption and extraction solvents, respectively. The proposed protocol was fully validated according to the Food and Drug Administration (FDA) and the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) requirements. The developed method was then applied to monitor the DOC profile in plasma and urine samples collected from a pediatric patient suffering from cardiac angiosarcoma (AS) with metastasis to lungs and mediastinal lymph nodes, who was receiving treatment with DOC at a dose of 30 mg/m2 body surface area. Due to the rarity of this disease, TDM was carried out to determine the exact levels of DOC at particular time points to ascertain which levels were conducive to maximizing the treatment's effectiveness while minimizing the drug's toxicity. To this end, the concentration-time profiles of DOC in the plasma and urine samples were determined, and the levels of DOC at specific time intervals up to 3 days after administration were measured. The results showed that DOC was present at higher concentrations in the plasma than in the urine samples, which is due to the fact that this drug is primarily metabolized in the liver and then eliminated with the bile. The obtained data provided information about the pharmacokinetic profile of DOC in pediatric patients with cardiac AS, which enabled the dose to be adjusted to achieve the optimal therapeutic regimen. The findings of this work demonstrate that the optimized method can be applied for the routine monitoring of DOC levels in plasma and urine samples as a part of pharmacotherapy in oncological patients.

Ritonavir-boosted antiretroviral therapy with paclitaxel: will it lead to boosted toxicity?

Ritonavir-boosted antiretroviral therapy with paclitaxel: will it lead to boosted toxicity?

Bile Acid Tethered Docetaxel-Based Nanomicelles Mitigate Tumor Progression through Epigenetic Changes.

In this study, we describe the engineering of sub-100 nm nanomicelles (DTX-PC NMs) derived from phosphocholine derivative of docetaxel (DTX)-conjugated lithocholic acid (DTX-PC) and poly(ethylene glycol)-tethered lithocholic acid. Administration of DTX-PC NMs decelerate tumor progression and increase the mice survivability compared to Taxotere (DTX-TS), the FDA-approved formulation of DTX. Unlike DTX-TS, DTX-PC NMs do not cause any systemic toxicity and slow the decay rate of plasma DTX concentration in rodents and non-rodent species including non-human primates. We further demonstrate that DTX-PC NMs target demethylation of CpG islands of Sparcl1 (a tumor suppressor gene) by suppressing DNA methyltransferase activity and increase the expression of Sparcl1 that leads to tumor regression. Therefore, this unique system has the potential to improve the quality of life in cancer patients and can be translated as a next-generation chemotherapeutic.

Bile Acid Tethered Docetaxel‐Based Nanomicelles Mitigate Tumor Progression through Epigenetic Changes

AbstractIn this study, we describe the engineering of sub‐100 nm nanomicelles (DTX‐PC NMs) derived from phosphocholine derivative of docetaxel (DTX)‐conjugated lithocholic acid (DTX‐PC) and poly(ethylene glycol)‐tethered lithocholic acid. Administration of DTX‐PC NMs decelerate tumor progression and increase the mice survivability compared to Taxotere (DTX‐TS), the FDA‐approved formulation of DTX. Unlike DTX‐TS, DTX‐PC NMs do not cause any systemic toxicity and slow the decay rate of plasma DTX concentration in rodents and non‐rodent species including non‐human primates. We further demonstrate that DTX‐PC NMs target demethylation of CpG islands of Sparcl1 (a tumor suppressor gene) by suppressing DNA methyltransferase activity and increase the expression of Sparcl1 that leads to tumor regression. Therefore, this unique system has the potential to improve the quality of life in cancer patients and can be translated as a next‐generation chemotherapeutic.

Association of plasma docetaxel levels with ABCB1 gene polymorphisms and tumour response in locally advanced breast cancer patients of South India on neo-adjuvant chemotherapy.

Genetic factors could be attributed to the variability in docetaxel plasma levels and its subsequent therapeutic response. The objectives of this study were to assess the effect of ABCB1 gene polymorphisms [SNPs rs1045642 (C3435T) and rs1128503 (C1236T)] on docetaxel plasma levels and also to analyze the influence of docetaxel plasma levels on tumour response in the ethnically distinct South Indian population. 104 locally advanced breast cancer (LABC) patients on docetaxel-based neo-adjuvant chemotherapy (NACT) were included. The plasma docetaxel levels were estimated using the validated reverse phase liquid chromatography with mass spectrometry (LC-MS/MS). DNA was extracted (phenol-chloroform extraction method) and the real-time PCR system using validated TaqMan® SNP genotyping assay method was used for genotyping. Tumour response was assessed by RECIST criteria based on the MRI images. Patients with "CT/TT" genotype of the SNP C1236T had a C0/Ct ratio of 1.6 times higher than those with "CC" genotype (13.5 ± 6.5 vs 8.3 ± 3.1, p = 0.002). Though not significant, patients with "CT/TT" genotype had greater initial plasma concentration (C0) and area under the plasma concentration-time curve (AUC0-t). Conversely, the SNP C3435T was not associated with the plasma docetaxel levels. Furthermore, the C0 and normalized C0 were found to be higher in tumour responders compared to non-responders (p < 0.05). The plasma levels of docetaxel were significantly influenced by the SNP C1236T of ABCB1 gene coding for the MDR1 transporter (P-glycoprotein). The plasma levels of docetaxel were also found to influence its therapeutic effect.

Simultaneous Determination of Docetaxel and Celecoxib in Porous Microparticles and Rat Plasma by Liquid-Liquid Extraction and HPLC with UV Detection: in vitro and in vivo Validation and Application.

A simple, rapid, sensitive, and reliable HPLC method with UV detection was developed and validated for simultaneous quantitation of docetaxel and celecoxib and paclitaxel for dissolution characterization and pharmacokinetic studies. The HPLC assay was performed isocratically on a reversed-phase C18 μ-Bondapack column using a mobile phase of acetonitrile:water (45:55, v/v) at a flow rate of 1.2 mL/min, and the analytes were detected at 230 nm. Paclitaxel was used as an internal standard for analysis of plasma samples following simple liquid-liquid extraction with n-hexane:isoamyl alcohol (97:3). The method was validated for specificity, linearity, sensitivity, precision, accuracy, robustness, and in vitro-in vivo application. The retention times for docetaxel, paclitaxel, and celecoxib were 10.94, 12.4, and 16.81 min, respectively. The standard curves covering 0.1-1 μg/mL and 0.05-4 μg/mL were linear using dissolution medium and rat plasma, respectively. The limit of quantitation of the method was 50 ng/mL using 100 μL of rat plasma sample and injection of 50 μL of the residue. Within- and between-day precision and accuracy did not exceed 16.86% and 12.10%, respectively. This validated method was successfully used to quantify docetaxel and celecoxib simultaneously in the release study of docetaxel- celecoxib -loaded porous microparticles and pharmacokinetics studies. The methods were found to be simple, specific, precise, accurate, and reproducible. In this study, paclitaxel was used as the internal standard while dexamethasone, flutamide, and budesonide proved suitable alternative as an internal standard. Since docetaxel and celecoxib could be co-administered for the treatment of a wide range of cancers such as non-small cell lung carcinoma, the developed method is particularly advantageous for routine therapeutic drug monitoring and pharmacokinetic studies of these drugs.

Pharmacokinetics, safety, and early activity of a nanoparticle micellar formulation of docetaxel in women with metastatic breast cancer: Results of two randomized trials (phase I and II).

3526 Background: Docetaxel micellar (DM) is a nano-sized particle formulation of docetaxel in which a retinoic acid derivative is used as solubilizer with a high drug to excipient ratio possibly resulting in reduced systemic toxicity or hypersensitivity reactions due to the excipient. DM is given without standard use of premedication, avoiding steroid-associated immunosuppression. Here we present the pharmacokinetics (PK) after a single dose of DM or polysorbate-solubilized docetaxel (D) as well as safety and early activity including overall response rate (ORR) in female patients with metastatic breast cancer. Methods: The PK study was a two-cycle, cross-over study where 30 patients were included and randomized to either DM followed by D or D followed by DM, both given as a 1-hour intravenous infusion at a dose of 100mg/m2. The phase II study was a prospective, multicenter, open-label, third-party blinded, randomized, parallel group, active-controlled study including 200 patients to compare the early activity and safety of DM and D, both given as 100 mg/m2 1-hour intravenous infusion every 21 days (1 cycle) for a total of 6 cycles. Results: Bioequivalence of total docetaxel in plasma, AUC0-last and Cmax, was demonstrated for DM compared to D. The incidence of adverse events was higher in the D arm than in the DM arm for the majority of SOCs and PTs in the phase II study. Overall, Grade 3 or 4 AEs were reported for 82.7% of patients from DM arm and 99.0% of patients from D arm. Twelve (12.2%) patients in the DM arm and 24 (24.0%) patients in the D arm needed at least one dose reduction due to AEs. The primary efficacy endpoint in the phase II study was based on the assessment according to Response Evaluation Criteria in Soldid Tumors (RECIST) 1.1 and non-inferiority was not reached based on the pre-defined non-inferiority margin. A post-hoc analysis investigating the ORR based on tumour assessment at the end of chemotherapy, and non-inferiority of DM as compared to D was shown (ITT population). Conclusions: DM is bioequivalent to D regarding total drug in plasma and provides a docetaxel formulation that spares patients steroid premedication. An improved safety profile for DM compared to D was shown while additional efficacy data is needed for future development of DM. Eudra CT: 2012-005161-12 and 2013-004889-33. Clinical trial information: 2012-005161-12 and 2013-004889-33 .

ModraDoc006, an oral docetaxel formulation in combination with ritonavir (ModraDoc006/r), in metastasized castration-resistant prostate cancer (mCRPC): A multicenter phase I study.

79 Background: ModraDoc006 is a novel formulation of docetaxel and to enhance bioavailability, this tablet is co-administered with ritonavir (r), an inhibitor of cytochrome p450 3A4 and P-glycoprotein. The safety, anti-tumor activity and pharmacokinetics (PK) of ModraDoc006/r were investigated by dose-escalation in patients with mCRPC, to propose a recommended phase 2 dose (RP2D). Methods: Progressive mCRPC patients, who were treatment naïve or previously treated with either abiraterone or enzalutamide, received a maximum of 30 weekly cycles of ModraDoc006/r in a bi-daily once weekly (BIDW) schedule. Plasma docetaxel concentrations were determined at the first 2 cycles up to 48h after intake of ModraDoc006/r. Adverse events were evaluated using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.03. Serum Prostate Specific Antigen (PSA) levels were assessed every 6 weeks. Results: 23 patients were included, of whom 20 were evaluable for safety and PK. In 5 patients, the initial 30-20/100-100 dose was explored, with observation of one dose limiting toxicity (DLT) (grade 3 alanine aminotransferase increase). The next dose level of 30-20/200-200 resulted in 2 DLTs in 6 patients (grade 3 diarrhea and mucositis). Subsequently, two intermediate dose levels: 30-20/200-100 and 20-20/200-100 were explored in 6 and 3 patients. At the 30-20/200-100 dose, an adequate docetaxel exposure was achieved and 1 DLT (grade 3 diarrhea) was observed, with no DLTs at the 20-20/200-100 dose. Common treatment-related AEs (occurring in &gt; 30% of all patients) were diarrhea, nausea, vomiting, anorexia and fatigue. Five patients completed the maximum of 30 weekly treatments. In 10 patients, evaluable for anti-tumor activity after treatment with ≥9 cycles, 4 confirmed and 2 non-confirmed PSA responses ( &gt; 50% decrease) were observed. Conclusions: The RP2D of BIDW ModraDoc006/r in mCRPC was established as 30-20/200-100 mg. These results are encouraging for further development of ModraDoc006/r as a convenient, safe and effective alternative to IV docetaxel for mCRPC patients. A phase 2b study is currently being conducted. Clinical trial information: NCT03136640.

Abstract P3-10-07: Receptor-mediated chemotherapy using a new Docetaxel-peptide conjugate for Sortilin-positive triple-negative breast cancer

Abstract Background: Triple-negative breast cancer (TNBC) still lacks defined molecular biomarkers. Thus, targeting of specific gene/protein molecular signature of tumors emerged among the best anticancer strategies. Recently, increased expression of the cell surface receptor Sortilin was reported in tumors from patients with TNBC. Given Sortilin’s functions in protein internalization and trafficking; we developed a new Sortilin-targeted peptide-anticancer drug conjugate to treat Sortilin-positive breast cancer. The conjugate consists of 2 molecules of Docetaxel linked to a 17 amino acids peptide (TH-1902) which enables specific binding to Sortilin and subsequent internalization of TH-1902. Methods: MDA-MB-231 breast cancer cells were used as a TNBC model for in vitro and in vivo xenograft assays. Female CD-1 nude mice (Crl:NU-Foxn1nu) were used for xenograft tumor models, female athymic nude mice (Crl:NU(NCr)-Foxn1nu) were used in hematotoxicology and female Crl: CD-1 mice were used for pharmacokinetic evaluation. In vitro cell migration was assessed using the xCELLigence real-time system, whereas MTT assay was used for cell proliferation analysis. Apoptosis biomarkers expression was assessed by immunoblotting. The microtubule polymerization and depolymerization assay was performed by spectrofluorimetry, whereas fluorescent TH-peptide uptake was assessed by flow cytometry. Tissue microarrays included 9 normal adjacent tissues, 35 infiltrating ductal carcinomas (IDC), and 10 lymph nodes metastatic (LNM) carcinomas. Hematotoxicity assay allowed for blood neutrophil counts analysis in plasma samples. Results: Fluorescent Alexa488-labeled TH-peptide was found to be internalized in MDA-MB-231 cells and reduced by 72% upon transient SORT1 gene silencing. Alexa488-labeled TH-peptide uptake was inhibited by 65% in the presence of an excess of unlabeled TH-peptide and by the Sortilin ligands Neurotensin and Progranulin. TH-1902 exerted potent anti-proliferative and anti-migratory activities in vitro. TH-1902, like Docetaxel alone, triggered cell death mechanisms. The apoptotic and anti-migratory effects were reversed upon siRNA-mediated gene silencing of SORT1. Conjugation of Docetaxel to TH-peptide did not affect its capacity to alter microtubule stabilization, once internalized and cleaved from the TH-peptide within the cells. This further triggered the down-regulation of IL-6, Bcl-xL and mutant p53 pro-survival biomarkers. Sortilin immunolabeling showed very low levels in normal adjacent tissues, whereas high levels of Sortilin labeling were scored in IDC and LNM. In vivo, TH-1902 exhibited a greater tumor regression capacity with a prolonged survival in a murine MDA-MB-231 xenograft tumor model than did Docetaxel. Hematotoxic assays revealed that neutrophils count decreased significantly in Docetaxel-treated mice at MTD after 3 cycles, whereas they remained within normal limits in TH-1902-treated mice at an equivalent dose of Docetaxel even after six injections of TH-1902. Preliminary assessment of TH-1902 in normal CD-1 mice revealed that most Docetaxel remained associated with the peptide over the time course analyzed after a single IV bolus injection at 50 mg/kg. Absence of neutropenia in the presence of TH-1902 may be explained by the low levels of free Docetaxel in mouse plasma. Conclusions: The results demonstrate that Sortilin can be used as a target for treatment of TNBC. In addition, TH-1902 specifically internalized Docetaxel through a receptor-mediated mechanism exploiting Sortilin’s functions and significantly decreased the concentration of Docetaxel in normal cells. Overall, TH-1902 improved the efficacy and safety profiles compared to Docetaxel, which makes it a promising novel therapy for the treatment of TNBC. Citation Format: Michel Demeule, Cyndia Charfi, Jean-Christophe C Currie, Alain Larocque, Alain Zgheib, Christian Marsolais, Richard Béliveau, Borhane Annabi. Receptor-mediated chemotherapy using a new Docetaxel-peptide conjugate for Sortilin-positive triple-negative breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-10-07.

Development of a RP-HPLC method for analysis of docetaxel in tumor-bearing mice plasma and tissues following injection of docetaxel-loaded pH responsive targeting polymeric micelles.

Background and purpose:A simple, rapid, and sensitive reversed-phase high performance liquid chromatography (RP-HPLC) method based on liquid-liquid extraction was developed and validated for determination of docetaxel (DTX) in plasma and homogenate tissues of tumor-bearing mice.Experimental approach:Samples were spiked with celecoxib as the internal standard and separation was achieved on a μ-Bondapak C18 HPLC column. The mobile phase consisted of a mixture of acetonitrile/water (40/60 v/v) at flow rate of 1.2 mL/min and the effluent was monitored at 230 nm.Results:Calibration curves were linear over the concentration range of 0.1-10 μg/mL of DTX in plasma and 0.25-50 μg/mL in tissue homogenates with acceptable precision and accuracy. The mean recoveries of the drug from plasma extraction was 94.6 ± 1.44% while those of tissue homogenates ranged from 73.5 ± 3.2 to 85.3 ± 2.8% depending on the type of tissues examined. DTX was stable in biological samples with no evidence of degradation during 3 freeze-thaw cycles and two months of storage at -70 ± 15 °C. The developed HPLC method was applied to quantify DTX in the mouse plasma and tissues after intravenous administration of 7.5 mg equivalent DTX/kg dose of DTX-loaded folic acid-polyethylene glycol-heparin-tocopherol (FA-PEG-HEP-CA-TOC) micelle formulation to female Balb/c mice.Conclusion:A simple, sensitive, rapid, accurate, and prudent RP-HPLC method was developed, validated, and applied for DTX determination in plasma and tissues.

DETERMINAÇÃO DE DOCETAXEL E METABÓLITOS EM PLASMA POR UPLC-MS/MS: DESENVOLVIMENTO DE METODOLOGIA ANALÍTICA E APLICAÇÃO CLÍNICA

A highly sensitive ultra-performance liquid chromatography tandem mass spectrometry method for the determination of Docetaxel and metabolites (M1+M3) in human plasma samples was developed and validated. The method employs a liquid-liquid extraction and a reversed phase separation Acquity® C18 column BEH C18 (150 x 2.1 mm, 1.7 µm). Mobile phase was a mixture of formic acid 0.1% (eluent A) and acetonitrile plus 0.1% formic acid (eluent B) in isocratic mode. Total analytical run time was 7 min. The interval of method linearity interval was 50 to 3000 ng mL-1 for docetaxel and 5.0 to 300 ng mL-1, for M1+M3 metabolites. Intra-assay and inter-assay precision was coefficient of variation 2.5-15.7% and 5.9-12.6%, respectively and accuracy was 89.0-114.0%. The method was successfully applied in the measurement of docetaxel plasma levels and area under the curve calculation in 31 cancer patients, demonstrating adequate analytical performance for the clinical application in the therapeutic drug monitoring and pharmacokinetics studies.

Exposure to Docetaxel in the Elderly Patient Population: a Population Pharmacokinetic Study.

Docetaxel is commonly used in elderly patients, who are frequently diagnosed with prostate cancer. Although previous studies revealed no clinically relevant impact of older age on docetaxel pharmacokinetics (PK), this may be masked by indication. Metastatic castration-resistant prostate cancer (mCRPC) patients were reported to have approximately two-times lower systemic exposure compared to patients with other solid tumors. This study assessed the impact of older age on docetaxel PK, also considering the effect of indication on docetaxel PK. Prospectively collected docetaxel PK data from patients aged ≥70 was pooled with PK data from an earlier published multicenter study. A 3-compartment population PK model, including multiple covariates, was used to describe docetaxel plasma concentration-time data. We added the effect of prostate cancer (mCRPC and metastatic hormone-sensitive prostate cancer (mHSPC)) on clearance to this model. Hereafter, we evaluated the additional impact of older age on docetaxel clearance, using a significance threshold of p < 0.005. Docetaxel plasma concentration-time data from 157 patients were analyzed. Median age in the total cohort was 67years (range 31-87), with 49% of the total cohort aged ≥70. The impact of age on docetaxel clearance was statistically significant (p < 0.005). For a typical patient, a 10-year and 20-year increase of age led to a reduction in clearance of 17% and 34%, respectively. In this cohort study, age significantly and independently affected docetaxel clearance, showing lower docetaxel clearance in elderly patients. In our cohort, mCRPC and mHSPC patients both had higher clearance than patients with other solid tumors.

Immune-triggered cancer treatment by intestinal lymphatic delivery of docetaxel-loaded nanoparticle

The maximally tolerated dose (MTD) approach in conventional chemotherapy accompanies adverse effects, primarily due to high drug concentrations in the blood after intravenous administration and non-specific damages to highly proliferating cells, including immune cells. This causes the immune system to dysfunction. To rather boost intrinsic tumor-fighting immune capacity, we demonstrate a new oral route treatment regimen of docetaxel (DTX) without apparent toxicity. The DTX-loaded cationic solid lipid nanoparticles (DSLN-CSG) were coated with an anionic polymer conjugated with glycocholic acid. The resulting nanoparticles (DSLN-CSG, ~120 nm in diameter) were actively absorbed in the distal ileum mediated by interactions with the apical sodium bile acid transporter. The plasma DTX profile was sustained up to 24 h after a single oral dose and did not impair the functions of the immune system. In mouse models, daily oral DSLN-CSG administration inhibited the growth of existing tumors and tumor formation by medication prior to cancer cell inoculation. The extent of effects depended on the cancer cell lines of melanoma, colorectal adenocarcinoma, and breast carcinoma. It was most effective for melanoma in growth inhibition and in preventing tumor formation in mice. During the medication, the cytotoxic T cell population increased while the populations of tumor-associated macrophage and regulatory T cell declined. The low dose daily oral treatment may help patients with intermittent maintenance therapy between MTD cycles and prevent tumor recurrence after completing remission for certain tumors.

Effect of the Phragmitis Rhizoma Aqueous Extract on the Pharmacokinetics of Docetaxel in Rats.

Background:Traditionally, Phragmitis rhizoma has been prescribed to relive a fever, vomiting, dysuria, and constipation, and to promote secretion of fluids. In addition, recent studies have reported its efficacy as a diuretic and antiemetic. Our previous study demonstrated that the Phragmitis rhizoma aqueous extract (EPR) ameliorates docetaxel (DTX)-induced myelotoxicity. Aim and Objective:This study was aimed to investigate the effects of EPR on the pharmacokinetics of DTX in Sprague-Dawley rats.Materials and Methods:The animals received an intravenous injection of DTX (5 mg/kg) with or without oral EPR (100 mg/kg) pretreatment for 1 or 6 days. The pharmacokinetics of plasma DTX was analyzed using an ultra-performance liquid chromatography-tandem mass spectrometry system, and pharmacokinetic parameters were estimated via noncompartmental analysis.Results:Relative to the control group (DTX alone), EPR pretreatment did not affect significantly the overall profiles of plasma DTX levels. Consecutively pretreated EPR for 6 days slightly altered AUC0-t and Cmax of DTX by 122 and 145.9%, respectively, but these data did not reach the threshold of statistical significance (p > 0.05).Conclusion:These results indicate that DTX exposure may not be affected by EPR treatment at the dose level used in this study, suggesting that oral EPR can be used safely when taken with intravenously injected DTX. However, further studies under the stringent conditions are needed when chronic treatment of EPR and anticancer drug.

Preparation, characterization, and pharmacokinetics of liposomal docetaxel for oral administration

A docetaxel (DTX) liposomal formulation composed of egg phosphatidylcholine, sodium deoxycholate, and stearylamine was developed. Eudragit (0.5%) was coated to deliver the drug to the region between the distal small intestine and the colon. Lyophilized trehalose and mannitol were used as cryoprotectants because they preserve the particle integrity and good appearance. In vitro release studies showed that the amount of drug released from the coated liposomes was low in solution 1, which simulated the pH condition of the stomach. Especially during the average gastric emptying time, the amount of drug released decreased when Eudragit was added. The plasma DTX concentration was evaluated in pharmacokinetic studies. The plasma drug concentration after intravenous (i.v.) administration decreased rapidly within 120min. Free DTX formulated using Tween 80 and the lyophilized Eudragit-coated liposomal formulation were compared after oral administration. The oral liposomal formulation had a longer half-life (t1/2) and three-fold higher oral bioavailability. Thus, lyophilized Eudragit-coated liposomal DTX could be a promising therapy for various solid tumors to improve patient convenience and quality of life.

One-Step Solid Extraction for Simultaneous Determination of Eleven Commonly Used Anticancer Drugs and One Active Metabolite in Human Plasma by HPLC-MS/MS.

Therapeutic drug monitoring for anticancer drugs could timely reflect in vivo drug exposure, and it was a powerful tool for adjusting and maintaining drug concentration into a reasonable range, so that an enhanced efficacy and declined adverse reactions could be achieved. A liquid chromatography-tandem mass spectrometry method had been developed and fully validated for simultaneous determination of paclitaxel, docetaxel, vinblastine, vinorelbine, pemetrexed, carboplatin, etoposide, cyclophosphamide, ifosfamide, gemcitabine, irinotecan, and SN-38 (an active metabolite of irinotecan) in human plasma from cancer patients after intravenous drip of chemotherapy drugs. One-step solid-phase extraction was successfully applied using an Ostro sample preparation 96-well plate for plasma samples pretreated with acetonitrile containing 0.1% formic acid. Chromatographic separation was achieved on an Atlantis T3-C18 column (2.1 × 100 mm, 3.0 μm) with gradient elution using a mobile phase consisting of acetonitrile and 10 mM ammonium acetate plus 0.1% formic acid in water, and the flow rate was 0.25 mL/min. The Agilent G6410A triple quadrupole liquid chromatography-mass spectrometry system was operated under the multiple reaction monitoring mode with an electrospray ionization in the positive mode. Linear range was 25.0–2500.0 ng for paclitaxel, 10.0–1000.0 ng for docetaxel and SN-38, 100.0–10000.0 ng for vinorelbine and pemetrexed, 10.0–10000.0 ng for vinblastine and irinotecan, 1.0–1000.0 ng for cyclophosphamide and ifosfamide, 50.0–5000.0 ng for carboplatin, etoposide, and gemcitabine. Linearity coefficients of correlation were >0.99 for all analytes. The intraday and interday accuracy and precision of the method were within ±15.0% and less than 15%. The mean recovery and matrix effect as well as stability of all the analytes ranged from 56.2% to 98.9% and 85.2% to 101.3% as well as within ±15.0%. This robust and efficient method was successfully applied to implement therapeutic drug monitoring for cancer patients in clinical application.