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Objectives To assess the impact on the estimated glomerular filtration rate (eGFR) of different tenofovir disoproxil/emtricitabine dosing regimens for HIV pre-exposure prophylaxis (PrEP). Patients and methods We included in the study individuals with baseline eGFR > 50 mL/min/1.73 m2 who initiated PrEP in the ongoing ANRS-PREVENIR PrEP cohort. We retrospectively classified PrEP users in three groups: ‘on-demand’ (reported at ≥75% of study visits), ‘daily’ (≥75% of study visits) or ‘switches’. We compared the area under curve (AUC) of the eGFR variation from baseline (ΔeGFR) between groups using analysis of covariance, and assessed factors associated with a negative AUC of ΔeGFR. Results From May 2017 to October 2020, 1253 PrEP-naïve participants (98% of MSM) were included in the study with a median follow-up of 22 months. 499 (40%), 494 (39%) and 260 (21%) users were in the group daily, on-demand and switches, respectively, for a median number of pills taken per week of 6, 1.7 and 4. The mean AUC of the ΔeGFR was −1.09 mL/min/1.73 m2 in the daily PrEP group, −0.69 mL/min/1.73 m2 in the switches group and +0.18 mL/min/1.73 m2 with on-demand PrEP. In a model adjusted on baseline age and eGFR, the AUC of the ΔeGFR was significantly higher with on-demand PrEP compared to daily PrEP (P = 0.037). Independent factors associated with a negative AUC of ΔeGFR were a daily PrEP regimen, a switches regimen, an age > 40 years and a baseline eGFR≥90 mL/min/1.73 m². Conclusions On-demand PrEP dosing had a smaller impact on eGFR evolution than daily PrEP, but the difference was not clinically relevant.

The paradigm type I interferonopathy Aicardi-Goutières syndrome (AGS) is most typically characterized by severe neurological involvement. AGS is considered an immune-mediated disease, poorly responsive to conventional immunosuppression. Premised on a chronic enhancement of type I interferon signaling, JAK1/2 inhibition has been trialed in AGS, with clear improvements in cutaneous and systemic disease manifestations. Contrastingly, treatment efficacy at the level of the neurological system has been less conclusive. Here, we report our real-word approach study of JAK1/2 inhibition in 11 patients with AGS, providing extensive assessments of clinical and radiological status; interferon signaling, including in cerebrospinal fluid (CSF); and drug concentrations in blood and CSF. Over a median follow-up of 17 months, we observed a clear benefit of JAK1/2 inhibition on certain systemic features of AGS, and reproduced results reported using the AGS neurologic severity scale. In contrast, there was no change in other scales assessing neurological status; using the caregiver scale, only patient comfort, but no other domain of everyday-life care, was improved. Serious bacterial infections occurred in 4 out of the 11 patients. Overall, our data lead us to conclude that other approaches to treatment are urgently required for the neurologic features of AGS. We suggest that earlier diagnosis and adequate central nervous system penetration likely remain the major factors determining the efficacy of therapy in preventing irreversible brain damage, implying the importance of early and rapid genetic testing and the consideration of intrathecal drug delivery.

Purpose: p53 pathway alterations are key molecular events in glioblastoma (GBM). MDM2 inhibitors increase expression and stability of p53 and are presumed to be most efficacious in patients with TP53 wild-type and MDM2-amplified cancers. However, this biomarker hypothesis has not been tested in patients or patient-derived models for GBM.Experimental Design: We performed a preclinical evaluation of RG7112 MDM2 inhibitor, across a panel of 36 patient-derived GBM cell lines (PDCL), each genetically characterized according to their P53 pathway status. We then performed a pharmacokinetic (PK) profiling of RG7112 distribution in mice and evaluated the therapeutic activity of RG7112 in orthotopic and subcutaneous GBM models.Results: MDM2-amplified PDCLs were 44 times more sensitive than TP53-mutated lines that showed complete resistance at therapeutically attainable concentrations (avg. IC50 of 0.52 μmol/L vs. 21.9 μmol/L). MDM4-amplified PDCLs were highly sensitive but showed intermediate response (avg. IC50 of 1.2 μmol/L), whereas response was heterogeneous in TP53 wild-type PDCLs with normal MDM2/4 levels (avg. IC50 of 7.7 μmol/L). In MDM2-amplified lines, RG7112 restored p53 activity inducing robust p21 expression and apoptosis. PK profiling of RG7112-treated PDCL intracranial xenografts demonstrated that the compound significantly crosses the blood–brain and the blood–tumor barriers. Most importantly, treatment of MDM2-amplified/TP53 wild-type PDCL-derived model (subcutaneous and orthotopic) reduced tumor growth, was cytotoxic, and significantly increased survival.Conclusions: These data strongly support development of MDM2 inhibitors for clinical testing in MDM2-amplified GBM patients. Moreover, significant efficacy in a subset of non–MDM2-amplified models suggests that additional markers of response to MDM2 inhibitors must be identified. Clin Cancer Res; 22(5); 1185–96. ©2015 AACR.

S3: Evolution of MDM2 and TP53 status over time of 5 patients affected by MDM2-amplified GBM.

S6: MDM2, MDM4 and p53 protein level in the GBM cell lines of cohort #1 as determined by western blot

A) Genetic status of TP53, MDM2 and MDM4 from TCGA 2013 dataset. B) MDM2 mRNA expression level in relation to MDM2 copy number alterations from TCGA 2013 dataset.

Mt: TP53 homozygous mutation; Amp: amplified; Del: homozygous deletion, Wt: wild-type; NL: normal level.

Extraction from tumor cells, frozen tumor tissue and formalin fixed paraffin embedded (FFPE) tumor tissue; MDM2 gene copy number and TP53 mutational statuses; MDM2 gene copy number and TP53 mutational statuses; Western blot; Immunostaining in tumor or tissue cells

MDM2 status was determined by CGH and SNP array in the tumor of 696 GBM patients.

S5: MDM2, MDM4 and TP53 gene expression in the GBM cell lines of cohort #1 as determined by RT-qPCR.

Since the development of tyrosine kinase inhibitors (TKIs) targeting BCR/ABL1 and significantly improved outcomes on long-term disease-free survival in Philadelphia chromosome–positive (Ph+) acute ...

The development of BRAF and MEK inhibitors (BRAFi/MEKi) has led to major advances in melanoma treatment. However, the emergence of resistance mechanisms limits the benefit duration and a complete response occurs in less than 20% of patients receiving BRAFi ± MEKi. In this study, we evaluated the impact of an intermittent versus continuous dosing schedule of BRAF/MEK inhibition in a melanoma model mildly sensitive to a BRAF inhibitor. The combination of a BRAFi with three different MEKi was studied with a continuous or intermittent dosing schedule in vivo, in a xenografted melanoma model and ex vivo using histoculture drug response assays (HDRAs) of patient-derived xenografts (PDX). To further understand the underlying molecular mechanisms of therapeutic efficacy, a biomarker pharmacodynamic readout was evaluated. An equal impact on tumor growth was observed in monotherapy or bitherapy regimens whether we used continuous and intermittent dosing schedules, with no significant differences in biomarkers expression between the treatments. The antitumoral effect was mostly due to modulations of expression of cell cycle and apoptotic mediators. Moreover, ex vivo studies did not show significant differences between the dosing schedules. In this context, our preclinical and pharmacodynamic results converged to show the similarity between intermittent and continuous treatments with either BRAFi or MEKi alone or with the combination of both.

International audience; BackgroundThere are few data available regarding the use of on-demand pre-exposure prophylaxis (PrEP) for HIV prevention. We aimed to assess PrEP effectiveness, adherence, and safety in adults using daily or on-demand PrEP.MethodsWe conducted a prospective observational cohort study (ANRS PREVENIR) at 26 sites in the Paris region, France. We enrolled HIV-negative adults (aged ≥18 years) at high risk of HIV infection who were starting or continuing PrEP. PrEP was prescribed as a fixed-dose combination of tenofovir disoproxil and emtricitabine (245 mg and 200 mg, respectively, per pill). PrEP could be prescribed as a daily regimen with one pill per day or, in men who have sex with men (MSM) or in transgender women who have sex with men, as an on-demand regimen following the IPERGAY dosing recommendation. At enrolment and every 3 months thereafter, participants were tested for HIV and provided information regarding the PrEP dosing regimen used. Adherence to PrEP was assessed by self-report and by tenofovir diphosphate concentrations in dried blood spots. The primary outcome of HIV-1 incidence was assessed using Poisson regression among participants who started PrEP. This study is registered with ClinicalTrials.gov, NCT03113123, and EudraCT, 2016A0157744.FindingsBetween May 3, 2017, and May 2, 2019, 3082 people were assessed for eligibility and 3065 participants were enrolled. 3056 (99·7%) of 3065 participants reported using PrEP and were included in the analyses. The median age was 36 years (IQR 29–43), 1344 (44·0%) of 3056 participants were PrEP-naive, and 3016 (98·7%) were MSM. At enrolment, 1540 (50·5%) of 3049 participants opted for daily PrEP dosing and 1509 (49·5%) opted for on-demand PrEP dosing; these proportions remained stable during follow-up. Median follow-up was 22·1 months (IQR 15·9–29·7) and incidence of study discontinuation was 17·6 participants (95% CI 16·5–18·7) per 100 person-years. At the data cutoff on Sept 30, 2020, there had been six HIV-1 seroconversions (three participants using daily PrEP and three using on-demand PrEP; all were MSM) over 5623 person-years. Overall HIV-1 incidence was 1·1 cases (95% CI 0·4–2·3) per 1000 person-years, and did not differ between participants using daily PrEP and those using on-demand PrEP (incidence rate ratio 1·00, 95% CI 0·13–7·49; p=0·99). Four participants (two using daily PrEP and two using on-demand PrEP) discontinued PrEP due to treatment-related adverse events (nausea [n=2], vomiting and diarrhoea [n=1], and lumbar pain [n=1]).InterpretationIn this study, which enrolled mainly MSM, HIV-1 incidence on PrEP was low and did not differ between participants using daily PrEP and those using on-demand PrEP. On-demand PrEP therefore represents a valid alternative to daily PrEP for MSM, providing greater choice in HIV prevention.FundingANRS/Maladies Infectieuses Emergentes, Gilead Sciences, SIDACTION, and Région Ile de France.TranslationFor the French translation of the abstract see Supplementary Materials section.; ANRS/Maladies Infectieuses Emergentes, Gilead Sciences, SIDACTION, and Région Ile de France.

Background Tenofovir diphosphate (TFV-DP) concentration in dried blood spots (DBSs) is a reliable pharmacokinetics biomarker of adherence to tenofovir disoproxil fumarate (TDF). We aimed to use DBSs to estimate pill intake among participants using on-demand pre-exposure prophylaxis (PrEP) and to identify predictive factors associated with higher TFV-DP concentrations. Methods DBSs were collected at the last study visit of the open-label phase of the ANRS IPERGAY study, assessing on-demand oral TDF/emtricitabine for PrEP among MSM and transgender female participants. We quantified TFV-DP in DBSs centrally. We assessed correlation between pill count and TFV-DP concentration by Spearman correlation and explored associations between participant demographics, sexual behaviour and PrEP use during sexual intercourse (SI) with TFV-DP concentrations by univariate and multivariate logistic regression models. Results The median age of the 245 participants included in this study was 40 years, with a median body weight of 73 kg. Median (IQR) TFV-DP concentration reached 517 (128–868) fmol/punch, corresponding to an estimated intake of 8–12 tablets per month (2–3 doses per week). Only 39% of participants had a TFV-DP concentration above 700 fmol/punch. TFV-DP concentrations were moderately correlated with pill count (r: 0.59; P This is a pre-copyedited, author-produced PDF of an article accepted for publication in Journal of Antimicrobial Chemotherapy following peer review. The version of record [Estimated pill intake with on-demand PrEP with oral TDF/FTC using TFV-DP concentration in dried blood spots in the ANRS IPERGAY trial. Journal of Antimicrobial Chemotherapy (2021)] is available online at: https://doi.org/10.1093/jac/dkab253. Deposited by shareyourpaper.org and openaccessbutton.org. We've taken reasonable steps to ensure this content doesn't violate copyright. However, if you think it does you can request a takedown by emailing help@openaccessbutton.org.

Rationale Cytotoxic drug preparation in hospital pharmacies is associated with chronic occupational exposure leading to a risk of adverse effects. The objective was to develop and validate a quantification method for the following cytotoxic drugs in environmental wipe samples: cyclophosphamide, ifosfamide, cytarabine, dacarbazine, docetaxel, paclitaxel, doxorubicin, epirubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, methotrexate and pemetrexed. Methods The quantification method was developed using liquid chromatography coupled to tandem mass spectrometry and a wiping technique using viscose swabs. Linearity, accuracy, precision, limit of quantification, specificity and stability were assessed, from swab desorbed solution, to validate the analytical method, with respect to ICH guidelines. Environmental samples were collected by wiping five work surfaces of 225 cm2 with viscose swabs, during three days. Results The quantification method was linear over the calibration range with a lower limit of quantification ranging from 0.5 to 5.0 ng mL-1 depending on the cytotoxic drug. The intra-day and inter-day relative biases were below 1.5% and 13.5%, respectively. This method was successfully applied to surface-wipe sampling and environmental contaminations ranged from 0.7 to 1840.0 ng cm-2 for the most contaminated areas. Conclusions This quantification method for 14 cytotoxic drugs was successfully applied to environmental contamination monitoring and could therefore be a useful tool for monitoring and toxicological studies.

BACKGROUND Idelalisib is the first orally active selective phosphatidylinositol 3-kinase delta inhibitor approved by Food and Drug Administration and European Medicines Agency in 2014 for the treatment of several types of blood cancer. Idelalisib is widely used as a monotherapy or in combination with rituximab, bendamustine, or ofatumumab with a significant efficacy. However, idelalisib has shown increased risk of infection and a higher frequency of serious adverse events. It may be useful to determine idelalisib concentration in human plasma to adjust dose and to manage adverse effects in clinical practice. METHODS After a single-step protein precipitation of plasma samples, the chromatographic separation was performed using an ultra-high performance liquid chromatography system coupled with mass tandem spectrometry in a negative ionization mode using isotope-labeled internal standard. This method was validated by studies of its linearity, accuracy, imprecision, limit of quantification, recovery, matrix effect, selectivity, and stability. RESULTS The quantification method was linear from 10 to 2500 ng/mL with a 5 ng/mL lower limit of quantification that encompasses the clinical range of drug concentration. The intraday and interday imprecisions were below 8.1% and 11.4%, respectively. The recoveries and matrix effect of idelalisib were 85.6% ± 1.2% and 95.7% ± 3.0%, respectively, which are consistent, precise, and reproducible (coefficient of variation % < 15%). Peak plasma concentration and trough plasma concentration ranges of idelalisib reached 1591-1937 ng/mL and 256.3-303.3 ng/mL, respectively, in 3 follicular lymphoma patients treated with idelalisib 150 mg twice a day. CONCLUSIONS A robust and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated to quantify idelalisib concentration in human plasma. This method was effectively applied to 3 follicular lymphoma patients.

A sensitive liquid chromatography coupled with tandem mass spectrometry (MS/MS) method for the analysis in a small volume of plasma of 14 tyrosine kinase inhibitors currently used (imatinib, dasatinib, ibrutinib, ponatinib, trametinib, sunitinib, cobimetinib, dabrafenib, erlotinib, lapatinib, nilotinib, bosutinib, sorafenib, and vemurafenib) has been developed and validated. This multianalyte liquid chromatography coupled with MS/MS assay is of interest for anticancer drug combination therapy.After a simple protein precipitation of plasma samples, the chromatographic separation was performed using an ultra performance liquid chromatography system coupled with MS/MS in a positive ionization mode. The mobile phase consisted of a gradient elution of 10 mmol/L formate ammonium buffer containing 0.1% (vol/vol) formic acid (phase A) and acetonitrile with 0.1% (vol/vol) formic acid (phase B) at a flow rate of 300 μL/min.The analysis time was 5.0 minutes per run, and all analytes and internal standard eluted within 1.45-1.79 minutes. The calibration curves were linear over the range from 1 to 500 ng/mL for bosutinib, cobimetinib, dasatinib, ibrutinib, and trametinib, from 5 to 500 ng/mL for ponatinib and sunitinib; from 50 to 2500 ng/mL for lapatinib; from 750 to 100,000 ng/mL for vemurafenib, and from 10 to 2500 ng/mL for dabrafenib, erlotinib, imatinib, nilotinib, and sorafenib, with coefficients of correlation above 0.99 for all analytes. The intra- and interday imprecisions were below 14.36%.This method was successfully applied to therapeutic drug monitoring in clinical practice.

Purpose: Direct-acting antiviral agents have demonstrated their efficacy in treating HCV recurrence after liver transplantation and particularly the sofosbuvir/daclatasvir combination. Pharmacokinetic data on both calcineurin inhibitors and direct-acting antiviral exposure in liver transplant recipients remain sparse. Methods: Patients were enrolled from the ANRS CO23 CUPILT cohort. All patients treated with sofosbuvir/daclatasvir with or without ribavirin were included in this study when blood samples were available to estimate the clearance of immunosuppressive therapy before direct-acting antiviral initiation and during follow-up. Apparent tacrolimus and cyclosporine clearances were estimated from trough concentrations measured using validated quality control assays. Results: Sixty-seven mainly male patients (79%) were included, with a mean age of 57 years and mean MELD score of 8.2; 50 were on tacrolimus, 17 on cyclosporine. Ribavirin was combined with sofosbuvir/daclatasvir in 52% of patients. Cyclosporine clearance remained unchanged as well as tacrolimus clearance under the ribavirin-free regimen. Tacrolimus clearance increased 4 weeks after direct-acting antivirals and ribavirin initiation versus baseline (geometric mean ratio 1.81; 90% CI 1.30–2.52). Patients under ribavirin had a significantly higher fibrosis stage (> 2) (p = 0.02) and lower haemoglobin during direct-acting antiviral treatment (p = 0.02) which impacted tacrolimus measurements. Direct-acting antiviral exposure was within the expected range. Conclusion: Our study demonstrated that liver transplant patients with a recurrence of hepatitis C who are initiating ribavirin combined with a sofosbuvir-daclatasvir direct-acting antiviral regimen may be at risk of lower tacrolimus concentrations because of probable ribavirin-induced anaemia and higher fibrosis score, although there are no effects on cyclosporine levels. Trial registration: NCT 01944527., SCOPUS: ar.j, info:eu-repo/semantics/published

International audience; The blood-spinal cord barrier (BSCB) considerably limits the delivery and efficacy of treatments for spinal cord diseases. The blood-brain barrier can be safely opened with low-intensity pulsed ultrasound when microbubbles are simultaneously administered intravenously. This technique was tested on the BSCB in a rabbit model in this work. Twenty-three segments of spinal cord were sonicated with a 1-MHz unfocused pulsed ultrasound device and compared with non-sonicated segments. BSCB disruption was assessed using Evan's blue dye (EBD) extravasation. Tolerance was assessed by histologic analysis. An increased EBD concentration indicating BSCB disruption was clearly observed in sonicated segments compared with controls (p = 0.004). On one animal, which received 10 sonications, repetitive BSCB disruptions revealed no evidence of cumulative toxicity. BSCB can be disrupted using an unfocused pulsed ultrasound device in combination with microbubbles without neurotoxicity even in case of repeated sonications.

The therapeutic management of cancers has undergone considerable changes due to the emergence of genomics tools and tumor molecular deciphering. In this context, a dual pharmacological approach based on pharmacogenomic analyses and therapeutic drug monitoring is now part of the routine care in cancer management for personalized therapies. First, molecular and immune profiling of tumors allows the emergence of new pharmacological targets in common as well as in rare cancers. Second, pharmacogenomic analyses coupled to therapeutic drug monitoring guide the prescription by adjusting regimen and managing drug resistance.

A precise and accurate high-performance liquid chromatography (HPLC) quantification method of rifampicin in human plasma was developed and validated using ultraviolet detection after an automatized solid-phase extraction. The method was validated with respect to selectivity, extraction recovery, linearity, intra- and inter-day precision, accuracy, lower limit of quantification and stability. Chromatographic separation was performed on a Chromolith RP8 column using a mixture of 0.05 m acetate buffer pH 5.7-acetonitrile (35:65, v/v) as mobile phase. The compounds were detected at a wavelength of 335 nm with a lower limit of quantification of 0.05 mg/L in human plasma. Retention times for rifampicin and 6,7-dimethyl-2,3-di(2-pyridyl) quinoxaline used as internal standard were respectively 3.77 and 4.81 min. This robust and exact method was successfully applied in routine for therapeutic drug monitoring in patients treated with rifampicin.

To the editor: Langerhans cell sarcoma (LCS) is a rare histiocytic neoplasm with overt malignant cytological features and an aggressive clinical course.[1][1] Disseminated LCS carries a poor prognosis.[1][1] We report a case of a metastatic BRAF V600E -mutated LCS that dramatically improved after

We report the cases of a 39-year-old woman with chronic lymphocytic leukemia and a 21-year-old man with chronic granulomatous disease treated for cerebral aspergillosis. The patients required radical surgery for infection progression despite adequate isavuconazole plasma concentration or neurological complication. We thus decided to measure the brain isavuconazole concentration. These results suggest that the concentrations of isavuconazole obtained in the infected brain tissue clearly differ from those obtained in the normal brain tissue and the cerebrospinal fluid.

International audience; In situ carmustine wafers containing 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) are commonly used for the treatment of recurrent glioblastoma to overcome the brain-blood barrier. In theory, this chemotherapy diffuses into the adjacent parenchyma and the excipient degrades in maximum 8 weeks but no clinical data confirms this evolution, because patients are rarely operated again. A 75-year-old patient was operated twice for recurrent glioblastoma, and a carmustine wafer was implanted during the second surgery. Eleven months later, a third surgery was performed, revealing unexpected incomplete degradation of the wafer. 1H-Nuclear Magnetic Resonance was performed to compare this wafer to pure BCNU and to an unused copolymer wafer. In the used wafer, peaks corresponding to hydrophobic units of the excipient were no longer noticeable, whereas peaks of the hydrophilic units and traces of BCNU were still present. These surprising results could be related to the formation of a hydrophobic membrane around the wafer, thus interfering with the expected diffusion and degradation processes. The clinical benefit of carmustine wafers in addition to the standard radio-chemotherapy remains limited, and in vivo behavior of this treatment is not completely elucidated yet. We found that the wafer may remain after several months. Alternative strategies to deal with the blood–brain barrier, such as drug-loaded liposomes or ultrasound-opening, must be explored to offer larger drug diffusion or allow repetitive delivery.

The risk of central nervous system (CNS) dissemination in mantle cell lymphoma (MCL) is low and occurs late in the course of the disease. However, prognosis in such cases remains extremely poor despite high-dose antimetabolite chemotherapy. Among novel drugs used to treat relapsing MCL patients, ibrutinib, an oral inhibitor of Bruton tyrosine kinase, shows great promise. Here we report the clinical observation of 3 MCL patients with symptomatic CNS relapse treated with single-agent ibrutinib. All 3 patients had dramatic and rapid responses with almost immediate recovery from symptoms. We also confirmed that ibrutinib crosses the blood-brain barrier with parallel pharmacokinetic analyses in plasma and cerebrospinal fluid using a validated LC-MS/MS method. All responses were ongoing after 2 months to 1 year of follow-up.

Background Vemurafenib (Zelboraf) is a new tyrosine kinase inhibitor that selectively targets activated BRAF V600E gene and is indicated for the treatment of advanced BRAF mutation-positive melanoma. We developed a simple method for vemurafenib quantification using liquid chromatography-tandem mass spectrometry. A stability study of vemurafenib in human plasma was also performed. Methods (13)C(6)-vemurafenib was used as the internal standard. A single-step protein precipitation was used for plasma sample preparation. Chromatography was performed on an Acquity UPLC system (Waters) with chromatographic separation by the use of an Acquity UPLC BEH C18 column (2.1 × 50 mm, 1.7-mm particle size; Waters). Quantification was performed using the monitoring of multiple reactions of following transitions: m/z 488.2 → 381.0 for vemurafenib and m/z 494.2 → 387.0 for internal standard. Results This method was linear over the range from 1.0 to 100.0 mcg/mL. The lower limit of quantification was 0.1 mcg/mL for vemurafenib in plasma. Vemurafenib remained stable for 1 month at all levels tested, when stored indifferently at room temperature (20 °C), at +4 °C, or at -20 °C. This method was used successfully to perform a plasma pharmacokinetic study of vemurafenib in a patient after oral administration at a steady state. Conclusions This liquid chromatography-tandem mass spectrometry method for vemurafenib quantification in human plasma is simple, rapid, specific, sensitive, accurate, precise, and reliable.

Glioblastoma (GBM) is the most common primary malignant brain tumour in adults. Prognosis of GBM patients is poor with median overall survival around 15 months. Temozolomide is the chemotherapeutic agent used in the standard of care of newly diagnosed GBM patients relying on radiotherapy with concurrent chemotherapy followed by chemotherapy alone. Irinotecan has shown some efficacy in recurrent malignant gliomas. Bevacizumab has been combined with irinotecan in the treatment of recurrent GBM and with temozolomide in newly diagnosed GBM. As the efficacy of GBM treatments relies on their brain distribution through the blood brain barrier, the aim of the present preclinical work was to study, in in vivo models, the impact of bevacizumab on brain and tumor distribution of temozolomide and irinotecan. Our results show that bevacizumab pre-treatment was associated with a reduced temozolomide brain distribution in tumor-free mice. In tumor bearing mice, bevacizumab increased temozolomide tumor distribution, although not statistically significant. In both tumor-free and tumor-bearing mice, bevacizumab does not modify brain distribution of irinotecan and its metabolite SN-38. Bevacizumab impacts brain distribution of some anti-tumor drugs and potentially their efficacy in GBM. Further studies are warranted to investigate other therapeutic combination.

Central nervous system (CNS) dissemination occurs in 4.1% of mantle cell lymphoma (MCL) patients and clinically significant CNS involvement in chronic lymphocytic leukemia (CLL) patients reaches 4%. Ibrutinib, an orally administered Bruton’s tyrosine kinase (BTK) inhibitor, has shown substantial activity in CLL or MCL patients with CNS localization, and in primary central nervous system lymphoma (PCNSL). The drug efficacy to treat primary or secondary CNS impairments relies on its brain distribution through the blood–brain barrier (BBB), the aim of the present work was to study the brain distribution of ibrutinib using an in vivo mice model. Brain and plasma pharmacokinetics of ibrutinib were assessed in a healthy Swiss mice model. Brain accumulation of ibrutinib was evaluated through an escalation single-dose study and a multiple-dose study in whole brain and in its specific anatomic structures. Ibrutinib plasma and brain quantification was performed using a validated liquid-chromatography mass tandem spectrometry method. Maximal concentration of ibrutinib in plasma and brain were close thus showing that ibrutinib rapidly crosses the BBB in 0.29 h (0.2–0.32 h) [median (min–max)]. Ibrutinib brain exposure was also correlated to the dose, and correlated to plasma exposure. AUC0−t brain to AUC0−t plasma ratio average for ibrutinib was found to reach 0.7 and ibrutinib accumulates in the ventricle area. The high level of ibrutinib brain distribution supports the clinical efficacy of this drug in CNS localization of MCL, CLL or PCNSL.

Object The blood-brain barrier (BBB) is a major impediment to the intracerebral diffusion of drugs used in the treatment of gliomas. Previous studies have demonstrated that pulsed focused ultrasound (US) in conjunction with a microbubble contrast agent can be used to open the BBB. To apply the US-induced opening of the BBB in clinical practice, the authors designed an innovative unfocused US device that can be implanted in the skull and used to transiently and repeatedly open the BBB during a standard chemotherapy protocol. The goal of this preliminary work was to study the opening of the BBB induced by the authors' small unfocused US transducer and to evaluate the effects of the sonications on brain parenchyma. Methods Craniectomy was performed in 16 healthy New Zealand White rabbits; epidural application of a single-element planar ultrasonic transducer operating at 1 MHz was then used with a pulse-repetition frequency of 1 Hz, pulse lengths of 10–35 msec, in situ acoustic pressure levels of 0.3–0.8 MPa, and sonication for 60–120 seconds. SonoVue was intravenously injected during the US applications, and opening of the BBB was determined by detecting extravasation of Evans blue dye (EBD) in brain tissues, quantitative measurement of EBD with UV-visible spectrophotometry, and contrast enhancement after Gd injection in 4.7-T MRI. A histological study was performed to determine adverse effects. Results An opening of the BBB was observed over a large extent of the US beam in the brain corresponding to in situ pressures of greater than 0.2 MPa. The BBB opening observed was highly significant for both EBD (p < 0.01) and MRI Gd enhancement (p < 0.0001). The BBB opening was associated with minor adverse effects that included perivascular red blood cell extravasations that were less than 150 μm in size and not visible on MR images. Moderate edema was visible on FLAIR sequences and limited to the extent of the sonication field. Conclusions The results demonstrate that the BBB can be opened in large areas of the brain in rabbits with lowpower, pulsed, and unfocused US with limited damage to healthy tissue.

A sensitive and accurate liquid chromatography method with mass spectrometry detection was developed and validated for the quantification of temozolomide in mouse plasma and brain. Theophyllin was used as the internal standard. A single-step protein precipitation was used for plasma and brain sample preparation. The method was validated with respect to selectivity, extraction recovery, linearity, intra- and inter-day precision and accuracy, limit of quantification and stability. The method has a limit of quantification of 50 ng/mL for temozolomide in plasma and 125 ng/g in brain. This method was used successfully to perform brain and plasma pharmacokinetic studies of temozolomide in mice after intraperitoneal administration.

BACKGROUND The aim of this study was, using routine drug monitoring data, to identify patient characteristics that may influence everolimus (EVE) pharmacokinetic parameters and to develop a population pharmacokinetic model to predict EVE whole blood concentrations in cardiac recipients. METHODS Fifty-nine patients were enrolled in the prospective study. Patient's characteristics were recorded including biological covariates and treatments. CYP3A5 and ABCB1 polymorphisms were determined. Seven hundred seventy-five EVE blood samples were collected for routine drug monitoring. Population pharmacokinetic modeling was carried out using the nonlinear mixed-effects modeling program. Results were analyzed according to a 1-compartment pharmacokinetic model with linear absorption and elimination. The model was evaluated using a bootstrap method and a visual predictive check procedure. RESULTS The pharmacokinetic of EVE in cardiac recipients was best described by a 1-compartment model. Interindividual variability was best described by an exponential error model and residual error by a proportional plus additive error model. Estimation of EVE apparent clearance (3.33 ± 0.20 L/h) and apparent volume of distribution (146 ± 33 L) were in accordance with previously published data. Bilirubinemia and cyclosporine significantly influenced EVE clearance. Some covariates that were expected to influence EVE clearance, for example, ABCB1 and CYP3A5 polymorphisms, were not evidenced. No covariates influenced the volume of distribution of EVE. CONCLUSIONS This study is the first population pharmacokinetic model of EVE in heart transplantation patients. It allows a better description of the pharmacokinetics of EVE. The present population pharmacokinetic model allows estimating a priori and a posteriori EVE concentrations in cardiac recipients and could limit the over and under drug exposure in this population.

International audience; In the ANRS IPERGAY pre-exposure prophylaxis (PrEP) trial, a single dose of tenofovir disoproxil fumarate and emtricitabine was taken orally 2-24 h before sexual intercourse. A sub-study was conducted to assess the pharmacokinetics of tenofovir and emtricitabine in blood, saliva and rectal tissue following this initial oral intake. Methods: Plasma, PBMC, saliva and rectal tissue sampling was performed over 24 h in 12 seronegative men before enrolment in the ANRS IPERGAY trial, following a single dose of 600 mg tenofovir disoproxil fumarate/400 mg emtricitabine. Ex vivo HIV infectibility of rectal biopsies was also assessed. Results: The median plasma T max of tenofovir (median C max : 401 mg/L) and emtricitabine (median C max : 2868 mg/L) was obtained 1 h (range: 0.5-4) and 2 h (range: 1-4) after dosing, respectively. The median C 24 of tenofovir and emtricitabine was 40 and 63 mg/L, respectively. The median PBMC tenofovir diphosphate and emtricitabine triphosphate levels were 12.2 and 16.7 fmol/10 6 cells and 2800 and 2000 fmol/10 6 cells at 2 and 24 h after dosing, respectively. Saliva/plasma AUC 0-24 ratios were 2% and 17% for tenofovir and emtricitabine, respectively. Emtricitabine was detected in rectal tissue 30 min after dosing, whereas tenofovir was only detectable at 24 h. Ex vivo HIV infectibility assays of rectal biopsies showed partial protection after dosing (P,0.07). Discussion: A single high dose of oral tenofovir disoproxil fumarate/emtricitabine provides rapid and high blood levels of tenofovir and emtricitabine, with rapid diffusion of emtricitabine in saliva and rectal tissue.

International audience; Introduction: Glioblastomas (GBM) are the most common and aggressive primary malignant brain tumors in adults. The blood brain barrier (BBB) is a major limitation reducing efficacy of anti-cancer drugs in the treatment of GBM patients.Areas covered: Virtually all GBM recur after the first-line treatment, at least partly, due to invasive tumor cells protected from chemotherapeutic agents by the intact BBB in the brain adjacent to tumor. The passage through the BBB, taken by antitumor drugs, is poorly and heterogeneously documented in the literature. In this review, we have focused our attention on: (i) the BBB, (ii) the passage of chemotherapeutic agents across the BBB and (iii) the strategies investigated to overcome this barrier.Expert commentary: A better preclinical knowledge of the crossing of the BBB by antitumor drugs will allow optimizing their clinical development, alone or combined with BBB bypassing strategies, towards an increased success rate of clinical trials.

A precise and accurate high-performance liquid chromatography (HPLC) method with UV detection has been developed and validated for darunavir, a peptidic protease inhibitor. An internal standard, methylclonazepam, was added to 100 microL of plasma before a solid-phase extraction on C18 Bond Elut column. The eluted solutions were evaporated to dryness and reconstituted with 100 microL of mobile phase before being injected in the chromatographic system. The separation was performed on a C8 column using an acetonitrile and ultrapure water mixture (40:60, v/v) as mobile phase. All compounds were detected at a wavelength of 266 nm. The method was linear and validated over a concentration range of 0.25-20mg/L. The within-day precision, ranged from 3.0 to 7.9%, while the within-day accuracy ranged from -11.4 to 0.5%. The between day precision and accuracy were respectively less than 13.7 and -11.4%. The mean recovery was 75.7% for darunavir and 66.7% for methylclonazepam. This method provides a useful tool for therapeutic drug monitoring in HIV patients.

OBJECT The blood-brain barrier (BBB) limits the intracerebral penetration of drugs and brain tumor treatment efficacy. The effect of ultrasound-induced BBB opening on the intracerebral concentration of temozolomide (TMZ) and irinotecan (CPT-11) was assessed. METHODS This study was performed using 34 healthy New Zealand rabbits. Half had unilateral BBB opening, and half served as controls. Sonications were performed by pulsing a 1.05-MHz planar ultrasound transducer with a duty cycle of 2.5% and an in situ acoustic pressure level of 0.6 MPa after injection of a microbubble ultrasound contrast agent. Drugs were injected either 5 minutes before (ChemoPreUS) or 15 minutes after (ChemoPostUS) the ultrasound sonication. The plasma and intracerebral concentrations of both drugs were quantified using ultra-performance liquid chromatography. RESULTS The mean intracerebral tissue-to-plasma drug concentration ratio in the control hemispheres was 34% for TMZ and 2% for CPT-11. After BBB opening, these values increased by up to 21% for TMZ and up to 178% for CPT-11. Intracerebral concentrations of drugs were enhanced in regions where the BBB was opened compared with the contralateral hemisphere (p < 0.01 and p < 0.0001 for CPT-11, p = 0.02 and p = 0.03 for TMZ, in ChemoPreUS and ChemoPostUS, respectively) and compared with the control group (p < 0.001 and p < 0.0001 for CPT-11, p < 0.01 and p = 0.02 for TMZ, in ChemoPreUS and ChemoPostUS, respectively). The intracerebral distribution of drugs was heterogeneous, depending on the distance from the ultrasound source. CONCLUSIONS Ultrasound-induced opening of the BBB significantly enhances the intracerebral concentration of both TMZ and CPT-11 in rabbits.

Glioblastoma is both the most common and aggressive primary brain tumor in adults. Carboplatin chemotherapy has shown only modest efficacy in progressive high-grade gliomas. The limited clinical efficacy of carboplatin may be due to its low concentration in tissue when the drug is delivered intravenously. The aim of this study was to assess whether the tissue concentration of intravenously administered carboplatin could be enhanced by ultrasound-induced blood–brain disruption in a primate model. Carboplatin was administered intravenously for 60 min to a single primate following blood–brain barrier opening induced by an implantable ultrasound device. Blood and brain samples were collected after animal killing, which occurred 60 min after the end of carboplatin administration. Platinum quantification in ultrafiltrate plasma and brain samples was performed using inductively coupled plasma mass spectrometry. The brain concentration of platinum was highly enhanced (5.2×) in the 3.9 cm3 region sonicated by the US beam, with a higher concentration in more vascularized anatomical structures. At 5 and 10 mm from the US beam axis, platinum concentrations were slightly enhanced (2.2× and 1.3× respectively). This study demonstrates that BBB opening using an implantable ultrasound transducer enhances the brain distribution of carboplatin in a loco-regional manner. Such a treatment approach is of significant interest for the treatment of primary brain tumors and is under current evaluation in a phase 1 clinical trial (NCT02253212).

One of the main limitations to the efficacy of chemotherapy in the brain is the blood-brain barrier (BBB). Previous pre-clinical studies have demonstrated that disruption of the BBB using pulsed ultrasound in combination with an ultrasound microbubble contrast agent can significantly increase the concentration of chemotherapy agents in the brain. Our group has developed an implantable, MR compatible ultrasound device for temporarily disrupting the BBB. The safety of repeated disruption of the BBB using such a device was previously demonstrated in a long-term safety study in four non-human primates. The purpose of this work was to determine the safety and potential efficacy of temporarily disrupting the BBB in patients with recurrent glioblastoma before chemotherapy administration in a first-in-man clinical trial.

Glioblastoma (GBM), the most common primary brain tumor in adults, is usually rapidly fatal with median survival duration of only 15 months and a 3-year survival rate of