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1.
Objective: In the absence of head-to-head trials, this study indirectly compared progression free survival (PFS) and overall survival (OS) between ceritinib and crizotinib among patients with previously untreated advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC).

Methods: A matching-adjusted indirect comparison method was implemented to adjust for cross-trial differences in patient characteristics between ASCEND-4 and PROFILE 1014 trials. Patient-level data from ASCEND-4 and published summary data from PROFILE 1014 were used. Patients in ASCEND-4 were reweighted to match average baseline characteristics (i.e. age, sex, race, tumor histology, ECOG score, smoking status, extent of disease, and presence of brain metastases) reported for PROFILE 1014 patients using propensity score weighting. PFS and OS were then compared between balanced populations.

Results: ASCEND-4 included more current smokers (8.0% vs 4.4%) and fewer patients under the age of 65 years (78.5% vs 84.0%) compared to PROFILE 1014. After matching, these and all other patient characteristics were balanced between the two trial populations. Compared to crizotinib, ceritinib was associated with a significantly longer PFS (hazard ratio [95% confidence interval] (HR [CI])?=?0.64 [0.47–0.87]; median PFS: 25.2 vs 10.8 months, log-rank p-value?=?0.003). OS did not differ significantly, with a HR of 0.82 [0.54–1.27] for ceritinib compared to crizotinib.

Conclusions: In the adjusted indirect comparison with external controls, the second generation ALK inhibitor, ceritinib, was associated with a significantly prolonged PFS compared to crizotinib as first-line treatment for ALK-positive NSCLC.  相似文献   

2.
Sexually transmitted infections (STIs) remain major public health problems globally. Appropriate laboratory diagnosis of STIs is rare in Ukraine. We investigated the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) using the US FDA‐approved Aptima Combo 2 and Aptima TV assays and compared the results with the conventional routine diagnostic tests (CDTs) in Ukraine. Urogenital swabs from consecutive mostly symptomatic females (n = 296) and males (n = 159) were examined. The prevalences were as follows: 10% (n = 47) of TV, 5.3% (n = 24) of CT and 1.5% (n = 7) of NG. The specificity of some CDTs was high, for example, 100% for NG culture, TV IgG ELISA, CT IgM ELISA and CT microscopy, but lower for other CDTs, that is, from 44% to 99.8%. The sensitivity of all CDTs was suboptimal, that is, 71% (n = 5) for NG microscopy, 57% (n = 4) for NG culture, 53% (n = 8) for CT IgG ELISA, 33% (n = 1) for TV IgG ELISA, 28% (n = 13) for TV microscopy, 25% (n = 1) for CT IgA ELISA, 20% (n = 3) for CT IgM ELISA and 0% (n = 0) for CT microscopy. The prevalences of particularly TV and CT were high, but substantial also for NG, in Ternopil, Ukraine. The sensitivities of all CDTs were low, and widespread implementation of validated, quality‐assured and cost‐effective molecular diagnostic STI tests in Ukraine is imperative.  相似文献   
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Bacterial lipopolysaccharide (LPS) activates the immune system and promotes inflammation via Toll-like receptor (TLR) 4, which regulates the synthesis and release of tumor necrosis factor (TNF)-alpha and other inflammatory cytokines. Previous studies have shown that the nucleoside adenosine suppresses LPS-stimulated TNF-alpha release in human UB939 macrophages by activating an adenosine A(3) receptor (A(3)AR) subtype on these cells. In this study, we examined the mechanism(s) underlying A(3)AR-dependent inhibition of TNF-alpha release in a mouse (RAW 264.7) cell line. Treatment of RAW 264.7 cells with LPS (3 mug/ml) increased TNF-alpha release, which was reduced in a dose-dependent manner by adenosine analogs N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) and R-phenylisopropyladenosine and reversed by selective A(3)AR blockade. The increase in TNF-alpha release was preceded by an increase in intracellular Ca(2+) levels. Inhibition of intracellular Ca(2+) release by IB-MECA, a selective agonist of the A(3)AR, or with BAPTA-AM, an intracellular Ca(2+) chelator, reduced LPS-stimulated TNF-alpha release. Activation of the A(3)AR or inhibition of intracellular Ca(2+) release also reduced LPS-stimulated nuclear factor-kappaB (NF-kappaB) activation and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. Similar inhibition by A(3)AR was observed for LPS-stimulated inducible nitric-oxide synthase. These data support the contention that inhibition of LPS-stimulated release of inflammatory molecules, such as TNF-alpha and NO via the A(3)AR, involves suppression of intracellular Ca(2+)signaling, leading to suppression of NF-kappaB and ERK1/2 pathways.  相似文献   
7.

Introduction

Crizotinib is recommended as first-line therapy for ALK-positive non-small cell lung cancer (NSCLC), but within a year of treatment initiation many patients develop resistance. With the recent approval of second-generation ALK inhibitors, this study assessed how physicians monitor for and diagnose progression and how they alter treatment following progression on crizotinib.

Methods

A panel of oncologists from the United States were surveyed regarding their monitoring practices and criteria for diagnosing progression on crizotinib. The physicians also retrospectively provided data (March–June 2016) from the medical charts of their adult patients with locally advanced or metastatic ALK-positive NSCLC who progressed on crizotinib after the approval (April 2014) of the first second-generation ALK inhibitor, ceritinib.

Results

A total of 28 physicians responded to the survey. Data was abstracted on 74 patients. In the physician survey, most physicians (71%) reported monitoring for radiographic progression every 3–4 months. When new lesions were detected, physician response varied. Following a symptomatic isolated lesion, most physicians (75%) would add local therapy and resume crizotinib. Following multiple symptomatic lesions, 96% and 64% of physicians would switch to a new therapy depending on whether the lesions were extracranial or isolated to the brain, respectively. For the patient cohort, physician-defined progression on crizotinib was diagnosed after a median of 10 months, and within 30 days of diagnosis, 86% of patients discontinued crizotinib. Among all patients who discontinued crizotinib, 77% switched to ceritinib, 14% to chemotherapy, and 1% to alectinib. The remaining 7% did not receive additional systemic antineoplastic therapy.

Conclusion

The findings from this physician survey and retrospective chart review study suggest that physician response to the development of new lesions in crizotinib-treated ALK-positive NSCLC patients varies with location and extent of the lesions. Once patients were considered to have progressed, most of them were immediately switched to ceritinib.

Funding

Novartis Pharmaceuticals Corporation.
  相似文献   
8.
In search for potential synergistic antimicrobial combinations against Staphylococcus aureus isolates, which display heterogeneous resistance to vancomycin, we evaluated the activities of 21 various combinations involving ampicillin/sulbactam, daptomycin, gentamicin, linezolid, quinupristin/dalfopristin, rifampin, and vancomycin by Etest and time-kill methods. A number of combinations demonstrated either synergistic or additive effects against hGISA SA118 and GISA SA179. Agreement between the Etest and time-kill methods for detecting antimicrobial synergy ranged from 66.6% to 71.4%. The Etest method appears promising, and further investigations are warranted.  相似文献   
9.
Clinical trials with daptomycin were halted in December 1990 because of treatment failures including two resistant Staphylococcus aureus strains. High protein binding of daptomycin (> 90%) and the lower-than-expected concentrations in serum with the dosage regimen of 3 mg/kg of body weight every 12 h may have contributed to these failures. To evaluate the effect that higher concentrations would have on bactericidal activity measured by time-kill curves, peak and trough concentrations were estimated for dosage regimens of 3, 5, and 10 mg/kg every 12 h. MICs, MBCs, and killing curves for daptomycin and vancomycin were performed by using the estimated concentrations with four S. aureus strains obtained from patients who failed daptomycin therapy for endocarditis. MICs and MBCs of daptomycin demonstrated a greater inoculum effect than those of vancomycin; MICs and MBCs of daptomycin increased three- to fourfold, but those of vancomycin increased only one- to twofold when the inoculum was increased from 5 x 10(5) to 5 x 10(7) CFU/ml. No pH-dependent effect on MICs or MBCs was seen. Strenuous experimental conditions were chosen: high inoculums (5 x 10(7) CFU/ml), extremes of pH (6.4, 7.4, and 8), and stationary and exponentially growing organisms; and all experiments completed in the presence of pooled human serum. Daptomycin exhibited concentration-dependent killing and statistically faster kill rates than vancomycin against stationary- or exponential-growth-phase organisms. A pH-dependent decrease in activity with daptomycin was also demonstrated. Daptomycin and vancomycin produced higher kill rates against exponentially growing organisms. A pH-dependent decrease in activity with daptomycin was also demonstrated. Daptomycin and vancomycin produced higher kill rates against exponentially growing organisms. The results indicate that the use of higher dosage regimens with compounds similar to daptomycin may be capable of overcoming the effects of pH, high inoculum, and protein binding.  相似文献   
10.
Use of combinations of antimicrobials that together achieve synergistic activities against targeted microorganisms is one potential strategy for overcoming bacterial resistance. As the incidence of infections caused by multidrug-resistant staphylococci and enterococci increases, the importance of devising additional synergistic drug combinations for these bacteria is magnified. We evaluated a number of antimicrobial combinations, with a focus on quinupristin-dalfopristin (Q-D), cefepime, and linezolid, using a previously described in vitro pharmacodynamic model. The combination of Q-D with either linezolid or vancomycin, as well as the combination of cefepime-vancomycin, resulted in enhanced killing (> or =2-log(10) increase in killing versus the most-active single agent) against methicillin-resistant Staphylococcus aureus (MRSA) 494. An improved effect (<2 log(10) kill increase in kill) against MRSA 494 was noted for cefepime plus either Q-D or linezolid, as well as linezolid-vancomycin. Similar relationships were observed for a methicillin-susceptible S. aureus isolate (isolate 1199). Against methicillin-resistant S. epidermidis R444, enhanced killing was achieved with the combination of cefepime-linezolid, while improvement was noted for vancomycin with either cefepime or linezolid. The combination of cefepime and vancomycin also achieved enhanced killing against a glycopeptide-intermediate-susceptible S. aureus isolate (isolate 992). The combination of linezolid and doxycycline achieved an enhanced effect against vancomycin-resistant Enterococcus faecalis (VREFc) and E. faecium. Q-D plus ampicillin or linezolid resulted in similar enhancement of activity against the VREFc isolate. The results of this study suggest a number of novel antimicrobial combinations that may be useful against staphylococci and enterococci. Combination regimens including cefepime, Q-D, and/or linezolid warrant further investigation for the treatment of refractive infections due to multidrug-resistant gram-positive pathogens.  相似文献   
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