Use of a Sequential Strategy in Intelligibility Testing

1967 ◽  
Vol 42 (3) ◽  
pp. 609-612 ◽  
Author(s):  
H. Levitt ◽  
L. R. Rabiner
Keyword(s):  
2021 ◽  
Vol 39 (3_suppl) ◽  
pp. 324-324
Author(s):  
Ciro Celsa ◽  
Giuseppe Cabibbo ◽  
Marco Enea ◽  
Salvatore Battaglia ◽  
Giacomo Emanuele Maria Rizzo ◽  
...  

324 Background: Atezolizumab plus Bevacizumab represents the new best performing first-line approach for unresectable hepatocellular carcinoma (u-HCC). However, the best sequential strategy after every first-line failure (for progression or intolerance) remains elusive, and options for retreating patients failing Atezolizumab plus Bevacizumab with multi-kinase inhibitors (MKI) or immune checkpoint inhibitor (ICI) are yet undefined. Methods: We developed a Markov model to analyze simulated-Overall Survival (s-OS) of second-line ICIs or MKIs after first-line Atezolizumab plus Bevacizumab over a lifetime horizon. For first-line therapy, PFS of Atezolizumab plus Bevacizumab was extracted from Imbrave 150 trial and it was used as endpoint since it is not influenced by post-progression survival. For second-line retreatment, pooled OS of MKIs (Regorafenib and Cabozantinib), or ICIs (Nivolumab and Pembrolizumab) were adopted. Survival estimates for sequential settings considered the proportion of patients who did not receive second-line therapy due to death during first-line therapy. Individual patient survival data were extracted from PFS and OS Kaplan-Meier curves of RESORCE trial for Regorafenib, CELESTIAL trial for Cabozantinib, CheckMate-040 for Nivolumab and Keynote-240 for Pembrolizumab. Each reconstructed survival curve was inspected for accuracy and was compared with originally published curves. Results: First-line Atezolizumab plus Bevacizumab followed by second-line ICIs turned on from the model as the best sequential strategy (median s-OS 24 months; 95% Confidence Interval (CI) 23-26 months) and extends survival when compared Atezolizumab plus Bevacizumab followed by MKIs (median s-OS 20 months; 95% CI 19-21 months). Conclusions: To our knowledge and given the absence of adequately designed sequential RCTs, this is the first model to date which suggests, with a proper methodological approach, an accurate estimate of outcome of patients with u-HCC treated by sequential systemic therapies. In patients with u-HCC failing first-line treatment, modelling estimates of s-OS for each retreatment strategies may assist in choosing the most promising sequences in order to plan appropriate RCTs.


2011 ◽  
Vol 133 (9) ◽  
Author(s):  
Diane L. Peters ◽  
P. Y. Papalambros ◽  
A. G. Ulsoy

Optimal system design of “smart” products requires optimization of both the artifact and its controller. When the artifact and the controller designs are independent, the system solution is straightforward through sequential optimization. When the designs are coupled, combined simultaneous optimization can produce system-optimal results, but presents significant computational and organizational complexity. This paper presents a method that produces results comparable with those found with a simultaneous solution strategy, but with the simplicity of the sequential strategy. The artifact objective function is augmented by a control proxy function (CPF), representing the artifact’s ease of control. The key to successful use of this method is the selection of an appropriate CPF. Four theorems that govern the choice and evaluation of a CPF are given. Each theorem is illustrated using a simple mathematical example. Specific CPFs are then presented for particular problem formulations, and the method is applied to the optimal design and control of a micro-electrical mechanical system actuator.


2009 ◽  
Vol 36 (7) ◽  
pp. 895-900 ◽  
Author(s):  
Helen Treichel ◽  
Marcio Antonio Mazutti ◽  
Francisco Maugeri ◽  
Maria Isabel Rodrigues

Author(s):  
Huaxiong Li ◽  
Xianzhong Zhou ◽  
Bing Huang ◽  
Dun Liu
Keyword(s):  

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 189-189 ◽  
Author(s):  
Charlotte Pawlyn ◽  
Faith E Davies ◽  
David A Cairns ◽  
Corinne Collett ◽  
Anna Chalmers ◽  
...  

Abstract Background: Maximising response in myeloma (MM) patients with effective induction regimens prior to autologous stem cell transplant (ASCT) improves progression-free and overall survival. Triplet regimens combining an immunomodulatory agent (IMiD) and/or proteasome inhibitor (PI) are standard of care, however a more personalised approach is achieved by sequential triplet combinations based on an individual's response. Alternatively, quadruplet regimens may be more effective and new generation PIs such as carfilzomib, with less off-target activity, provide the opportunity to investigate this whilst minimising the risk of increased toxicity. The UK NCRI Myeloma XI trial is a large, phase III study aiming to answer these questions in transplant eligible (TE) patients comparing the quadruplet carfilzomib, cyclophosphamide, lenalidomide and dexamethasone to the sequential strategy of triplet IMiD combinations (with thalidomide or lenalidomide) followed by additional PI triplet therapy for those with a suboptimal response (<VGPR) prior to ASCT. Methods: In 2013, the TE pathway was amended to include KCRD: carfilzomib 36mg/m2 IV d1-2,8-9,15-16 (20mg/m2 #1d1-2), cyclophosphamide (cyclo) 500mg PO d1,8, lenalidomide (len) 25mg PO d1-21, dexamethasone (dex) 40mg PO d1-4,8-9,15-16). Patients are randomised to this up-front quadruplet or the sequential strategy of CRD: cyclo 500mg PO d1,8, len 25mg PO d1-21 PO daily, dex 40mg PO d1-4, 12-15 or CTD: cyclo 500mg PO d1,8,15 thalidomide 100-200mg PO daily, dex 40mg PO d1-4,12-15 given to max. response - patients with VGPR/CR proceed straight to ASCT, PR/MR are randomised to sequential CVD: cyclo 500mg d1,8,15, bortezomib 1.3mg/m2 IV/SC d1,4,8,11, dex 20mg PO d1,2,4,5,8,9,11,12 or nothing and SD/PD all receive sequential CVD. All treatments are given to max. response prior to ASCT, after which there is a maintenance randomisation. Patients: 1512 patients entered the TE pathway prior to amendment (756 CRD, 756 CTD). Of these, 201 patients with a suboptimal initial response went on to receive CVD, 142 following randomisation (initial response PR/MR) and 59 with NC/PD. 788 (of target n=1036) patients have been randomised post-amendment to date (394 KCRD, 197 CRD, 197 CTD). Results: TE patients receiving treatment prior to the amendment had response rates ≥VGPR: CRD 58% vs CTD 52%. For patients receiving the sequential triplet CVD due to a suboptimal response this was upgraded to ≥VGPR in 49% of those with initial MR/PR, 27% with NC/PD. This suggests the overall ≥VGPR rate to this treatment approach prior to ASCT would be approx. 75%. This now needs to be compared to the alternative approach of an upfront quadruplet. Comparing patients contemporaneously randomised to initial induction the patients receiving KCRD have completed a median 4 cycles (range 1-7), CRD 5 (range 1-10) and CTD 6 (range 1-9). Dose modifications have been required in 62% of patients receiving KCRD (56% to carfilzomib, 42% to lenalidomide) 44% CRD (40% to lenalidomide) and 65% CTD (59% to thalidomide). Data for study drug related toxicity in patients who have completed at least one cycle of initial induction are shown in table 1. Serious adverse events suspected to be due to trial medications have occurred in 37% on KCRD, 32% CRD and 35% CTD. Updated toxicity and preliminary response analysis on 23/09/15 will be presented at the meeting. This will include a response comparison at the end of initial induction regimen i.e. KCRD vs CRD vs CTD for an anticipated 700 contemporaneous patients who will have completed treatment. Updated response to the sequencing approach (with 250 patients having received sequential CVD) will also be presented and compared. Conclusions: In our study KCRD, an outpatient delivered 4-drug regimen combining second generation IMiD and PI drugs, is well-tolerated in TE NDMM patients, comparable to 3-drug regimens. Data will be presented at the meeting to compare the response rates achieved with the different regimens and treatment approaches. On behalf of the NCRI Haemato-oncology CSG Table 1. Comparative toxicities KCRD n=261 CRD n=143 CTD n=142 % (no. of patients) Peripheral neuropathy Sensory Gr II-IV 1.9 (5) 1.4 (2) 8.5 (12) Motor Gr II-IV 3.1 (8) 1 (1) 5.6 (8) VTE all grades 4.2 (11) 4.9 (7) 5.6 (8) Anaemia Gr III-IV 9.2 (24) 4.2 (6) 5.6 (8) Neutropenia Gr III-IV 14.9 (39) 16.1 (22) 13.3 (19) Thrombocytopenia Gr III-IV 8.4 (22) 1.4 (2) 1.4 (2) Infusion reaction Gr III-IV 0.4 (1) - - Disclosures Pawlyn: Celgene: Honoraria, Other: Travel support; The Institute of Cancer Research: Employment. Off Label Use: Carfilzomib as induction treatment for myeloma Lenalidomide and vorinostat as maintenance treatments for myeloma. Davies:University of Arkansas for Medical Sciences: Employment; Celgene: Honoraria; Onyx-Amgen: Honoraria; Takeda-Milenium: Honoraria. Jones:Celgene: Other: Travel support, Research Funding. Kaiser:Janssen: Honoraria; Chugai: Consultancy; Amgen: Consultancy, Honoraria; BristolMyerSquibb: Consultancy; Celgene: Consultancy, Honoraria, Research Funding. Jenner:Takeda: Honoraria; Amgen: Honoraria. Cook:Jazz Pharma: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau; Chugai: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau. Russell:Therakos: Other: shares. Owen:Celgene: Honoraria, Research Funding; Janssen: Honoraria. Gregory:Janssen: Honoraria; Celgene: Honoraria. Jackson:Celgene: Honoraria; Amgen: Honoraria; Takeda: Honoraria. Morgan:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda-Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; CancerNet: Honoraria; Weisman Institute: Honoraria; MMRF: Honoraria; MMRF: Honoraria; University of Arkansas for Medical Sciences: Employment; Weisman Institute: Honoraria; CancerNet: Honoraria.


2012 ◽  
Vol 2012 ◽  
pp. 1-5
Author(s):  
Maria Rambla-Alegre

Retention in micellar liquid chromatography is highly reproducible and can be modelled using empirical or mechanistic models with great accuracy to predict the retention changes when the mobile phase composition varies (surfactant and organic solvent concentrations), thus facilitating the optimisation of separation conditions. In addition, the different equilibria inside the column among the solute, the mobile phase, and the modified stationary phase by monomers of surfactant have been exhaustively studied. In a sequential strategy, the retention of the solutes is not known a priori, and each set of mobile phases is designed by taking into account the retention observed with previous eluents. By contrast, in an interpretative strategy, the experiments are designed before the optimization process and used to fit a model that will allow the prediction of the retention of each solute. This strategy is more efficient and reliable. The sequential strategy will be inadequate when several local and/or secondary maxima exist, as frequently occurs in chromatography, and may not give the best maximum, that is to say, the optimum. More often than not, the complexity of the mixtures of compounds studied and the relevant modification of their chromatographic behaviour when changing the mobile phase composition requires the use of computer-assisted simulations in MLC to follow the modifications in the chromatograms in detail. These simulations can be done with sound reliability thanks to the use of chemometrics tools.


Sign in / Sign up

Export Citation Format

Share Document