Designing studies to find early signals of efficacy.

abstract：:A statistic, W, for measuring change from baseline is developed. Its distribution is found. Simulations using W and analysis of covariance (ANCOVA) are run and the results are compared. W is found to be less powerful than ANCOVA, yet is not seen to suffer some of the ill effects to which ANCOVA can fall prey, namely b...

journal_title：Journal of biopharmaceutical statistics

authors： Donahue RM

更新日期：1997-05-01 00:00:00

abstract：:Pharmacokinetic studies of drug and metabolite concentrations in the blood are usually conducted as crossover trials, especially in phases I and II. A longitudinal series of measurements is collected on each subject within each period. However, much of the dependence among such observations, within and between periods...

journal_title：Journal of biopharmaceutical statistics

authors： Lindsey JK,Wang J,Byrom WD,Jones B

更新日期：1999-08-01 00:00:00

abstract：:Recently, two CPMP Points to Consider, one on adjustment for baseline covariates and the other on multiplicity issues in clinical trials, have included recommendations on the use of subgroup analysis for regulatory purposes. However, despite their regular use and regulatory attention, the validity and nature of subgro...

journal_title：Journal of biopharmaceutical statistics

authors： Grouin JM,Coste M,Lewis J

更新日期：2005-01-01 00:00:00

abstract：:The design of a three-arm trial including the experimental treatment, an active reference treatment, and a placebo is recommended as a useful approach to the assessment of noninferiority of the experimental treatment. The inclusion of the placebo arm enables the assessment of assay sensitivity and internal validation,...

journal_title：Journal of biopharmaceutical statistics

authors： Hida E,Tango T

更新日期：2013-01-01 00:00:00

abstract：:In the early stages of traditional drug development, the frequency of dosing (e.g., QD, BID, etc.) is typically determined by the pharmacokinetic properties of a compound. After an appropriate dose frequency is chosen, the magnitude of dose is then evaluated via parallel-group dose-response trials. For some drugs, how...

journal_title：Journal of biopharmaceutical statistics

authors： Hafner KB,Ruberg SJ

更新日期：1996-07-01 00:00:00

abstract：:As more biologic products are going off patent protection, the development of follow-on biologic products (also known as biosimilars) has gained much attention from both the biotechnology industry and regulatory agencies. Unlike small molecules, the development of biologic products is not only more complicated but als...

journal_title：Journal of biopharmaceutical statistics

authors： Zhang N,Yang J,Chow SC,Chi E

更新日期：2014-01-01 00:00:00

abstract：:There is often a need to determine parallelism or linearity between pairs of dose-response data sets for various biological applications. This article describes a technique based on a modification of the well-known extra-sum-of-squares principle of statistical regression. The standard extra-sum-of-squares method uses ...

journal_title：Journal of biopharmaceutical statistics

authors： Gottschalk PG,Dunn JR

更新日期：2005-01-01 00:00:00

abstract：:When marketed lots of pharmaceutical products produce a number of out-of-specification (OOS) samples, it can be very disruptive. In some cases such lots must be recalled, at substantial expense. We present a model of the probability of OOS samples and show quantitatively how this probability depends on the underlying ...

journal_title：Journal of biopharmaceutical statistics

authors： Fairweather WR

更新日期：2003-08-01 00:00:00

abstract：:For approval of generic drugs, the U.S. Food and Drug Administration (FDA) requires the evidence of bioequivalence in average bioavailability be provided. This is based on the Fundmental Bioequivalence Assumption from FDA that if two drug products are shown to be bioequivalent, it is assumed that they are therapeutica...

journal_title：Journal of biopharmaceutical statistics

authors： Lu Y,Zhang ZZ,Chow SC

更新日期：2014-01-01 00:00:00

abstract：:A main challenge in molecular diagnostic research is to accurately evaluate the performance of a new nucleic acid amplification test when the reference standard is imperfect. Several approaches, such as discrepant analysis, composite reference standard (CRS) method, or latent class analysis (LCA), are commonly applied...

journal_title：Journal of biopharmaceutical statistics

authors： Tang S,Hemyari P,Canchola JA,Duncan J

更新日期：2018-01-01 00:00:00

abstract：:Historical control trials (HCTs) are frequently conducted to compare an experimental treatment with a control treatment from a previous study, when they are applicable and favored over a randomized clinical trial (RCT) due to feasibility, ethics and cost concerns. Makuch and Simon developed a sample size formula for h...

journal_title：Journal of biopharmaceutical statistics

authors： Zhu H,Zhang S,Ahn C

更新日期：2016-01-01 00:00:00

abstract：:Randomized controlled clinical trials often use a composite endpoint as a primary endpoint especially when treatment effects or frequency of individual components of the composite are likely to be small and combining them makes clinical sense for the disease under study. An advantage of the composite endpoint is that,...

journal_title：Journal of biopharmaceutical statistics

authors： Huque MF,Alosh M,Bhore R

更新日期：2011-07-01 00:00:00

abstract：:In a clinical dose finding study with active control a new drug with several dose levels is compared with an active comparator drug. The main focus of such studies often lies on the estimation of a target dose that leads to the same efficacy as the control. This article investigates the finite sample properties of the...

journal_title：Journal of biopharmaceutical statistics

authors： Helms HJ,Benda N,Friede T

更新日期：2015-01-01 00:00:00

abstract：:The United States Pharmacopeia (USP) content uniformity sampling acceptance plan consisting of a two-stage sampling plan with criteria on sample mean and number of out-of-range tablets is the standard for compendium. It is, however, often used mistakenly for lot quality assurance. In comparison to the Japan Phamacopei...

journal_title：Journal of biopharmaceutical statistics

authors： Tsong Y,Shen M

更新日期：2007-01-01 00:00:00

abstract：:A test and a reference analytical method are usually compared for agreement based on paired data obtained from several independent subjects. Bias between two methods can be classified as constant and proportional. In this article, we provide an approach for maximum likelihood estimation of total bias between two metho...

journal_title：Journal of biopharmaceutical statistics

authors： Magari RT

更新日期：2004-11-01 00:00:00

abstract：:Assessment of quality of life (QOL) in clinical trials becomes a challenging task from the viewpoint of clinical biostatistics. The responses of the items for measuring QOL indices usually vary widely from patient to patient and from time to time. Measurement errors might be present in the responses of the items, and ...

journal_title：Journal of biopharmaceutical statistics

authors： Siddiqui O,Ali MW

更新日期：1999-11-01 00:00:00

abstract：:During preclinical drug development, the immune system is specifically evaluated after prolonged treatment with drug candidates, because the immune system may be an important target system. The response of antibodies against a T-cell-dependent antigen is recommenced by the FDA and EMEA for the evaluation of immunosupp...

journal_title：Journal of biopharmaceutical statistics

authors： Shkedy Z,Straetemans R,Molenberghs G,Desmidt M,Vinken P,Goeminne N,Coussement W,Van Den Poel B,Bijnens L

更新日期：2005-01-01 00:00:00

abstract：:Multipopulation tailoring trials provide a trial design option that supports the realization of tailored therapeutics or personalized medicine. Several recent publications have focused on statistical and clinical considerations that arise in these trials that are designed to study the overall treatment effect in a pop...

journal_title：Journal of biopharmaceutical statistics

authors： Millen BA,Dmitrienko A,Song G

更新日期：2014-01-01 00:00:00

abstract：:In method comparison and reliability studies, it is often important to assess agreement between multiple measurements made by different methods, devices, laboratories, observers, or instruments. For continuous data, the concordance correlation coefficient (CCC) is a popular index for assessing agreement between multip...

journal_title：Journal of biopharmaceutical statistics

authors： Barnhart HX,Lokhnygina Y,Kosinski AS,Haber M

更新日期：2007-01-01 00:00:00

abstract：:Administration of biological therapeutics can generate undesirable immune responses that may induce anti-drug antibodies (ADAs). Immunogenicity can negatively affect patients, ranging from mild reactive effect to hypersensitivity reactions or even serious autoimmune diseases. Assessment of immunogenicity is critical a...

journal_title：Journal of biopharmaceutical statistics

authors： Zhang J,Yu B,Zhang L,Roskos L,Richman L,Yang H

更新日期：2015-01-01 00:00:00

abstract：:In the era of precision medicine, drugs are increasingly developed to target subgroups of patients with certain biomarkers. In large all-comer trials using a biomarker stratified design, the cost of treating and following patients for clinical outcomes may be prohibitive. With a fixed number of randomized patients, th...

journal_title：Journal of biopharmaceutical statistics

authors： Wang X,Zhou J,Wang T,George SL

更新日期：2018-01-01 00:00:00

abstract：:A framework is proposed for making quality predictions in situations for which only systematically inaccurate data are available. The predictions are based on the systematically inaccurate data, complete data from similar situations, and expert knowledge. The proposed predictive model is well suited to functional data...

journal_title：Journal of biopharmaceutical statistics

authors： Haaland B,Chiang AY

更新日期：2014-01-01 00:00:00

abstract：:The aim of this article is to propose a multilevel combined model for repeated, hierarchical, and overdispersed time-to-event outcomes, extending the so-called combined model proposed by Molenberghs et al. (2010), and using three different estimation strategies: full likelihood, pseudo-likelihood, and Bayesian estimat...

journal_title：Journal of biopharmaceutical statistics

authors： Efendi A,Molenberghs G

更新日期：2013-01-01 00:00:00

abstract：:Sample size calculation based on normal approximations is often associated with the loss of statistical power for a single-arm trial with a time-to-event endpoint. Recently, Wu (2015) derived the exact variance for the one-sample log-rank test under the alternative and showed that a single-arm one-stage study based on...

journal_title：Journal of biopharmaceutical statistics

authors： Shan G

更新日期：2020-09-02 00:00:00

abstract：:Using multistage adaptive group sequential test designs, the investigator may perform data-driven changes in the design during the course of the trial without inflation of the Type I error rate. This is possible, for example, through the use of the inverse normal method of combining the p-values from the separate stag...

journal_title：Journal of biopharmaceutical statistics

authors： Wassmer G

更新日期：2003-11-01 00:00:00

abstract：:Recently, a design was proposed for the Simultaneous Global Drug Development Program (SGDDP) to assess the impact of ethnic factors on the effect of a new treatment for a targeted ethnic (TE) population. It used weighted Z tests to combine the information collected from the TE and non-TE (NTE) subgroups in the SGDDP b...

journal_title：Journal of biopharmaceutical statistics

authors： Liu K,Yuan Z,Chen G,Huang Q,Wenrich J

更新日期：2015-01-01 00:00:00

abstract：:When performing a pivotal clinical trial, it may be of interest to assess the probability of success (PoS) of that trial. Initially evaluated when the trial is designed, PoS can be updated as the trial progresses and new information about the drug effect becomes available. Such information can be external to the trial...

journal_title：Journal of biopharmaceutical statistics

authors： Rufibach K,Jordan P,Abt M

更新日期：2016-01-01 00:00:00

abstract：:Dichotomizing a continuous biomarker is a common practice in medical research. Various methods exist in the literature for dichotomizing continuous biomarkers. The most widely adopted minimum p-value approach uses a sequence of test statistics for all possible dichotomizations of a continuous biomarker, and it chooses...

journal_title：Journal of biopharmaceutical statistics

authors： Su M,Fang L,Su Z

更新日期：2013-05-01 00:00:00

abstract：:Group sequential methods to allow the possibility of early termination of a trial due to sufficiently convincing results are a standard in therapeutic clinical trials but have been little considered in bioequivalence trials. We investigate the statistical properties of one group sequential approach to bioequivalence t...

journal_title：Journal of biopharmaceutical statistics

authors： Hauck WW,Preston PE,Bois FY

更新日期：1997-03-01 00:00:00

abstract：:In this article, we show how to estimate a transition period for the evolvement of drug resistance to antiretroviral (ARV) drug or other related treatments in the framework of developing a Bayesian method for jointly analyzing time-to-event and longitudinal data. For HIV/AIDS longitudinal data, developmental trajector...

journal_title：Journal of biopharmaceutical statistics

authors： Dagne GA

更新日期：2018-01-01 00:00:00