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In the U.S. Food and Drug Administration (FDA) guidelines for stability testing of new drug products, both bracketing and matrixing designs were suggested as the statistical designs. More recently, they have increasing attention from pharmaceutical companies, because both designs reduce the cost of stability studies. The purpose of this paper is to investigate both designs in terms of the power of detection of significant difference between slopes, and use the mean square error to evaluate the precision of estimated drug shelf life. Additionally, the distributions of both designs are compared by using 1000 simulations.

This paper provides a brief history and an overview of the regulatory process for drug approval in the United States through illustrations of Investigational New Drug (INDs) Applications and New Drug Applications (NDAs). For INDs, the regulatory requirements for a well-designed protocol, the role and responsibility of institutional review boards, and the applicability of treatment INDs are discussed. For NDAs, issues regarding the application of expanded access, the submission of abbreviated NDAs for a generic drug, the submission of supplemental NDAs for labeling changes, and the role and responsibility of advisory committees are addressed.

In recent years, the concept of quality by design in (global) pharmaceutical development has received much attention. The purpose is to ensure that the compound under investigation will possess good drug characteristics such as identity, strength, purity, quality, safety, efficacy and stability before and post approval. A pharmaceutical development process consists of non-clinical (e.g., assay/process validation and stability testing), pre-clinical (e.g., animal and bioavailability/bioequivalence studies), and clinical (e.g., phases 1-3 clinical trials) development. In this article, various statistical designs that are commonly considered for achieving desired good drug characteristics as described in the United States Pharmacopeia and National Formulary (USP/NF) at various stages of non-clinical, pre-clinical, and clinical development are reviewed. In addition, the possible use of innovative adaptive clinical trial designs that may lead to (i) the identification of any signals, trends/patterns, and optimal clinical benefits of a test treatment under investigation, and (ii) increase the probability of success of the development process with limited resources available are discussed.

For approval of a drug product, the United States Food and Drug Administration (FDA) requires that substantial evidence of the effectiveness and safety of the drug product be provided through the conduct of two adequate, well-controlled clinical trials. To assist the sponsors in preparation of final clinical reports for regulatory submission and review, the FDA and other regulatory agencies and conferences such as the International Conference on Harmonization (ICH) have developed guidelines for the format and content of a clinical report. The FDA and ICH guidelines require that the following statistical issues be addressed in the final clinical report: I. Baseline comparability, 2. Adjustments for covariates, 3. Dropouts or missing values, 4. Interim analyses and data monitoring, 5. Multicenter studies, 6. Multiplicity, 7. Intention-to-treat subset versus efficacy subset, 8. Active control trials, and 9. Subgroup analyses. This paper provides an overview of these statistical issues. In addition, statistical justification for these issues is also addressed.

Vitamin D supplementation is recommended for women with osteoporosis. In the FOCUS-D trial comparing the combination tablet alendronate plus vitamin D3 5,600 IU (ALN/D) with standard care (SC) prescribed by patients’ personal physicians, ALN/D was more effective in improving serum 25(OH)D and bone turnover markers by 6 months and increasing spine and hip bone mineral density (BMD) after 1 year than SC. This post hoc analysis examined the relationship between BMD gain and 25(OH)D in women in SC receiving alendronate (SC/ALN, n = 134, 52 % of the SC group) and in the ALN/D group (n = 257). At baseline, participants were of mean age 73 years and 72 % were Caucasian, with a mean 25(OH)D of 14.9 ng/mL. In the SC/ALN group, most received vitamin D, although intake of vitamin D varied extensively (51 % received

The issues and opportunities of adaptive designs are discussed. Starting with the definitions of an adaptive design, its validity and integrity are discussed. The three key components of an adaptive design, i.e., Type I error control, p-value adjustment, and unbiased estimation and confidence interval are addressed. Various seamless designs are investigated. Recommendations are made in the following aspects: study planning, trial monitoring, analysis and reporting, trial simulation, and regulatory perspectives.

In recent years, the use of adaptive methods in clinical development based on accrued data has become very popular due to its flexibility in modifying trial procedures and/or statistical procedures of on-going clinical trials. However, it is a concern that the actual patient population after the modifications could deviate from the originally targeted patient population. Major modifications of trial procedures and/or statistical procedures of on-going trials may result in a totally different trial, which is unable to address the scientific/medical questions that the trial intends to answer.

This open-label, multicenter study evaluated the efficacy, safety, and cycle control of Yasmin, a new low-dose, monophasic oral contraceptive containing the unique progestogen drospirenone (DRSP) 3 mg and ethinyl estradiol (EE) 30 microg. DRSP is a synthetic progestogen that has antiandrogenic and antimineralocorticoid effects. In this study, 326 women were evaluated and 220 (67%) completed all 13 treatment cycles. The corrected Pearl Index was 0. 407. Of the 151 subjects who experienced intermenstrual bleeding at any time during the study, the majority (64%) had bleeding during only one or two pill cycles. Breakthrough bleeding without spotting occurred in 1% of all cycles, spotting without breakthrough bleeding in 9.3% of all cycles, and breakthrough bleeding with spotting in 3% of all cycles. Amenorrhea was observed in 3% of all cycles. In all, 20 subjects (6%) discontinued participation in the study because of adverse events. No serious adverse events related to the study drug were reported. No clinically significant changes in weight, blood pressure, or lipids were reported. The impact of the new progestogen DRSP on the women's self-perception of menstrual health was also evaluated. Subjects reported that symptoms of water retention, negative affect, and increased appetite significantly improved at cycle 6 from baseline. This study demonstrates that Yasmin is an effective oral contraceptive that is safe and well tolerated.