Clinical trial is a research performed in human volunteers to judge the safety and efficacy of the investigational product. It determines whether the new drug or treatment will work on a disease or will potentially be beneficial to the patients or not.

There are several types of Clinical Trial and they are-
->Treatment trials- it tests experimental treatments, new combinations of drugs, or new approaches to surgery or radiation therapy.

->Prevention trials- it looks for better ways to prevent disease in people who have never had the disease or to prevent a disease from returning. These approaches may include medicines, vitamins, vaccines, minerals, or lifestyle changes.

->Diagnostic trials- these are conducted to find better tests or procedures for diagnosing a particular disease or condition.

->Screening trials- it tests the best way to detect certain diseases or health conditions.

->Quality of Life trials (or Supportive Care trials)-it explores different ways to improve comfort and the quality of life for individuals with a chronic illness.

Different phases of Clinical Trial include the following phases-
Phase I- the researchers test a experimental drug or treatment in a small group of people (20-80) for the first time to evaluate its safety, determine a safe dosage range and identify its side effect. This is specifically performed on the healthy volunteers except for some crucial diseases, like, cancer, AIDS, leukemia, etc.

Phase II- the experimental study drug or treatment is given to a larger group of people (100-300) to see its effectiveness and to further evaluate its safety.

Phase III- the experimental study drug or treatment is given to large groups of people (1,000-3,000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the experimental drug or treatment to be used safely.

Phase IV-it is basically the post marketing studies which gives the additional information including the drug's risks, benefits, etc. Before entering into this trial, FDA approval is essential.

SAS (Statistical Analysis Software) is a robust tool for reporting and analysis. It is available in various platforms and can be easily used to produce highly customized reports. Mr. Gim Goodknight launched this software in the year 1976 for the statistical analysis work. This is basically used to access the data in different software, manipulation of the data, and extraction of clinical data from various sources, analysis and compilation of the data. This tool is robust in dealing with the clinical data. This tool is used to perform edit checks, cross-form edit checks, validation reports, summary reports and transfer of files per sponsor specifications, company specifications and CDISC standards. The present version of SAS being used is 9.3.

Statistical Analysis Plan (SAP) is prepared by the biostatistician who summarizes the protocol from an analysis point of view including the study population definitions, data definitions, and also statistical analyses to be performed. It also provides the details about the statistical procedure to be performed for primary and secondary endpoints and the information about the tables, graphs and listings to be generated as a part of the Clinical Study Report.

Role of a SAS Programmer is data analysis, reporting of the analysed datasets, data extraction, edit checks, validation, and submission work.

Clinical Data Interchange Standards Consortium is a non-profit organization utilised to develop industry standards to support acquisition, exchange, submission and archiving of clinical trials data for medical and biopharmaceutical product development.
The data submitted by the pharmaceutical companies to the FDA must follow the CDISC standard. The important models of CDISC are-

i) Operational Data Model (ODM)- it facilitates the movement of clinical data collected from multiple sources to one operational database. The sources of the data are paper CRF, eCRF, patient diaries, etc. The model is a specification of a standard XML schema for the interchange and archive of clinical trials data and metadata.

ii) Analysis Data Model (ADM)- it defines a standard for analysis datasets that are used to generate statistical reports for regulatory submissions.The dataset should be ready for analysis to be performed using SAS procedures directly without any further work on the data. The names should have more descriptive labels in case of more than one dataset, like, Subject baseline Characteristics Analysis Dataset and Analysis Dataset Change from Baseline. Metadata is required to be submitted at each level for all the datasets involved.

iii) Study Data Tabulation Model (SDTM)- it defines a standard structure for data tabulations that are to be submitted as part of a product application to a regulatory authority such as the FDA. The current version being used is 3.1.1 SDTMIG.

iv) Laboratory Study Model(LSM)- it works towards the development of a standard model for acquisition and interchange of lab data which is the largest component of the Clinical Trial data.

About Author / Additional Info:
Geetanjali Murari
Email Id: