Why End Point Analysis is Integral to Clinical Study

End points are the primary outcomes measured in clinical trial to demonstrate the safety and efficacy of the interventions. Based upon the pathogenesis of disease and nature of interventions various end points are measured. For large scale double blinded controlled trials, a group of bio-statisticians will analyse data and verify the the end points by objective evidences. Also physician will determine the efficacy of the treatment given in the form of clinical report and examinations findings. based upon the result obtained through both the means, fate of clinical trial will be determined.

        Why End points need to be analysed ?

• This is regulatory requirement that authority will check

  

  Validated

  whether primary outcome has been analysed or not. Before completing perennial study, end point analysis has to happen when the study was ongoing. 
• For safety of trial participants, the effect of new treatment or the control i.e. standard treatment or placebo needs to be evaluated in clinical, laboratory and patient experience basis. 
• Harmony should be maintained between clinical reports prepared by investigators and the analysis made by bio-statistician. End point analysis provides the consideration for  the both. 
• In case disease of study has aggressive pathogenesis, end point analysis help whether to continue the same treatment or to switch the another. 

     Types of the End points In clinical trials

 Some outcomes can be measured by clinicians by clinical examinations to demonstrate the progress of the disease, but in certain situations it has to be measured by analysing the Investigations reports. Former method of analysing end points is called Clinical endpoint and later is known as surrogate endpoint. 

• Clinical Endpoint: Investigator will determine whether improvement in clinical features of disease shows progressive outcome or not. It includes Improvement in Symptoms, Signs, functional ability of organs and overall improvements. For the study of disease like Myocardial infarction, stroke, trauma, Respiratory and other infections, epilepsy, Gastroenteritis,  etc. Clinical endpoints gives the better Understandings. 
• Surrogate End points: surrogate endpoints is used when direct clinical outcome measurement is not possible and predictions are made from the laboratory investigations. Different Bio-markers are used to predict the disease progression. for example: Random Blood sugar measurement gives the idea of Diabetes progression, urinalysis for Kidney disease, serum cholesterol level measurement for atherosclerosis and so on. All these Surrogate End points should undergo validation by regulatory authority like FDA and only validated one can be employed by investigators. 

                                 For most of the Clinical trials, both measurement of clinical and surrogate end point is employed and  harmonization has to be established between the findings. Surrogate End points once validated by scientific analysis  to be used for that particular clinical study are called Bio-markers. Depending  upon disease different Bio-markers can be used like molecular, histologic, radio-graphic or physiologic. 

              End point in cancer trial 

Cancer trial are different than other trials in terms of clinical outcome, where death is the mostly anticipated Clinical outcome.  Therefore, survival is considered to be the one of the major positive outcome in such trial. Here are the different types of clinical trial endpoint specially practiced in cancer treatment trials.  

Disease free survival (DFS) : Time between completing treatment and recurrences of signs and symptoms of disease. 

Progression Free Survival (PFS) : Time measured after treatment up-to further progression of disease, specially used for highly aggressive cancers. 

Response Rate (RR) : response of drug by shrinking or disappearing the cancer after treatment. There is no control arm in such trials and response is calculated in percentage. 

Overall Survival (OS) : Time between introduction of treatment upto death of patient, irrespective of any cause. Specially in cases of advanced cancer, this is being measured. 

Quality of life (QOL) : measurement of drug's impact on sign / symptoms of disease including pain, ability to perform regular activities etc. Such data are taken as patient-reported-outcome and results are subjective to individual experiences. 

                                           

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