Evidence and the Introduction of new prescription drugs to the market

Prescription medicines are allowed into the market “only after” they have been tested in animal and human studies and the results evaluated to the satisfaction of drug regulatory authorities. Regulatory authorities are expected to ensure the scientific rigor and validity of the study and ensure that benefits outweigh any risks that the medicines may cause. Current standards of evidence involve the use of a clinical trial design to test the effectiveness of the medicines. These medicines are compared against a standard of treatment (control) and/or a placebo (the use of a placebo is not encouraged nowadays unless there is no alternative). There are several ways to add value to a clinical trial including randomization, sample size estimates and choice of outcome measures. Clinical trial protocols are now expected to be registered in a public or government database as another safety measure to ensure data integrity. Regulatory authorities are also expected to evaluate post market entry studies and results of the approved drugs.

Given all these “safeguards”, one will presume that the prescription medicines that make it to the market are really worth it and well studied (especially since some or most of them may not  necessarily fall into the affordable bracket).

A recent study published in the BMJ throws light on some startling (or is it) facts based on a study that looked at the availability of evidence of benefits on overall survival and quality of life of cancer drugs approved by the European Medicines Agency (EMA) from 2009 to 2013. This was a retrospective study that examined publicly available and accessible regulatory and scientific report on prescription medicines for cancers approved by the EMA for the study period.

The study concluded that most drugs entered the market without evidence of benefit on survival or quality of life. At a minimum of 3.3 years after market entry, there was still no conclusive evidence that these drugs extended survival of patients or improved quality of life for most cancer indications. When there were survival gains over existing treatment or placebo, these were marginal.

Note that this is the state for anti cancer drugs- an area of strict regulation and “cutting edge” research and development.

How do you interpret this study?

  1. The study has several limitations that have been described by the author.  Where reported results have been ambiguous or unclear or incomplete, the authors have decided to err on the side of the prescription drugs and the conclusions of the EMA.
  2. The studies have considerable variation in the reporting of quality of life endpoints. It is possible that the authors of this study have over estimated the proportion of drugs that offer improvements in quality of life
  3. The appropriateness of the clinical trial study design used or the comparators chosen is a limitation. For example, a “poorly” chosen or inappropriate control can  overestimate the benefits of the medicine.
  4. The authors have not included studies with negative results in the study period unless they were considered as pivotal studies.

What does this mean if you are a medical practitioner, especially an Oncology practitioner?

  1. The most important takeaway is to explore, assess or analyze, and understand the evidence yourself before you prescribe a new medicine even if they are presented to you with the assurance that they have been approved by the regulatory authorities.
  2. Do take time off to source the primary article and look over that with a critical eye. Focus on the reported research methods, outcome measures and the validity of the study.
  3.  When expensive new medications are offered to patients without clinically meaningful benefits, it can harm individual patients, waste individual, organizational and societal resources, and undermine the provision of quality affordable and equitable healthcare.
  4. Understand the medications you prescribe.


What does this mean if you are an individual who receives prescription medicine?

  1.  Not every new medicine or expensive medicine actually adds value. Newer and Expensive do not necessarily always translate to good for you
  2. Do not hesitate to discuss your prescriptions with your doctor. It is your body. Make sure you understand the prescription, the dose, the side effects, alternates to the prescribed medicine, the rationale for the prescription.
  3. Do not hesitate to ask your doctor regarding the evidence related to the prescriptions they write you (diagnostic tests as well).
  4. Does your doctor understand the prescriptions they write?


A few references to explore for further information (Read through and arrive at your own conclusions)

  1. http://www.bmj.com/content/bmj/359/bmj.j4530.full.pdf
  2. http://www.bmj.com/content/bmj/359/bmj.j4528.full.pdf





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