Clinical Trials

Clinical
Trials

   

• Sharon Conroy, John
  Mclntyre, et al (Academic
  Division of Child Health, University of Nottingham,
  Derbyshire Children”s Hospital, Queen’s Medical
  Centre, Nottingham, UK)

  
   
  

  Drug trials in children: problems and the way
  forward.

  
  
  
  
  Br.J.Clin Pharmacol, 49: 93-97.
  
  
    
  
  
  Summary :
  Drug-licensing system was introduced with the
  Medicines Act of 1968, following the thalidomide
  disaster, with the aim of ensuring that medicines
  are safe, effective and of high quality. Several studies have shown unlicensed and
  off-label drug use for hospitalized children with
  upto 90% of newborn infants in intensive care
  receiving either unlicensed or off-label treatment.

  
  
  
    
  
  Unlicensed
  medicines may be those compounded in a hospital
  pharmacy and their quality may be variable. The term off-label refers to use of a
  medicine outside specifications of the product
  license different dosage to that recommended, in
  different age group, by different route or for a
  different indication.

  
  
  
    
  
  Pharmaceutical
  companies may have been reluctant to study medicines
  in children, as market for children is smaller,
  ethical difficulties, problems with blood sampling
  and recruiting sufficient number of children.

  
  
  
    
  
  A new
  European guidance has come into force since
  September 1997 in relation to clinical trials for
  conditions in children where there is either no or
  inadequate treatment. At present the guidance divides
  drugs into 4 categories and gives recommendations.

  
  
  
    
  
  Blood
  sampling: It is considered ethical, if full informed
  consent is obtained from the carer or child (if more
  appropriate). Use of topical local anaesthetic cream
  has simplified this problem.
  Number of blood samples should be minimum. Four blood samples at appropriate time points
  for drugs excreted by kidneys, are adequate if
  adult-data and half-life are available. For newborns, microassays are essential. Non-invasive techniques like erythromycin
  breath test need to be developed.

  
  
  
    
  
  The
  guidance regarding clinical trials in children-4
  categories are :
  
    
  
  (1)Diseases
  affecting children exclusively – 
  Clinical trials in children may start before
  any adult human experience.
  
    
  
  (2)
  Diseases mainly affecting children, or diseases
  having different natural history in children – 
  Clinical trials at an early stage in clinical
  development.

  
  
  
   
  
  (3)
  Diseases occurring in adults and children, for which
  there is currently no treatment – clinical
  trials needed following demonstration of safety and
  reasonable efficacy, in adults.
  
   
  
  (4)
  Diseases occurring in adults and children for which
  treatment exists – clinical
  trials in children should follow completion of adult
  phase 3 trials.