Safety monitoring of new anti-malarials in immediate post-marketing phase.

When a drug is newly marketed, there is limited safety information. Less than five thousand humans may have been exposed to the drug, making in impossible to be sure of detecting serious adverse reactions occurring less frequently than 1/1000. Post-marketing safety relies on spontaneous reporting of adverse reactions. Such reporting is usually incomplete and little use is made of drug use and clinical data in analysing for benefit versus risk. Observational epidemiological studies can be used to investigate drug risk hypotheses once these are made, but they are expensive and take time, during which people may be harmed if the hypothesis is correct. Launching drugs in developing countries, which may have little or no safety monitoring infrastructure, puts the onus on the sponsors to monitor the first thousands of patients exposed for adverse reactions. This can be done by maintaining patient records and using simple techniques to promote and facilitate reporting of unusual clinical events to a responsible body of experts. This work must be done in collaboration with national governments. This will help in the general promotion of benefit-risk thinking by those involved in all aspects of drug treatment.