Pharmacovigilance and new essential drugs in Africa: Zambia draws lessons from its own experiences and beyond

Abstract

Jolted into action by the thalidomide tragedy, developed Western countries began to establish national systems for identifying and responding to adverse drug reactions and events (or pharmacovigilance systems) about 40 years ago. These systems focus on side effects, adverse reactions, and drug interactions. In developing countries, especially in Africa, the scope for pharmacovigilance needs to be broader (despite the additional challenges this brings) because of growing problems with substandard and counterfeit drugs and the need to have an early warning signal system for the development of antimicrobial resistance to the ‘new essential drugs’ that are barely beyond the clinical trial stage in Africa, e.g. artemisinin-combination therapy (ACT) for malaria and antiretrovirals (ARV) for HIV/AIDS. Zambia learned important lessons from its own initial experiences in attempting to use ACT as a pathfinder for pharmacovigilance, as well as its experience with other drug information systems. In preparing its own renewed plans, it also drew lessons from international experience, including the weaknesses of the Food and Drug Administration's approach to pharmacovigilance in the USA, the UK's ‘yellow card scheme’, Brazil's fledgling pharmacovigilance systems for AIDS treatment, and the guidance provided by the World Health Organization and the Uppsala Monitoring Centre. These lessons are relevant for other African countries and even for developed countries seeking to improve pharmacovigilance systems.

Keywords:

• Pharmacovigilance
• post-marketing drug surveillance
• antimicrobial resistance
• drug reactions and interactions
• substandard and counterfeit drugs

The authors would like to thank Amy Nunn who, in order to help inform plans in Zambia, developed a mini-case study on recent experience with pharmacovigilance in Brazil. The research for this article was partially supported by the USAID-funded Health Services and Systems Program (HSSP) in Zambia; the views expressed by the authors do not necessarily reflect those of USAID.

Notes

1. The terms adverse drug reaction (ADR) and adverse drug event (ADE) can be defined differently in different contexts. For the sake of simplicity, we have used ADE as an all-embracing term for adverse events or reactions as discussed in this article.

2. These data are based on interviews with all relevant donor agencies, and careful consideration of any potential double-counting of funds that might have ‘lost their original identity’ as they flowed from one donor to another, e.g. Global Fund to UNICEF.

3. Planned reporting in Zambia will be ‘stimulated’ (actively encouraged) rather than being completely ‘spontaneous’, but this is still a passive type of surveillance, and will not provide both a denominator (number of patients exposed to drugs) and a numerator (number of patients with resistance), so reliable incidence rates cannot be calculated.

4. See http://www.usaid.gov/our_work/global_health/home/TechAreas/commrule.html or http://www.usaid.gov/policy/ads/200/humansub.pdf