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[e-drug] WHO Prequalification Project
- From: "E-Drug" <e-drug@healthnet.org>
- Date: Mon, 16 May 2005 16:15:36 +0200
E-DRUG: WHO Prequalification Project
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[The WHO Pharmaceutical newsletter (see http://www.who.int/medicines/library/pnewslet/pn2005_2.pdf#page=20) has a 3-page summary of the WHO Prequalification project, which might interest E-druggers (extracted below).
The full WHO PQ website is at: http://mednet3.who.int/prequal/
The lists of prequalified ARVs, TB and malaria drugs are downloadable, as well as all explanations how the PQ system works. WB]
WHO and its drug Prequalification Project: an overview
This little known part of WHO is effective and has teeth that can bite rapidly(1)
Established in 2001, the UN Prequalification Project is an action plan for expanding access to medicines for the
hardest hit by HIV/AIDS, Tuberculosis and Malaria while ensuring front-line quality assurance in every step of
the medicines supply chain.
The prequalification team within the Department of Medicines Policy and Standards in WHO handles those
aspects of the project that ensure safe and efficacious drugs of good quality. The team prepares a list of
prequalified medicines that meet certain pre-determined criteria. Drug procurement agencies can then refer to
such a list while placing their orders.
Working with a small, quiet and committed group the prequalification team has been successfully addressing
the problems of substandard and counterfeit medicines that waste resource, lead to treatment failure, and
greatly erode patient confidence and goodwill. With this article, we bring to our readers the reasons for and the
remit of the prequalification project and how it operates.
The challenges
The triple menace: HIV/AIDS, tuberculosis (TB) and malaria
Annually, more than six million people die of HIV/AIDS, TB and malaria, compounding the effects of poverty
and social inequities in many developing countries. HIV/AIDS has destroyed communities, health-care systems
and put a shadow upon the future of entire countries. In poor countries, six million people with HIV/AIDS need
immediate antiretroviral therapy. Less than eight per cent get it.(2)
There is a clear need for programmes to improve access to medicines in these sectors. But, for improved access
to bear real benefits, all these programmes have to ensure access to medicines of sound quality, safety and
efficacy.
Accelerated access and quality assurance
Efforts to accelerate access to pharmaceutical products used in the treatment of these major impact diseases
through negotiation and generic competition, have highlighted the importance of building quality assurance into
procurement systems for pharmaceutical products and diagnostics. Currently, about 20% of countries have well
developed and operational medicines regulation(3); the rest have either no or limited capacity to adequately
regulate the safety, efficacy and quality of medicines circulating in their markets.
In the absence of a quality assurance system, public health agencies risk sourcing substandard, counterfeit and
contaminated pharmaceutical products leading to product recalls, waste of resource and mone, with added
health risks to patients. While strengthening regulatory systems remains WHO's priority and will continue as
part of ongoing health-care initiatives, there is an immediate need to address current gaps in the quality and
supply of medicines for major impact diseases.
Treatment failure and risk of resistance
Substandard medicines could result in treatment failure and resistance while exposing patients to the potential
risks of chemical impurities. The high failure rate in quality control tests for the antimalarial chloroquine tablets
in some sub-Saharan African countries in a recent WHO study highlights this. Only 58% of the medicines tested
had an acceptable level of chloroquine content and only 25% had acceptable dissolution properties. The study
authors have suggested that poor quality chloroquine may be among the causes of the high rate of resistance
in these countries.(4)
Treating patients with poor quality medicines may result in low content of active ingredient and/or low
bioavailability leading to drug under-dosage, thus potentially promoting the development of resistance. A
system needs to be in place to ensure good manufacturing and clinical practices.
Good Manufacturing Practices (GMP): lack of compliance
In some countries, illegal manufacturing, distribution (including uncontrolled sales in market places and on
streets) and smuggling of medicines are widespread. Even manufacturers who fail to comply with good
manufacturing practice (GMP) requirements can still produce medicines for domestic use and for export, no
doubt greatly undermining the quality of medicines circulating in the market.
Issues of bioequivalence
Increased availability of medicines can translate into improved access only if these medicines are affordably
priced. Quite often, competitive prices are realized through multi-sourcing of products. In those instances
where multi-source, generic products are being introduced, it is important to ensure that these generic products
are interchangeable with the innovator products in being pharmaceutically and therapeutically equivalent.
An impartial process, that critically evaluates all generic product 'claims' for meeting quality specifications and
inspects the manufacturing facility, can ensure that multi-source products are of good quality and
therapeutically equivalent to the innovator products.
In short, the WHO commitment to scaling up access to medicines for major-impact diseases is of little relevance
to public health if quality, safety and efficacy issues are ignored. The UN Prequalification Project was thus born
for ensuring quality, efficacy and safety of priority medicines.
Organization of the overall Prequalification Project
The project is organized and managed by WHO on behalf of the United Nations; UNICEF, UNFPA, UNAIDS are
key UN partners with the support of the World Bank. WHO provides the technical and scientific support for
quality assurance of medicines and works in close cooperation with qualified assessors and inspectors from
national drug regulatory authorities as well as national quality control laboratories of developed countries (e.g.,
Australia, Canada, EU Member States, Switzerland). Qualified experts from other countries also contribute
(e.g., Brazil, Indonesia, South Africa, Uganda, United Republic of Tanzania).
Objectives of the WHO prequalification exercise
The WHO prequalification process aims to:
1. Propose a list of prequalified products as manufactured in sites that meet WHO norms and standards.
2. Follow-up products and manufacturing facilities for quality issues.
3. Ensure that requalification and update of the original approved list is carried out periodically and that
variations and changes are correctly controlled.
4. Help national drug regulatory authorities to build capacity in assessment, inspection and control of
medicines for priority diseases.
Applying for prequalification
Products identified as being of public health significance are listed on the Prequalification Project web site under
"Invitations for Expression of Interest (EOIs: http://mednet3.who.int/prequal).(5) These products are generally
selected from the WHO Model List of Essential Medicines. Any manufacturer or supplier of such a product is
eligible for assessment in the Prequalification Project by applying (with product dossier etc.) in conformity with
WHO guidelines.
The process of prequalification
A team of WHO appointed assessors drawn from national competent authorities will assess the product data as
submitted in the dossiers by the interested manufacturers. Additionally, samples may also be analysed for
quality control and compared with specifications as provided in the dossier. The manufacturing site(s) and the
clinical site (see bioequivalence studies below) listed in the product dossier are inspected on all aspects of Good
Manufacturing Practices (GMP) and Good Clinical/Laboratory Practices (GCP/GLP), respectively, by a team
appointed by WHO. Normally GMP inspections take a minimum of three consecutive days. In all, the entire
process, from receipt of the dossier to prequalification of the product takes about two to four months provided
the product dossier is complete at the time of submission and the mentioned sites are up to standards when
inspections are due. Frequently however, additional data are requested by the assessors and/or the mentioned
sites need to be upgraded to meet requirements. In such cases the time for prequalification of a product may
be considerably longer.
Requalification
Manufacturers are required to apply for requalification of their products three years following prequalification.
Requalification involves reassessment of the product data as provided in the original product dossier and reinspection
of the relevant site(s) for continued compliance.
Bioequivalence studies
In case of multisource (generic) products, therapeutic equivalence is mostly demonstrated through a
bioequivalence study carried out by an independent organization, company, academic institution, research
organization or laboratory. Where bioequivalence studies are conducted through contract research
organizations (CROs), the CRO study also needs to be inspected as per WHO guidelines.
Outcomes
The immediate outcomes of the WHO prequalification process include the list of prequalified products for
treating priority diseases, harmonization of quality requirements for international procurement organizations
and strengthening of collaboration between WHO, other UN agencies, related organizations and drug regulatory
authorities.
Earlier last year the prequalification process came under some criticism when several antiretroviral drugs were
'de-listed' due to non-compliance with good clinical and laboratory practices (see the prequalification web site
for the findings at these inspections, including an additional draft guidance for Contract Research Organizations
conducting bioequivalence studies).(5) Two of the products have since been put back on the list after the
manufacturer carried out new bioequivalence studies and demonstrated that these two drugs were
bioequivalent to and, therefore, as effective and safe as the originator products. Thus, while the de-listing
might affect the number of drugs to choose from in the immediate sense, the process always aims to safeguard
the patients' well-being. Equally, it shows that here is an impartial system to enforce quality-driven measures,
even when dealing with established manufacturers. It is obvious that the prequalification process exists to
ensure that "some of the most important drugs are being made safely available in the parts of the world where
they are most needed".(1)
References:
1. Editorial, The Lancet, Volume 364, Number 9448, 2004.
2. The 3 by 5 initiative web site: http://www.who.int/3by5/about/en/
3. WHO Policy Perspectives on Medicines: Effective medicines regulation: ensuring safety, efficacy and
quality, November 2003, World Health Organization.
4. The quality of antimalarials. A study in selected African countries. Geneva, WHO, 2003.
5. WHO Prequalification Project web site: http://mednet3.who.int/prequal/
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