Tetrapal – A New Technique for Malaria Drug Testing in Urine

Abstract

Tetrapal is a Joint Research Project developed within the framework of an original public-private partnership between the Ministry of Defence, the French University of Marseille and Exxon Mobil Corporation. Malaria control policies and their compliance controls are high priorities for both the French army and ExxonMobil. Both organizations are interested in further developing processes that can be used to verify that soldiers or employees are taking their malarial chemoprophylaxis as prescribed. Currently, compliance is enforced and verified by using High-Performance Liquid Chromatography (HPLC) techniques for detecting the presence of mefloquine, doxycycline, chloroquine and proguanil (a component of Malarone) in urine samples. This procedure cannot be performed in the field because it requires special expertise, structures and technology not available in the field. The program is very expensive due to the laboratory analyses and shipping procedures required to ship the samples to a qualified laboratory. There is also a delay of several weeks between sample collection and laboratory verification. Objectives of the Tetrapal project The TETRAPAL project consists of developing a fast-acting immunochemical method to detect anti-malarial drugs such as doxycycline, chloroquine, mefloquine, and proguanil, in the urine of persons taking chemoprophylaxis (Doxycycline, Savarine®, Lariam®, Malarone®, Chloroquine). The idea is to develop a Rapid Diagnostic Test (RDT). This RDT needs to be reliable, simple and easy to use on site by non-medical personnel. An "all in one" test that recognizes all types of anti-malarials is preferable. The final step will be to identify and contract with (an) industrial partner(s) for the commercialization of the method, manufacturing and distribution of the RDT. Technical aspects An RDT is a test using an immunochromatographic capture procedure with monoclonal antibodies that detect antigens (parasite-specific or, in our study, anti-malarial drug-specific) in lysed blood or plasma or urine. It uses a lateral-flow principle: the buffer "flows" along a nitrocellulose strip and passes over the capture and control lines. The researchers chose to develop a test to detect the existence of anti-malarial molecules in urine by immunocapture and competition on strips (lateral flow assay). The justification of the immunologic method is that use of antibody capture techniques can lead to very specific and sensitive tests, when chloroquine, mefloquine and doxycycline and proguanil are not totally metabolized and are eliminated in urine where they can be identified by monoclonal antibodies. Status after one year Antibodies against doxycycline, proguanil and chloroquine have been identified. Those are ready to be produced at an industrial level. Antibodies against mefloquine are still under laboratory research phase. The first experimental strips detecting chloroquine and proguanil (i.e. Malarone®) are expected to be ready for field testing in early 2008.

Enabling Factors for Improved Malaria Chemoprophylaxis Compliance

“…The urine tests verify the use of malaria chemoprophylaxis, although their protective levels can only be assessed through blood tests. In early 2012, a field test developed with the French Army9 for Proguanil and Mefloquine was implemented. It provides results in 10 minutes and enables more practical on-site verification and immediate feedback.…”