Fighting schistosomiasis with praziquantel

Over 200 million people in Africa suffer from the widespread tropical worm disease schistosomiasis. It is estimated that more than 200,000 die each year as a result of this chronic parasitic condition, which makes it the most common tropical disease in Africa after malaria. Schistosomiasis is widespread primarily in the tropical and subtropical areas of sub-Saharan Africa. In these regions, a vast majority of the population has no access to clean water and sanitary installations.

The disease is caused by flatworms and is spread through stagnant water. People become infected by the worm larvae in the water, while bathing, fishing, playing, washing their clothes, or working agricultural land. These larvae penetrate human skin and enter the blood vessels, where they grow into adult worms. The female's eggs infest inner organs such as the intestines, bladder, spleen, or liver, and often cause severe inflammation. Symptoms include severe abdominal pain, diarrhea, and bloody urine or stool. The infection rate is especially high among children, and the chronic symptoms that result are particularly serious. Schistosomiasis stunts growth, causes learning disabilities and leads to anemia.

Merck KGaA, Darmstadt, Germany has been supporting the World Health Organization (WHO ) since 2007 in the fight against schistosomiasis in Africa. Our efforts are thus in line with the United Nations Millennium Development Goals. In addition, they are part of the initiative to fight neglected tropical diseases that was launched by the Bill & Melinda Gates Foundation in early 2012. Merck KGaA, Darmstadt, Germany donates tablets containing the active ingredient praziquantel to WHO, which then distributes these mainly to African school children. Since the start of our Praziquantel Donation Program, over 100 million tablets have been donated. A total of more than 28 million children have been treated. In 2012 alone, Merck KGaA, Darmstadt, Germany supplied WHO with over 27 million praziquantel tablets. In 2012, an estimated seven million children were treated for schistosomiasis (final figures will be available mid-2013).

Praziquantel is the only active ingredient with which all forms of schistosomiasis can be treated. In addition, praziquantel is well-tolerated. WHO has therefore included it on its Model List of Essential Medicines. Merck KGaA, Darmstadt, Germany developed praziquantel in the 1970s as part of a research collaboration. Our plant in Mexico produces the tablets under the brand name Cesol 600®; we organize and finance the transport to Africa, and WHO coordinates local distribution.

Program expansion

Originally, our program was scheduled to end in 2017. However, Merck KGaA, Darmstadt, Germany decided at the end of 2011 to continue its efforts indefinitely. The goal, agreed upon in conjunction with WHO, is to eliminate the worm disease in Africa. To this end, Merck KGaA, Darmstadt, Germany intends to increase the number of tablets donated in the medium term, raising the total to 250 million annually. This will allow around 100 million children to be treated each year.

This planned donation has a value of approximately US$ 23 million per year; in 2012, Merck KGaA, Darmstadt, Germany invested US$ 2.85 million (2011: US$ 2.3 million) in the donation program. These figures include the logistics costs to ship the tablets from the production site in Mexico to Africa, but not the costs for the awareness program or the research into a pediatric formulation.

Educating people

In addition to the tablet donation, Merck KGaA, Darmstadt, Germany is also supporting an awareness program at schools in Africa; it uses comic booklets  and posters  to explain the causes of schistosomiasis, teaching pupils how to prevent the disease. In 2011, a pilot project was launched at schools in Senegal and Malawi; through 1,100 brochures and 130 posters, the project reached around 1,100 school children. WHO is currently adapting the materials based on the experience gained from the pilot regions. In 2013, the program is being launched in Senegal with 750,000 brochures and in Malawi with 250,000 brochures.

Optimizing the formulation

As part of the donation program expansion, Merck KGaA, Darmstadt, Germany is also working to optimize the formulation of the drug. For instance, pharmaceutical experts are currently developing a fruity coating intended to make it easier for children to take the tablets.

Research

Within the scope of a public-private partnership (PPP) , Merck KGaA, Darmstadt, Germany is researching a formulation of praziquantel for small children. Praziquantel tablets in their current form are suitable for adults and children over the age of six; for children younger than six, it is currently not possible to properly treat the disease. We believe that a pediatric formulation of praziquantel will be a significant step toward eliminating schistosomiasis in Africa. The partners of this public-private partnership, which was founded in July 2012, include Merck KGaA, Darmstadt, Germany, TI Pharma , Astellas Pharma Inc., and the Swiss Tropical and Public Health Institute (“Swiss TPH ”) in Basel.

Managing and monitoring

Our Praziquantel Donation Program (MPDP) is being conducted in partnership with WHO, with Merck KGaA, Darmstadt, Germany and WHO each contributing their particular expertise. Merck KGaA, Darmstadt, Germany produces the tablets and handles the costs for transporting the tablets to Africa. WHO manages, monitors, and documents the local distribution of the Praziquantel tablets and works with local authorities to implement the treatment at schools. WHO supplies the local data on morbidity rates and treatment frequency in the countries in which our Praziquantel Donation Program has been rolled out. The data for each country can be found in the WHO PCT databank . A steering committee consisting of representatives from WHO and Merck KGaA, Darmstadt, Germany convenes several times a year in order to review the program's progress and decide on its future course. The last meeting was held in Kenya in November 2012.

Evaluation

As part of a Bertelsmann Foundation project on corporate social engagement, we collaborated on the development of the "IOOI" method  (Input, Output, Outcome, Impact), a way of gauging and assessing social engagement. We have applied this method to our donation program to combat schistosomiasis, which allows us to evaluate the progress of the project.