A widely used menstrual cramp – mefenamic acid (trade name Ponstan) – can be effective in treating schistosomiasis. The discovery was made by researchers at the University of Guarulhos studying drug repositioning, i.e. new applications for existing drugs. After laboratory and animal testing, clinical trials are lacking in humans, so anti-inflammatory worms can be prescribed.
The study showed that Ponstan reduced parasite load by more than 80% in mice infected with Schistosoma mansoni. According to researchers, this percentage exceeds the "gold standard" set by the World Health Organization (WHO) for new medicines. Currently, there is only one cure for schistosomiasis, praziquantel. The efficacy of mefenamic acid may be even greater than the available antiparasitic as it also acts in the parasite's larval phase.
According to WHO data, schistosomiasis affects more than 240 million people worldwide. Professor Josue de Moraes of the University of Guarulhos points out that this is a neglected disease, and although it affects a significant proportion of people, more advanced research, vaccines and treatments are lacking. "We're talking about poverty diseases. The pharmaceutical industry, when looking at this audience, will not want to develop a new drug, "says the study's author.
According to Moraes, the production of a new drug involves at least 1.5 billion years of research, and since the disease mainly affects the poor, there is no interest in the pharmaceutical industry. "The advantage of repositioning [de fármaco] is that this is something that already exists, that is already approved, is already available in drugstores and if we can understand that this medicine has a different application from that used, I will eliminate that time and cost, "explained the teacher.
The drug repositioning study, developed at the University of Guarulhos, began with an analysis of 73 non-steroids marketed in Brazil and other countries. Mephenic acid showed the most promising results as antiparasitic. The discovery, which was supported by the State Foundation for Research Assistance in Sao Paulo (Fapesp), was published in the Lancet Group's EbioMedicine magazine.
The transmission of schistosomiasis is associated with sites without adequate sanitation and through contact with water with snails infected by disease-causing worms. Schistosoma mansoni worms settle in the veins of the patient's mesentery and liver. The infected individual has no symptoms within the first two weeks, but the condition can develop and cause chronic health problems and death.
Moraes points out that once clinical trials on humans have started, if Ponstan's efficacy for schistosomiasis has been demonstrated, the leaflets may be changed within one year and treatment recommended. "This is a region where you have people with the disease and receive treatment and follow the healing process. The only step left now is this. All the research needed for the development of medicine has been done, "he explained.
edition: Jose Romildo