The experimental scientific study published in The Lancet Infectious Diseases demonstrated that a shorter treatment with the drug benznidazole is as effective as the standard eight-week treatment. Here is the voice of the experts.
There are between 6 and 7 million people infected with the parasite that causes Chagas disease in the world. One of the difficulties found is having access to an effective treatment and its duration. With the aim of facilitating access and reducing side effects, a recent study was conducted and found that the two-week treatment for adults with chronic Chagas disease has similar efficacy to the current standard eight-week treatment with the drug benznidazole, with significantly fewer side effects.
The study was published in The Lancet Infectious Diseases. It consisted of a Phase 2 clinical trial conducted in three centres in Bolivia. The trial was led by Drugs for Neglected Diseases initiative (DNDi) and funded by the Global Health Innovative Technology Fund (GHIT) from Japan.
The trial was conducted between 2016 and 2018, in partnership with CEADES (Applied Science and Studies for Health and Environmental Development), a non-profit foundation from Bolivia, the Barcelona Institute for Global Health (ISGlobal) –a centre supported by “la Caixa” Foundation–, the Japanese pharmaceutical company Eisai, and the Argentine pharmaceutical company Elea Phoenix S.A.
If left untreated, the infection by the parasite that causes the disease can lead to damage to the heart and other vital organs. At present, treatment with benznidazole, one of the two drugs used to treat the disease, is effective but has limitations: the tablets are received for eight weeks and about 20% of the patients abandon treatment due to side effects, such as gastric intolerance, skin eruptions and neuromuscular problems.
Infection with the parasite causing Chagas has several transmission routes. One of them is the bite of insects that carry the parasite. It can also be transmitted from the infected mother to her child, and through transfusions of contaminated blood, among others (UN: news.un.org)
Today is World Chagas Disease Day, one of the most neglected diseases in the world, according to the WHO. Currently there are affected people both in rural and urban areas. One of the researchers that participated in the new study was the Argentine physician Sergio Sosa Estani, researcher at Conicet and responsible for the Chagas program of the Drugs for Neglected Diseases initiative (DNDi) in Latin America.
“We conducted the first controlled study involving 218 recruited patients, who were grouped to compare different durations and doses of treatment with benznidazole, alone or combined with fosravuconazole, and a group that only received placebo”, explained Sosa Estani. He considered that the results give “hope for people infected with Chagas disease, since a shorter treatment might remove some concerns of caregivers and patients, and will improve treatment adoption”.
It is still necessary to move to phase 3 of the investigation to confirm that the two-week regimen is as effective as the eight-week one. Marcelo Abril, executive director of Mundo Sano Foundation, confirmed to Infobae that the phase 3 clinical trial will be conducted this year, and will involve a higher number of patients from Argentina.
The protocol was approved by ANMAT, the regulatory agency, and will be launched before the end of the year by DNDi in partnership with ELEA-Phoenix and Mundo Sano Foundation to confirm the efficacy and safety of the two-week regimen of benznidazole.
The disease is caused by the protozoan parasite Trypanosoma cruzi. It is found mainly in endemic areas of 21 Latin American countries. If people are treated early, the infection can be controlled.
Infobae consulted Héctor Freilij, a paediatrician specialist in infectious diseases, former head of the National Chagas Program of the Ministry of Health and director of the journal of the Ricardo Gutiérrez’s Children Hospital of Buenos Aires city, who referred to the new study published in The Lancet Infectious Diseases: “It is a very valuable work to explore what happens if the drug regimens for patients infected with the Chagas-disease causing parasite are shortened”.
Dr Freilij, who did not participate in the study, indicated limitations in terms of the number of patients –which were also recognized by the authors in the conclusions– and proposed that more drugs for Chagas should be considered. “It is known that there might dormant parasites; hence, the diagnosis by PCR one year after the study might have failed to detect these dormant parasites. Therefore, it would be useful to conduct a longer study to better evaluate the efficacy of drugs targeting the parasite in the mid-and long-term”.
Freilij stated that drugs such as benznidazole target only the parasite. However, 30% of the people infected with the parasite can develop heart disease 10 years or more after having become infected. “It would also be important to search and investigate other drugs that may help to modulate the body’s inflammatory response that leads to the development of heart disease. Indeed, heart disease is not explained only by the presence of the parasite in the human body”.
For conducting the study, the organization DNDi received financial support of the Global Health Innovative Technology Fund (GHIT) from Japan; UK Department for International Development (UK Aid); the German Federal Ministry of Education and Research through KfW; the Dutch Ministry of Foreign Affairs; the Brazilian Ministry of Health; the Associação Bem-Te-Vi Diversidade, Brazil; the Fundação Oswaldo Cruz (Fiocruz), Brazil; and the Starr International Foundation, Switzerland.
According to Mariana Sanmartino, biologist and doctor in Education Sciences, “any development in the drugs for Chagas disease is positive, since this is one of the most neglected diseases in the world. As the authors of the study indicate, it is important that further research including a higher number of patients is conducted to obtain more evidences about the efficacy of the drug with a shorter regimen and that all the factors interfering with access to treatment are considered”.
People infected with Chagas disease very often have trouble in finding health care professionals available and are not treated properly, stated Mariana Sanmartino, researcher at Conicet, who appreciated the clinical trials performed to study drugs for this disease.
Dr Sanmartino, researcher at Conicet and member of the group What do we mean when we talk about Chagas disease?, highlighted that people that need care encounter different barriers. There are difficulties in having access to diagnosis and then to treatment. For example, they encounter barriers to access to the healthcare centres because of the distances, or to receive treatment from trained health teams. “Sometimes people consider that they need an ultra-specialized doctor –said Sanmartino–, but a general practitioner can also treat people infected with Chagas disease. In some cases, these are even not well treated, feel stigmatized and stop seeking a response from the healthcare system. Today, the focus should be on people and their rights”.