A Study to Learn How Well Nifurtimox Works and How Safe it is in Children Aged 0 to 17 Years With Chagas' Disease, an Inflammatory, Infectious Disease Caused by the Parasite Trypanosoma Cruzi

Researchers are looking for a better way to treat children who have an infectious disease caused by the parasite Trypanosoma cruzi (Chagas' disease).

Chagas'disease is an inflammatory, infectious disease caused by the parasite Trypanosoma cruzi. This parasite is mainly spread by insects called triatomine bug. If Chagas' disease is left untreated, it can later cause serious heart and digestive problems.

The study treatment nifurtimox has been used for more than 50 years to treat Chagas' disease. When used early after infection, it kills the parasite. In people who have long-term Chagas' disease, it's no longer possible to kill the parasite. However, nifurtimox may help slow the progression of the disease and its most serious complications.

Nifurtimox was developed for use in adults only, but has also been used in children (off-label) for over 40 years. Currently it is available for doctors to give to adults and to children. However, there are not enough data about nifurtimox in children.

The main purpose of this study is to learn how well nifurtimox works in children aged 8 months to less than 18 years with Chagas' disease. To answer this, the researchers will compare the amount of antibodies against the parasite Trypanosoma cruzi in the serum (fluid from blood without the clotting factors) between children treated with nifurtimox for 60 days with untreated children from the past (control group):

* 12 months and
* 4 years after the end of treatment. The data for the control group will come from 2 previous studies conducted in children.


Eligibility Criteria:
Inclusion Criteria:

Part 1:

* Male and female pediatric subjects aged 0 days to younger than 18 years
* Chagas' disease diagnosed/ confirmed for a) Subjects \< 8 months of age at randomization must demonstrate direct observation of Trypanosoma cruzi by concentration test; b) Subjects ≥ 8 months to \< 18 years of age at randomization must demonstrate a positive conventional ELISA result for both recombinant ELISA and total purified antigen ELISA

Part 2:

- Male and female subjects who were randomized and received at least one dose of their assigned 60- or 30-day regimen of nifurtimox treatment

Exclusion Criteria:

Part 1:

* Subjects aged 0 to 27 days who, at birth, were pre-term, weighed less than 2500 g, or had a maximum Apgar score \< 7 at 5 minutes
* Known evidence of Chagas' disease-related cardiomyopathy/ Chagas' heart disease
* Known evidence of Chagas' disease-related gastrointestinal dysfunction (e.g. megaoesophagus, megacolon, or both) or Chagas' digestive disease
* Serious manifestations of acute Chagas' disease, including myocarditis, meningoencephalitis, or pneumonitis
* Known evidence of Chagas' disease-related damage to the peripheral nervous system or peripheral neuropathy
* Clinically significant psychiatric disorder (e.g. moderate to severe depression, severe anxiety, or psychosis) or epilepsy
* Subjects with contraindications/ warnings to nifurtimox administration, or with conditions that may increase the risk of the undesirable effects of nifurtimox
* Subjects who have had previous treatment with trypanocidal agents or an accepted indication for antiparasitic therapy (e.g. reactivation of Chagas' infection due to immunosuppression by several diseases or treatment with steroids)
* Subjects living in housing conditions where there is no active or effective vector control to Trypanosoma cruzi reinfection as determined by Ministry of Health guidelines in each country

Part 2:

* Subjects with acute or chronic health conditions or congenital disorders which, in the opinion of the investigator, would make them unsuitable for participation in the clinical study
* Subjects living in housing conditions where there is no active or effective vector-control to Trypanosoma cruzi reinfection as determined by Ministry of Health guideline of the respective country
* Subjects with clinical manifestations of Chagas' disease-related gastrointestinal dysfunction or serious manifestations of acute Chagas' disease
* Immuno-compromised subjects (e.g. with human immunodeficiency virus or treated with immunosuppressive drugs)