Table 2 Exclusion criteria

• Having previously received treatment with benznidazole or nifurtimox (either completely or incompletely)

• Signs and/or symptoms of severe cardiac form of Chagas disease (as confirmed by local national guidelines)

• Impossibility to complete the specified protocol follow-up visits

• Acute or chronic health problems that, in the opinion of the principal investigator, may interfere with the evaluation of the efficacy and/or safety related to the drug (for example, acute infections, human immunodeficiency virus infection, liver or kidney disease)

• History of alcohol abuse

• Known hypersensitivity to metronidazole drugs

• Concomitant use or history of use of allopurinol, antimicrobial, antiparasitic, or antifungal agents

• Having laboratory parameters outside the range of normal or that are considered clinically relevant by the responsible physician:

 ◦ Total leukocyte count must be within the normal range, with an acceptable range of ± 5%.

 ◦ Total platelet count must be within the normal range up to 550,000/mm³ or 550 × 10⁹/L.

 ◦ Total bilirubin must be within the normal range.

 ◦ Transaminase levels must be within the normal range, with an acceptable range of 25% above the upper limit of normal (ULN).

 ◦ Total creatinine level must be within the normal range, with an acceptable variation of 10% above the ULN.

 ◦ Alkaline phosphatase level must be within the normal range up to < 2.5× ULN.

 ◦ Gamma glutamyl transferase level must be within the normal range up to 2× ULN.

 ◦ Fasting glucose must be within the normal range.