Safety Profile of Nifurtimox for Treatment of Chagas Disease in the United States

• Published in: Clinical infectious diseases Vol. 63; no. 8; pp. 1056 - 1062
• Main Authors: Forsyth, Colin J., Hernandez, Salvador, Olmedo, Wilman, Abuhamidah, Adieb, Traina, Mahmoud I., Sanchez, Daniel R., Soverow, Jonathan, Meymandi, Sheba K.
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 15.10.2016
• Subjects: Adult; Aged; and Commentaries; ARTICLES AND COMMENTARIES; Chagas Disease - drug therapy; Chagas Disease - epidemiology; Chagas Disease - parasitology; Drug dosages; Drug-Related Side Effects and Adverse Reactions - diagnosis; Drug-Related Side Effects and Adverse Reactions - epidemiology; Drug-Related Side Effects and Adverse Reactions - etiology; Female; Humans; Infectious diseases; Kaplan-Meier Estimate; Male; Middle Aged; Nifurtimox - adverse effects; Nifurtimox - therapeutic use; Phenotype; Risk Factors; Severity of Illness Index; Side effects; Symptom Assessment; Treatment Outcome; Trypanocidal Agents - adverse effects; Trypanocidal Agents - therapeutic use; Trypanosoma cruzi; United States - epidemiology; United States > US; USA; Chagas disease; side effects; nifurtimox; benznidazole; Trypanosoma cruzi
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1093/cid/ciw477

Background. Nifurtimox is 1 of only 2 medications available for treating Chagas disease (CD) and currently the only drug available in the United States, but its safety and tolerance have not been extensively studied. This is the first study to evaluate tolerance of nifurtimox in US patients with CD. Methods. This investigation assessed side effects in a sample of 53 patients with CD, all Latin American immigrants, who underwent treatment with nifurtimox (8–10 mg/kg in 3 daily doses for 12 weeks) from March 2008 to July 2012. The frequency and severity of adverse events (AEs) was recorded. Results. A total of 435 AEs were recorded; 93.8% were mild, 3.0% moderate, and 3.2% severe. Patients experienced a mean of 8.2 AEs; the most frequent were anorexia (79.2%), nausea (75.5%), headache (60.4%), amnesia (58.5%), and >5% weight loss (52.8%). Eleven patients (20.8%) were unable to complete treatment. Experiencing a moderate or severe AE (odds ratio [OR], 3.82; P < .05) and Mexican nationality (OR, 2.29; P < .05) were significant predictors of treatment discontinuation, but sex and cardiac progression at baseline were not. Patients who did not complete treatment experienced nearly 3 times more AEs per 30-day period (P = .05). Conclusions. Nifurtimox produces frequent side effects, but the majority are mild and can be managed with dose reduction and/or temporary suspension of medication. The high frequency of gastrointestinal symptoms and weight loss mirrors results from prior investigations. Special attention should be paid during the early stages of treatment to potentially severe symptoms including depression, rash, and anxiety.