Short-course eflornithine in Gambian trypanosomiasis: a multicentre randomized controlled trial.

OBJECTIVE: A randomized controlled trial was conducted to determine whether 7 days of intravenous eflornithine (100 mg/kg every 6 h) was as effective as the standard 14-day regimen in the treatment of late-stage Trypanosoma brucei gambiense trypanosomiasis. METHODS: A total of 321 patients (274 new cases, 47 relapsing cases) were randomized at four participating centres in Congo, Côte d'Ivoire, the Democratic Republic of the Congo, and Uganda to one of these treatment regimens and followed up for 2 years. RESULTS: Six patients died during treatment, one of whom was on the 7-day regimen, whereas the other five had been on the 14-day regimen (P = 0.2). The response to eflornithine differed markedly between Uganda and other countries. Among new cases in Uganda, the 2-year probability of cure was 73% on the 14-day course compared with 62% on the 7-day regimen (hazard ratio (HR) for treatment failure, 7-day versus 14-day regimen: 1.45, 95% CI: 0.7, 3.1, P = 0.3). Among new cases in Côte d'Ivoire, Congo, and the Democratic Republic of the Congo combined, the 2-year probability of cure was 97% on the 14-day course compared with 86.5% on the 7-day regimen (HR for treatment failure, 7-day vs 14-day: 6.72, 95% confidence interval (CI): 1.5, 31.0, P = 0.003). Among relapsing cases in all four countries, the 2-year probability of cure was 94% with 7 days and 100% with 14 days of treatment. Factors associated with a higher risk of treatment failure were: a positive lymph node aspirate (HR 4.1; 95% CI: 1.8-9.4), a cerebrospinal fluid (CSF) white cell count > or = 100/mm3 (HR 3.5; 95% CI: 1.1-10.9), being treated in Uganda (HR 2.9; 95% CI: 1.4-5.9), and CSF trypanosomes (HR 1.9; 95% CI: 0.9-4.1). Being stuporous on admission was associated with a lower risk of treatment failure (HR 0.18; 95% CI: 0.02-1.4) as was increasing age (HR 0.977; 95% CI: 0.95-1.0, for each additional year of age). DISCUSSION: The 7-day course of eflornithine is an effective treatment of relapsing cases of Gambian trypanosomiasis. For new cases, a 7-day course is inferior to the standard 14-day regimen and cannot be recommended.

[Therapeutic failure of melarsoprol among patients treated for late stage T.b. gambiense human African trypanosomiasis in Uganda]. / Echecs thérapeutiques du mélarsoprol parmi des patients traités au stade tardif de trypanosomose humaine africaine à T. b. gambiense en Ouganda.

The failure rate of melarsoprol after treatment of late stage cases of Human African Trypanosomiasis (HAT) is usually under 7%, even though the drug has been used for such treatment over the past 50 years. We report a melarsoprol treatment failure rate of 26.9% among 428 patients treated in Northern Uganda. Whatever its origin, this observation, the first documented in a HAT focus, is alarming, particularly since no second line trypanocidal drug is actually available for the treatment of late stage HAT. We believe that the current worrisome situation of HAT in several African countries and the risk of emergence of other foci of resistance, argue in favour of a greater attention on the part of the scientific community and the pharmaceutical companies being paid to this problem.

Risk factors for treatment failure after melarsoprol for Trypanosoma brucei gambiense trypanosomiasis in Uganda.

We evaluated the treatment failure rate among late-stage human African trypanosomiasis (HAT) patients treated with melarsoprol in Arua, northern Uganda, between September 1995 and August 1996, and identified the risk factors for treatment failure. We conducted a retrospective cohort study in October 1998, and performed a survival analysis. A treatment failure was defined as a late-stage HAT patient fully treated with melarsoprol and classified as an HAT case at any follow-up visit within 2 years after treatment. Among 428 patients treated in the study period, 130 (30.4%) were identified as treatment failure within 2 years after discharge. The multivariate analysis showed that patients who experienced treatment failure after melarsoprol were more likely to have been admitted as a relapsing case (relative hazard, RH = 11.15 [6.34-19.61]), and to have been diagnosed with trypanosomes in the lymph nodes (RH = 3.19 [2.10-4.83]) or in the cerebrospinal fluid (CSF) (RH = 1.66 [1.09-2.53]). The risk of treatment failure also increased with the number of cells in the CSF. The treatment failure rate after melarsoprol observed in Arua is greatly above the expected figures of 3-9%. More research is needed to confirm whether it is related to the variation of melarsoprol pharmacokinetics between individuals, or if it is associated with a reduced susceptibility of the trypanosomes to melarsoprol. The study emphasizes the need for second-line drugs to treat patients that have already received one or several full course(s) of melarsoprol.