Deferiprone (L1) as an adjuvant therapy for Plasmodium falciparum malaria. Effect of iron chelation therapy on recovery from deep coma in children with cerebral malaria. Effect of phenobarbital on seizure frequency and mortality in childhood cerebral malaria: a randomised, controlled intervention study. Assessment of the effect of the oral iron chelator deferiprone on asymptomatic Plasmodium falciparum parasitemia in humans. A comparative clinical trial of sequential treatments of severe malaria with artesunate suppository followed by mefloquine in Thailand. Controlled trial of lamotrigine (Lamictal) for refractory partial seizures.
Mortality due to Plasmodium falciparum infection remains high in India, hence any modality of treatment which can improve the outcome of this disease is worth exploring. The present study was undertaken to see whether addition of an oral iron chelator, deferiprone (L1) to the conventional treatment regime for P. falciparum infection improves the clinical course and final outcome.
                In this prospective, randomised double blind trial, 45 consecutive patients with P. falciparum infection were randomised into two groups. Patients in Group I (control group, 21 patients) received standard quinine and doxycycline therapy along with supportive therapy and placebo capsules for 10 days. Patients in Group II (24 patients) received the same treatment as Group I but in place of placebo capsule received deferiprone capsules 75 mg/kg/day in 12 hourly divided doses. The parameters evaluated included the time taken in resolution of parasitaemia, fever and coma, differences in final outcome i.e., death or other severe complications, and side effects and deferiprone tolerance.
                Four patients in Group I and two in Group II died (P > 0.05). The resolution of fever and coma was significantly faster in Group II (P < 0.05) and parasitaemia cleared 24 h earlier in this Group. The drug was well tolerated and had no side effects.
                Deferiprone (L1) seems to be a promising agent as an adjuvant in the treatment for severe P. falciparum malaria infection. Cerebral malaria is a severe complication of Plasmodium falciparum infection in children, with a mortality rate of 15 to 50 percent despite antimalarial therapy.
                To determine whether combining iron chelation with quinine therapy speeds the recovery of consciousness, we conducted a randomized, double-blind, placebo-controlled trial of the iron chelator deferoxamine in 83 Zambian children with cerebral malaria. To be enrolled, patients had to be less than six years old, have P. falciparum parasitemia, have normal cerebrospinal fluid without evidence of bacterial infection, and be in a coma from which they could not be aroused. Deferoxamine (100 mg per kilogram of body weight per day, infused intravenously for 72 hours) or placebo was added to standard therapy with quinine and sulfadoxine-pyrimethamine. The time to the recovery of full consciousness, time to parasite clearance, and mortality were examined with Cox proportional-hazards regression analysis.
                The rate of recovery of full consciousness among the 42 patients given deferoxamine was 1.3 times that among the 41 given placebo (95 percent confidence interval, 0.7 to 2.3); the median time to recovery was 20.2 hours in the deferoxamine group and 43.1 hours in the placebo group (P = 0.38). Among 50 patients with deep coma, the rate of recovery of full consciousness was increased 2.2-fold with deferoxamine (95 percent confidence interval, 1.1 to 4.7), decreasing the median recovery time from 68.2 to 24.1 hours (P = 0.03). Among 69 patients for whom data on parasite clearance were available, the rate of clearance with deferoxamine was 2.0 times that with placebo (95 percent confidence interval, 1.2 to 3.6). Among all 83 patients, mortality was 17 percent in the deferoxamine group and 22 percent in the placebo group (P = 0.52).
                Iron chelation therapy may hasten the clearance of parasitemia and enhance recovery from deep coma in cerebral malaria. Seizures commonly complicate cerebral malaria and are associated with an increased risk of death and neurological sequelae. We undertook a randomised study to assess the efficacy of intramuscular phenobarbital in preventing seizures in childhood cerebral malaria.
                Children with cerebral malaria admitted to one hospital in Kilifi, Kenya, were randomly assigned a single intramuscular dose of phenobarbital (20 mg/kg) or identical placebo. Clinical tolerance was assessed at the start of the trial, with particular reference to respiratory depression and hypotension. Seizures were timed and recorded, and treated in a standard way. Plasma phenobarbital concentrations were measured. Analyses were by intention to treat.
                440 children with cerebral malaria were admitted to the hospital; 100 were not recruited to the study. Of the remaining 340, 170 received phenobarbital and 170 placebo. The drug was adequately absorbed and well tolerated. Seizure frequency was significantly lower in the phenobarbital group than in the placebo group (18 [11%] vs 46 [27%] children had three or more seizures of any duration; odds ratio 0.32 [95% CI 0.18-0.58]) but mortality was doubled (30 [18%] vs 14 [8%] deaths; 2.39 [1.28-4.64]). The frequency of respiratory arrest was higher in the phenobarbital group than in the placebo group, and mortality was greatly increased in children who received phenobarbital plus three or more doses of diazepam (odds ratio 31.7 [1.2-814]).
                In children with cerebral malaria, phenobarbital 20 mg/kg provides highly effective seizure prophylaxis but is associated with an unacceptable increase in mortality. Use of this dose cannot, therefore, be recommended. While the parenteral iron-chelating agent desferrioxamine B has anti-malarial activity in humans, the usefulness of an orally active chelator for this indication has not been investigated previously in vivo. We conducted a prospective, double-blind, placebo-controlled, cross-over trial of deferiprone (L1; CP20; 1,2-dimethyl-3-hydroxypyridin-4-one) in 25 adult Zambians with asymptomatic Plasmodium falciparum parasitemia. Deferiprone was administered daily for three or four days in divided doses of 75 or 100 mg/kg of body weight, dosages that are effective for treating iron overload. No reduction in asexual intra-erythrocytic parasites was observed during or after deferiprone treatment. The mean peak plasma concentration of deferiprone (108.9 +/- 24.9 micromol/L) achieved was within the range demonstrated to inhibit the growth of P. falciparum in vitro, but the systemic exposure as determined by the 24-hr plasma concentration-time curve would not be predicted inhibit growth in vivo. No evidence of deferiprone-associated hematological toxicity was noted in this short-term study of these subjects, all of whom had clinical evidence of normal body iron stores. Because of the risk of neutropenia and other adverse effects with higher doses or prolonged use of the chelator, additional trials of deferiprone as a sole anti-malarial agent would not seem to be justified. In contrast, further efforts are needed to develop other orally active iron-chelating agents specifically for their anti-malarial action. Sixty-three patients with severe falciparum malaria were randomly administered one of the two regimens of a sequential combination of artesunate suppository followed by an oral mefloquine tablet. Thirty-two patients received artesunate suppositories (200 mg/capsule) given rectally at 0, 4, 8, 12, 24, 36, 48, and 60 hr (total = 1,600 mg: Group I). Thirty-one patients received the same artesunate suppositories given rectally at 0, 12, 24, 36, 48, and 60 hr (total = 1,200 mg: Group II). Both regimens were followed by two doses of oral mefloquine, 750 mg given at 72 hr and 500 mg at 84 hr. Patient baseline characteristics were comparable in the two groups. All patients were admitted for 28 days to the Bangkok Hospital for Tropical Diseases to assess efficacy, tolerability, and delayed neuropsychiatric effects. The mean [SD] parasite clearance time was significantly shorter in Group I than Group II (47.3 [12.4] hr versus 55.3 [17.4] hr; P = 0.05) and the rate of parasite reduction was significantly faster in Group I (P = 0.05, by log-rank test). Mean [SD] fever clearance times were similar in the two Groups (71.1 [41.2] hr and 76.9 [47.9] hr, respectively). Twenty-two patients with unrousable coma on admission (median Glasgow Coma Score = 9) regained consciousness after 1-4 days. No deaths occurred. Sixty of sixty-three patients were parasitologically and clinically cured within 3-4 days of treatment. Three patients (5%) with deteriorating conditions required rescue treatment (one patient in Group I was administered intravenous artesunate, and two patients in Group II required two extra doses of suppository). No patients had major adverse drug effects. The cure rates at 28 days of follow-up in Group I were 96% (26 of 27 patients) and 89% (24 of 27 patients) in Group II. Artesunate suppository followed by mefloquine was well tolerated and effective. In severe malaria, the sequential treatment is a suitable alternative treatment to parenteral drugs. Further studies in a larger number of patients under field conditions are required. The antiepileptic effect of lamotrigine (LTG) was assessed in a double-blind, placebo-controlled crossover trial in 24 adult patients with refractory partial seizures. LTG or placebo was added to existing antiepileptic drugs (AEDs). The dose of LTG varied from 75 to 400 mg daily. Three patients did not complete the trial. One was withdrawn from the trial with ataxia, tiredness, dyspnea, and diplopia while receiving LTG and died 18 days later of invasive carcinoma involving the liver. A second patient was withdrawn during baseline for contravening admission criteria, and a third received LTG in error during both treatment periods. Twenty-one patients (12 men and 9 women) completed the trial. An analysis of seizure counts in the 12-week treatment period with LTG showed a statistically significant reduction in seizures as compared with placebo for total seizures (p less than 0.002), partial seizures (p less than 0.002), and secondarily generalized seizures (p less than 0.05). The analysis of total seizure days showed a significant reduction during LTG treatment (p less than 0.002). There were no statistically significant changes in plasma concentrations of phenytoin (PHT), carbamazepine (CBZ), primidone (PRM), or phenobarbital (PB) between the two treatment periods. The most common adverse events reported during the trial were diplopia, drowsiness, tiredness, ataxia, and headache, but although these were more frequent during LTG treatment, the differences from placebo were not statistically significant. No hematological or biochemical changes were noted.
There are insufficient data to draw any conclusions for DFO and deferiprone. There are nonsignificant trends towards fewer seizures but overall harm (death) with DFO, and results from one small trial of deferiprone suggest shorter coma recovery and parasite clearance.
2008: We do not plan to update this review given the paucity of recent trials in this area and other priorities in malaria treatment research.