Efficacy of a Single Oral Dose of Artesunate plus Sulfalene-Pyrimethamineversus Praziquantel in the Treatment of Schistosoma mansoni in Kenyan Children: An Open-Label, Randomized, Exploratory Trial

Unlike praziquantel, artemisinin derivatives are effective against juvenile schistosome worms. We assessed the efficacy and safety of a single oral dose of artesunate plus sulfalene-pyrimethamine versus praziquantel in the treatment of Schistosoma mansoni. Seventy-three schoolchildren (aged 9-15 years) with confirmed S. mansoni infection in Rarieda, western Kenya, were randomly assigned to receive either a single oral dose of artesunate plus sulfalene-pyrimethamine (n = 39) or a single dose of praziquantel (n = 34). The cure and egg reduction rates at 4 weeks posttreatment were 69.4% (25/36) versus 80.6% (25/31) (P = 0.297) and 99.1% versus 97.5% (P = 0.607) in the artesunate plus sulfalene-pyrimethamine group versus praziquantel group, respectively. Fourteen children developed adverse events, and there were no serious adverse events. A single oral dose of artesunate plus sulfalene-pyrimethamine has efficacy comparable to that of praziquantel in the treatment of S. mansoni, but these results should be confirmed in larger randomized controlled trials.

Antimalarial artesunate-mefloquine versus praziquantel in African children with schistosomiasis: an open-label, randomized controlled trial

Schistosomiasis treatment entirely relies on a single drug, praziquantel, prompting research into alternative therapeutics. Here we evaluated the efficacy and safety of the antimalarial combination artesunate-mefloquine for the treatment of schistosomiasis in a proof-of-concept, pragmatic, open-label, randomized controlled trial in primary schools of six villages endemic for schistosomiasis in northern Senegal. Children (6-14 years) were eligible if Schistosoma eggs were detected by microscopy in urine and/or stool. In total, 726 children were randomized 1:1 to praziquantel (standard care: 40 mg kg-1 single dose; n = 364) or to artesunate-mefloquine (antimalarial dosage: artesunate 4 mg kg-1 and mefloquine 8 mg kg-1 daily for three consecutive days; n = 362). Eight children not meeting the inclusion criteria were excluded from efficacy analysis. Median age of the remaining 718 participants was 9 years; 399 (55.6%) were male, and 319 (44.4%) female; 99.3% were infected with Schistosoma haematobium and 15.2% with S. mansoni. Primary outcomes were cure rate, assessed by microscopy, and frequency of drug-related adverse effects of artesunate-mefloquine versus praziquantel at 4 weeks after treatment. Cure rate was 59.6% (208/349) in the artesunate-mefloquine arm versus 62.1% (211/340) in the praziquantel arm. The difference of -2.5% (95% confidence interval (CI) -9.8 to 4.8) met the predefined criteria of noninferiority (margin set at 10%). All drug-related adverse events were mild or moderate, and reported in 28/361 children receiving artesunate-mefloquine (7.8%; 95% CI 5.4 to 11.0) versus 8/363 (2.2%; 95% CI 1.1 to 4.3) receiving praziquantel (P < 0.001). Artesunate-mefloquine at antimalarial dosage was moderately safe and noninferior to standard-care praziquantel for the treatment of schistosomiasis, predominantly due to S. haematobium. Multicentric trials in different populations and epidemiological settings are needed to confirm these findings. ClinicalTrials.gov identifier: NCT03893097 .

SAFETY AND PHARMACOKINETICS OF PRAZIQUANTEL IN EUROPEAN POND TURTLES (EMYS ORBICULARIS)

Spirorchiidosis, caused by blood flukes of the genus Spirorchis, is a disease of great concern for the critically endangered European pond turtle (EPT; Emys orbicularis) in Switzerland. The endogenous life cycle of the parasite often leads to systemic inflammatory reactions, thrombosis, and death. Praziquantel (PZQ) is the treatment of choice against adult Spirorchis spp. in green (Chelonia mydas) and in loggerhead (Caretta caretta) sea turtles and is therefore considered for the treatment of EPT. This study aimed to establish a safe, easily applicable PZQ treatment for EPT, based on pharmacokinetics and tolerability. Three application methods were tested in a total of 12 adult EPT. Each turtle received a total of 75 mg/kg PZQ (three doses of 25 mg/kg in 3-h intervals [q3h × 3]) via IM (n = 3 turtles), SC (n = 3 turtles), or PO (n = 6 turtles) administration. Blood was collected 3, 6, 24, and 48 h after the first administration to determine the plasma concentration of PZQ using high-performance liquid chromatography coupled to mass spectrometry. Maximum measured R-PZQ concentrations (Cmax) were reached after 6 h. The mean Cmax of the total PZQ (sum of R- and S-PZQ) in the PO-treated EPT group was 1,929 ng/ml. Significantly higher concentrations were measured after IM and SC injection (mean Cmax of total PZQ = 12,715 ng/ml and 10,114 ng/ml, respectively). Transient side effects were evident after IM administration (local swelling and lameness), whereas no adverse drug effects were observed after PO and SC administration. Based on these results and the ease of administration to EPT, SC injection of PZQ at 25 mg/kg q3h times 3 serves as promising treatment application for the future.

SCHISTOACT: a protocol for an open-label, five-arm, non-inferiority, individually randomized controlled trial of the efficacy and safety of praziquantel plus artemisinin-based combinations in the treatment of Schistosoma mansoni infection

BACKGROUND

Schistosomiasis control relies on praziquantel for preventive chemotherapy. Alternative drugs are needed for the treatment and control of schistosomiasis. Praziquantel is effective against adult schistosome worms but ineffective against larval stages of the parasite and cannot prevent re-infection or interrupt the transmission of infection. Continued reliance on praziquantel for wide-scale schistosomiasis control will likely accelerate the emergence of drug resistance. Artemisinin derivatives are effective against the juvenile stages but ineffective against adult worms. The SCHISTOACT study aimed to evaluate the efficacy and safety of praziquantel plus one of four artemisinin-based combinations in treating Schistosoma mansoni infection in Kenya.

METHODS

The SCHISTOACT study is an open-label, head-to-head, five-arm, proof-of-concept, non-inferiority, individually randomized controlled trial with a follow-up of 12 weeks. A total of 540 primary school-aged children from the Mwea area, Kirinyaga County in central Kenya, diagnosed with S. mansoni infection (by Kato-Katz method) are randomly allocated (1:1:1:1:1) to a single dose of praziquantel plus a 3-day course of artesunate-sulfalene/pyrimethamine, or artesunate-amodiaquine, or artesunate plus mefloquine, or dihydroartemisinin-piperaquine, or praziquantel control arm. The primary endpoints are efficacy (cure rate, assessed by microscopy) and safety (adverse events) of each study arm 6 weeks after treatment. Secondary endpoints include cumulative cure rate, egg reduction rate, and re-infection 12 weeks after treatment. The non-inferiority margin is set at - 10 for the risk difference in cure rates between praziquantel and the combined treatment.

DISCUSSION

This study assesses a strategy for repurposing artemisinin-based combination therapies (ACTs) for treating schistosomiasis. It adopts a head-to-head comparison of four different ACTs to test a non-inferiority hypothesis and to strengthen local capacity to conduct clinical trials for interventions against neglected tropical diseases.

TRIAL REGISTRATION

Pan-African Clinical Trials Registry PACTR202001919442161 . Retrospectively registered on 6 January 2020.

Seroconversion following empiric praziquantel treatment as confirmatory diagnostic tool for chronic schistosomiasis

We report on six patients with suspected chronic schistosomiasis and negative microbiological findings at baseline. All patients were treated empirically with praziquantel and all seroconverted 20 days to two months after treatment. We suggest that seroconversion after praziquantel treatment may be used as a confirmatory diagnostic tool for chronic schistosomiasis.

Feasibility and safety of integrating mass drug administration for helminth control with seasonal malaria chemoprevention among Senegalese children: a randomized controlled, observer-blind trial

BACKGROUND

The overlap in the epidemiology of malaria and helminths has been identified as a potential area to exploit for the development of an integrated control strategy that may help to achieve elimination of malaria and helminths. A randomized, controlled, observer-blind trial was conducted to assess the feasibility and safety of combining mass drug administration (MDA) for schistosomiasis and soil transmitted helminths (STH) with seasonal malaria chemoprevention (SMC) among children living in Senegal.

METHODS

Female and male children aged 1-14 years were randomized 1:1:1, to receive Vitamin A and Zinc on Day 0, followed by SMC drugs (sulfadoxine-pyrimethamine and amodiaquine) on Days 1-3 (control group); or praziquantel and Vitamin A on Day 0, followed by SMC drugs on Days 1-3 (treatment group 1); or albendazole and praziquantel on Day 0, followed by SMC drugs on Days 1-3 (treatment group 2). Safety assessment was performed by collecting adverse events from all children for six subsequent days following administration of the study drugs. Pre- and post-intervention, blood samples were collected for determination of haemoglobin concentration, malaria microscopy, and PCR assays. Stool samples were analyzed using Kato-Katz, Merthiolate-iodine-formalin and PCR methods. Urine filtration, PCR and circulating cathodic antigen tests were also performed.

RESULTS

From 9 to 22 June 2022, 627 children aged 1-14 years were randomized into the three groups described above. Mild, transient vomiting was observed in 12.6% (26/206) of children in treatment group 2, in 10.6% (22/207) in group 1, and in 4.2% (9/214) in the control group (p = 0.005). Pre-intervention, the geometric mean value of Plasmodium falciparum parasite density was highest among children who received albendazole, praziquantel with SMC drugs. Post-intervention, the parasite density was highest among children who received SMC drugs only. Children who received praziquantel and SMC drugs had a lower risk of developing severe anaemia than their counterparts who received SMC drugs alone (OR = 0.81, 95% CI 0.13-5.00, p = 0.63).

CONCLUSIONS

Integration of MDA for helminths with SMC drugs was safe and feasible among Senegalese children. These findings support further evaluation of the integrated control model.

TRIAL REGISTRATION

The study is registered at Clinical Trial.gov NCT05354258.

Adverse drug effects among students following mass de-worming exercise involving administration of Praziquantel and Albendazole in KEEA Municipality, Ghana

Background

To manage the deleterious effects of parasitic infections such as lymphatic filariasis (LF) and schistosomiasis among school children, most countries including Ghana make use of mass drug administration (MDA). Although MDA has proven effective in reducing worm burden, unfortunately adverse drug effects (ADEs) post-MDA are derailing the gains and also remain poorly monitored. The study assessed incidence and factors associated with ADEs among students following a school-based mass de-worming exercise involving administration of Praziquantel (PZQT) and Albendazole (ADZ) against LF and SCH at Komenda-Edina-Eguafo-Abirem (KEEA) Municipal.

Methodology

After fulfilling all ethical obligations, a total of 598 students aged 5–20 years who received PZQT or ADZ monotherapy or a combination of the two (PZQT + ADZ) as part of the mass de-worming exercise were recruited through quota and random sampling. Bodyweight and height of students were measured and body mass index (BMI) calculated. Students were orally interviewed to obtain information such as age, sex, intake of diet before taking drugs. Subsequently, students were monitored over 24 hours post-MDA for cases of ADEs. Descriptive statistics and logistic regression analysis using SPSS version 26 was used to describe data collected and to determine associations between incidence of ADEs and predictor variables.

Principal findings

Out of the 598 students, 243 (40.64%) represented by 124 males (51.03%) and 119 females (48.97%) with mean (SD) age of 13.43 (2.74) years experienced one or more forms of ADE. In decreasing order, the detected ADEs included headache (64.6%), Abdominal pain (48.6%), fever (30.0%), diarrhea (21.4%) and itching (12.8%). Multivariable statistical analysis showed that age 5–9 years (OR: 2.01, p = 0.041) and underweight (OR: 2.02, p = 0.038) were associated with incidence of ADEs. Compared with students who received combination therapy, students who received ADZ only (OR: 0.05, p < 0.001) and PZQT only (OR: 0.26, p < 0.001) had low cases of ADEs. Gender and diet intake before MDA were not associated with ADE incidence.

Conclusion

ADE incidence was common among students in the KEEA municipality. Age, underweight, and double dosing were associated with increase in ADE incidence, while gender and food intake were not associated with increase in ADE incidence. The Disease Control Unit of the Ghana Health Service should incorporate stringent ADE monitoring in post-MDA surveillance in the National MDA program in order to be able to detect, manage and report ADEs to inform planning for future MDA programs. Such initiatives will help not only in improving effectiveness of MDA programs but also identify high risk groups and exact strategies to reduce negative influence of ADE on MDA coverage and anthelminthic drug compliance.

Efficacy and safety of praziquantel in the treatment of neurocysticercosis in Vietnam

Neurocysticercosis (NCC) is a parasitic infection of the nervous system and is responsible for considerable morbidity and mortality. Praziquantel (PZQ) is one of the antiparasitics mostly used in managing NCC, however, there have been only a few studies on the treatment outcome of this drug. The present study aimed to evaluate the efficacy and safety of PZQ in patients with NCC. Sixty patients with typical characteristics of NCC received three 10-day cycles of PZQ and the interruption between these cycles was 10 days. Additional treatment included antiinflammation (steroids), antiepileptics and analgesics. Clinical and imaging studies were done at baseline and six months after therapy to assess the efficacy of treatment. Laboratory evaluation was done before and after each cycle to investigate laboratory safety profiles. By six months after finishing therapy, all patients had clinical improvement and 75% of them were free of symptoms. The rates of complete, partial or no resolution of cysts on brain magnetic resonance imaging were 61.7%, 28.3% and 10% respectively. The efficacy of therapy was not associated with the number of cysts. There was no difference between the levels of aspartate aminotransferase, alanine aminotransferase, urea and creatinine before and after treatment. Conclusion: Praziquantel is effective and safe in the treatment of patients with neurocysticercosis.

Anthelmintics for people with neurocysticercosis

BACKGROUND

Neurocysticercosis is a parasitic infection of the central nervous system by the larval stage of the pork tapeworm and is a common cause of seizures and epilepsy in endemic areas. Anthelmintics (albendazole or praziquantel) may be given alongside supportive treatment (antiepileptics/analgesia) with the aim of killing these larvae (cysticerci), with or without corticosteroid treatment. However, there are potential adverse effects of these drugs, and the cysticerci may eventually die without directed anthelminthic treatment.

OBJECTIVES

To assess the effects of anthelmintics on people with neurocysticercosis.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, the WHO ICTRP, and ClinicalTrials.gov, up to 21 October 2020.

SELECTION CRITERIA

Randomized controlled trials comparing anthelmintics and supportive treatment (+/- corticosteroids) with supportive treatment alone (+/- corticosteroids) for people with neurocysticercosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the title and abstract of all articles identified by the search. We obtained full-text articles to confirm the eligibility of all studies that passed screening. One review author extracted data, which a second review author checked. Two review authors assessed the risk of bias of each trial and performed GRADE assessments. In cases of disagreement at consensus discussion stage between review authors, we consulted a third review author. We calculated risk ratios (RR) for dichotomous variables, with 95% confidence intervals (CIs) for pooled data from studies with similar interventions and outcomes.

MAIN RESULTS

We included 16 studies in the review. Only two studies investigated praziquantel and did not report data in a format that could contribute to meta-analysis. Most results in this review are therefore applicable to albendazole versus placebo or no anthelmintic. The aggregate analysis across all participants with neurocysticercosis did not demonstrate a difference between groups in seizure recurrence, but heterogeneity was marked (RR 0.94, 95% CI 0.78 to 1.14; 10 trials, 1054 participants; I² = 67%; low-certainty evidence). When stratified by participants with a single cyst or multiple cysts, pooled analysis suggests that albendazole probably improves seizure recurrence for participants with a single cyst (RR 0.61, 95% CI 0.4 to 0.91; 5 trials, 396 participants; moderate-certainty evidence). All studies contributing to this analysis recruited participants with non-viable, intraparenchymal cysts only, and most participants were children. We are uncertain whether or not albendazole reduces seizure recurrence in participants with multiple cysts, as the certainty of the evidence is very low, although the direction of effect is towards albendazole causing harm (RR 2.05, 95% CI 1.28 to 3.31; 2 trials, 321 participants; very low-certainty evidence). This analysis included a large study containing a highly heterogeneous population that received an assessment of unclear risk for multiple 'Risk of bias' domains. Regarding radiological outcomes, albendazole probably slightly improves the complete radiological clearance of lesions (RR 1.22, 95% CI 1.07 to 1.39; 13 trials, 1324 participants; moderate-certainty evidence) and the evolution of cysts (RR 1.27, 95% CI 1.10 to 1.47; 6 trials, 434 participants; moderate-certainty evidence). More adverse events appeared to be observed in participants treated with either albendazole or praziquantel compared to those receiving placebo or no anthelmintic. The most commonly reported side effects were headache, abdominal pain, and nausea/vomiting.

AUTHORS' CONCLUSIONS

For participants with a single cyst, there was less seizure recurrence in the albendazole group compared to the placebo/no anthelmintic group. The studies contributing to this evidence only recruited participants with a non-viable intraparenchymal cyst. We are uncertain whether albendazole reduces seizure recurrence for participants with multiple cysts. We also found that albendazole probably increases radiological clearance and evolution of lesions. There were very few studies reporting praziquantel outcomes, and these findings apply to albendazole only.

Safety evaluation of a novel topical combination of esafoxolaner, eprinomectin and praziquantel, in reproducing female cats

NexGard® Combo, a novel topical endectoparasiticide product for cats, is a combination of esafoxolaner, eprinomectin and praziquantel. The safety of this novel combination administered to females during reproduction and lactation was evaluated per analysis of breeding parameters and adverse reactions observed on females and offspring. Females with successful breeding history were randomized to three groups, a placebo group and groups treated with the novel formulation at 1× or 3× multiples of the maximum exposure dose. Females were dosed at 28-day intervals, at least twice before mating, then during a period including mating, pregnancy, whelping and 56 days of lactation. In the placebo, 1× and 3× groups, 10, 9 and 10 females, respectively completed the study (nine, seven and nine females achieved pregnancy), and were dosed 7.1 times on average. Breeding parameters included success of mating, success of gestation, length of gestation, abortion rate, number of live, dead and stillborn kittens at birth, number of kittens with abnormalities, weight of kittens after birth and at weaning, growth of kittens, proportion of male and female kittens, and proportion of kittens born alive and weaned. No significant adverse reactions related to the novel combination were observed on females and on kittens; no significant and adverse effects on breeding parameters were observed.

Target animal safety evaluation of a novel topical combination of esafoxolaner, eprinomectin and praziquantel for cats

The safety profile of NexGard® Combo, a novel topical product for cats combining esafoxolaner, eprinomectin and praziquantel, for the treatment and prevention of internal and external parasites, was evaluated in kittens, in two margin-of-safety studies (Studies #1 and #2), and in an oral tolerance study (Study #3). In the margin of safety studies, kittens were dosed several times topically with multiples of the maximum exposure dose (1×): in Study #1, 3× and 5× doses four times at 2-week intervals; in Study #2, 1×, 3× and 5× doses six times at 4-week intervals. In Study #3, kittens were dosed orally once with a 1× dose. Furthermore, in Study #1, another group of kittens was dosed topically twice at a 4-week interval with a formulation of esafoxolaner as the sole active ingredient dosed at 23×. Physical examinations and clinical pathology analyses were performed throughout the studies, followed by necropsy and detailed histopathological evaluation in Studies #1 and #2. No significant treatment related effects were observed in the three studies, except for one occurrence of reversible neurological signs attributed to eprinomectin in one cat after the third 5× dose in Study #2, with clinical signs observed nine hours after dosing, pronounced for a few hours, significantly improved the next day, and absent 2 days after dosing. In conclusion, NexGard® Combo was demonstrated safe in kittens following repeated topical administrations and following oral ingestion, and very high topical doses of esafoxolaner were well tolerated.

Factors affecting the uptake of preventive chemotherapy treatment for schistosomiasis in Sub-Saharan Africa: A systematic review

Background

Schistosomiasis affects nearly 220 million people worldwide, mainly in Sub-Saharan Africa (SSA). Preventive chemotherapy (PC) treatment, through regular mass-drug administration (MDA) of Praziquantel tablets remains the control measure of choice by Ministries of Health. Current guidelines recommend that 75% of school-aged children receive treatment. Many programmes, however, struggle to achieve this target. Given the risk of high reinfection rates, attaining sustained high levels of treatment coverage is essential. This study provides a comprehensive review of the barriers and facilitators operating at different levels of analysis, from the individual to the policy level, conditioning the uptake of PC for schistosomiasis in SSA.

Methodology/Principal findings

A systematic literature search was conducted in several databases for publications released between January 2002 and 2019 that examined factors conditioning the uptake of Praziquantel in the context of MDA campaigns in SSA. A total of 2,258 unique abstracts were identified, of which 65 were selected for full text review and 30 met all eligibility criteria. Joanna Briggs Institute’s Critical Appraisal and the Mixed-Methods Assessment tools were used to assess the strength of the evidence. This review was registered with PROSPERO (CRD42017058525).

A meta-synthesis approach was used. Results indicated publication bias, with the literature focusing on East African rural settings and evidence at the individual and programmatic levels. The main influencing factors identified included material wellbeing, drug properties, knowledge and attitudes towards schistosomiasis and MDAs, fears of side effects, gender values, community and health systems support, alongside programme design features, like training, sensitisation, and provision of incentives for drug-distributors. The effect of these factors on determining Praziquantel uptake were explored in detail.

Conclusions/Significance

Multiple determinants of treatment uptake were found in each level of analysis examined. Some of them interact with each other, thus affecting outcomes directly and indirectly. The promotion of context-based transdisciplinary research on the complex dynamics of treatment uptake is not only desirable, but essential, to design effective strategies to attain high levels of treatment coverage.

Schistosomiasis is a parasitic infection that affects nearly 220 million people worldwide. Long-term effects include anaemia, growth stunting, bladder cancer and infertility. Currently, the main approach to schistosomiasis control involves mass preventive chemotherapy treatment. Current guidelines recommend treating 75% of school-aged children but many programmes struggle to achieve this target. This study conducted a comprehensive review of factors conditioning the uptake of treatment in Sub-Saharan Africa across different levels of analysis: individual, interpersonal, organisational, community and policy. This examination showed, first, that the literature suffers of publication bias, with most studies based in rural East African sites and focusing in discussing individual- and policy-level factors. It indicated as well that people’s livelihoods, food security, and school-enrolment, alongside knowledge and attitudinal factors influenced treatment uptake at the individual level. Various contextual factors concerning interpersonal relations, organisations’ resources, and prevalent socio-cultural features (e.g., gender) further shaped people’s responses to MDA campaigns. Finally, it was observed that the effectiveness of programme-level decisions on sensitisation, training, and drug-delivery strategies were constantly re-shaped by mediating factors operating at lower levels of analysis. We conclude that the promotion of context-based transdisciplinary research is essential to design effective strategies to promote sustainable high levels of treatment coverage.

Efficacy and safety of praziquantel and dihydroartemisinin piperaquine combination for treatment and control of intestinal schistosomiasis: A randomized, non-inferiority clinical trial

BACKGROUND

Despite the reported success in reducing morbidity, praziquantel alone is insufficient for the control and elimination of schistosomiasis, partly due to its poor efficacy against the juvenile worms. Artemisinin derivatives are effective against juvenile worms but are less effective against adult worms. We compared the safety and efficacy of praziquantel and Dihydroartemisinin-piperaquine combination against the standard praziquantel alone for treatment of intestinal schistosomiasis.

METHODS

In this randomized, open-label, non-inferiority trial, 639 Schistosoma mansoni infected children were enrolled and randomized to receive either praziquantel alone or praziquantel plus Dihydroartemisinin-piperaquine combination. Two stool samples were collected on consecutive days at baseline, 3 and 8 weeks post-treatment and analyzed using thick smear Kato Katz method. Efficacy was assessed by cure and egg reduction rates at 3 and 8 weeks post-treatment. Adverse events were assessed within four hours of drugs intake. The primary outcome was cure rates at 8 weeks of post-treatment. Secondary outcomes were egg reduction rates at 8 weeks of post-treatment and treatment-associated adverse events.

RESULTS

At 3 weeks of post-treatment, cure rates were 88.3% (263/298, 95% CI = 84.1%- 91.4%) and 81.2% (277/341, 95% CI = 76.7%- 85.0%) for the combination therapy and praziquantel alone, respectively (p < 0.01, odds ratio (OR) = 1.74, 95% CI of OR = 1.11 to 2.69). At 8 weeks, there was a significant drop in the cure rates in praziquantel alone group to 63.9% (218/341, 95% CI = 58.7%- 68.8%) compared to 81.9% (244/298, 95% CI = 77.1%- 85.8%) in the combination therapy group (p < 0.0001, OR = 2.55, 95%CI of OR = 1.75 to 3.69). Egg reduction rates at 8 weeks post-treatment were significantly higher in the combination therapy group 93.6% (95% CI = 90.8%- 96.4%) compared to 87.9% (95% CI = 84.4%- 91.4%) in the praziquantel only group (p = 0.01). On both Univariate and Multivariate regression analysis, type of treatment received was a significant predictor of cure at week 8 post-treatment. Overall, 30.8% (95% CI = 27.2%- 34.4%) of the study participants experienced mild and transient treatment-associated adverse events, post-treatment abdominal pain (27.1%) being the most common adverse event observed. There was no significant difference in the overall occurrence of adverse events between the two treatment groups.

CONCLUSION

Praziquantel and Dihydroartemisinin piperaquine combination therapy is safe, and more efficacious compared to praziquantel alone for the treatment of intestinal schistosomiasis. Further studies are needed to explore if the combination therapy can be considered as an option for mass drug administration to control and eventually eliminate schistosomiasis.

Comparison of praziquantel efficacy at 40 mg/kg and 60 mg/kg in treating Schistosoma haematobium infection among schoolchildren in the Ingwavuma area, KwaZulu-Natal, South Africa

BACKGROUND

The World Health Organization recommends praziquantel (PZQ) (40 mg/kg body weight) for treating schistosomiasis. However, drug failure has been reported, prompting use of 60 mg/kg, for which results have been inconsistent.

OBJECTIVES

To compare the efficacy of PZQ 40 mg/kg and 60 mg/kg in treating schoolchildren infected with Schistosoma haematobium.

METHODS

The study was conducted during November 2017 - August 2018 in the Ingwavuma area, uMkhanyakude District, KwaZulu-Natal Province, South Africa. Children aged 10 - 15 years were screened for S. haematobium using a filtration technique. Infected children were randomly assigned to a dose of PZQ of 40 mg/kg or 60 mg/kg. Side-effects were recorded within 24 hours after treatment using questionnaires and direct observation. Four weeks after treatment, participants were retested for S. haematobium infection. Baseline and post-treatment mean egg counts were calculated. Cure rate (CR) and egg reduction rate (ERR) were used to determine PZQ efficacy, while repeated-measures analysis of variance determined the effect of both doses on infection intensity. A χ2 test was used to determine the association of side-effects with treatment, with a p-value ≤0.05.

RESULTS

Forty-three and 36 children were treated with PZQ 40 mg/kg and 60 mg/kg, respectively. The 40 mg/kg group had a CR of 79.0% and an ERR of 97.2%, and the 60 mg/kg group a CR of 83.0% and an ERR of 98.3%. The effect of dose on infection intensity was not significantly different between the two groups (p&gt;0.05). Abdominal pains, dizziness and fatigue were common among children who received PZQ 40 mg/kg, while headache, dizziness and nausea were common in the 60 mg/kg group.

CONCLUSIONS

The efficacy of PZQ at 60 mg/kg was similar to that at 40 mg/kg. A dose &gt;40 mg/kg therefore does not add value in treating S. haematobium infection. Transient side-effects (mostly dizziness) were observed more in the 60 mg/kg group than in the 40 mg/kg group. We recommend continued use of 40 mg/kg body weight for treating schistosomiasis.

Efficacy and safety of single-dose 40 mg/kg oral praziquantel in the treatment of schistosomiasis in preschool-age versus school-age children: An individual participant data meta-analysis

BACKGROUND

Better knowledge of the efficacy and safety of single-dose 40 mg/kg oral praziquantel in preschool-age children is required, should preventive chemotherapy programs for schistosomiasis be expanded to include this age group.

METHODOLOGY

We analyzed individual participant-level data from 16 studies (13 single-arm or cohort studies and three randomized trials), amounting to 683 preschool-age children (aged <6 years) and 2,010 school-age children (aged 6-14 years). Children had a documented Schistosoma mansoni or S. haematobium infection, were treated with single 40 mg/kg oral praziquantel, and assessed between 21 and 60 days post-treatment. Efficacy was expressed as arithmetic mean and individual egg reduction rate (ERR) and meta-analyzed using general linear models and mixed models. Safety was summarized using reported adverse events (AEs).

PRINCIPAL FINDINGS

Preschool-age children had significantly lower baseline Schistosoma egg counts and more losses to follow-up compared to school-age children. No difference in efficacy was found between preschool- and school-age children using a general linear model of individual-participant ERR with baseline log-transformed egg count as covariate and study, age, and sex as fixed variables, and a mixed model with a random effect on the study. Safety was reported in only four studies (n = 1,128 individuals); few AEs were reported in preschool-age children 4 and 24 hours post-treatment as well as at follow-up. Three severe but not serious AEs were recorded in school-age children during follow-up.

CONCLUSIONS/SIGNIFICANCE

There is no indication that single-dose 40 mg/kg oral praziquantel would be less efficacious and less safe in preschool-age children compared to school-age children, with the caveat that only few randomized comparisons exist between the two age groups. Preventive chemotherapy might therefore be extended to preschool-age children, with proper monitoring of its efficacy and safety.

Praziquantel and risk of visual disorders: Case series assessment

Introduction

Praziquantel has been in use by helminthiasis and schistosomiasis control programs for about 30 years. Although deemed to be safe with regard to its adverse drug reaction profile in reference to the product information of Biltricide, the Eritrean Pharmacovigilance Center received reports of visual abnormalities related to the drug. This is a case series assessment of unusual cases of visual abnormalities associated with praziquantel.

Methods

Search was made in VigiBase by setting praziquantel as a drug substance, Eritrea as the reporting country and all eye disorders, high level term (HLT) to capture all visual disorders associated with Praziquantel. The retrieved dataset was exported into an Excel spreadsheet for descriptive analysis and causality was assessed using Austin Bradford-Hill criteria.

Results

There are a total of 2579 Individual Case Safety Reports (ICSRs) of various Adverse Drug Reactions (ADRs) of praziquantel reported from Eritrea in VigiBase. The 61 reports of visual abnormalities that arose within the first 24 hours of praziquantel administration are of note. With a strong association as evidenced by the positive IC₀₂₅ value, the association of praziquantel and blurred vision was consistently reported from different health facilities over a period of three years. It is a specific association in terms of both the exposure (only praziquantel) and the outcome (blurred vision) as reported in majority of the cases. However, experimental evidences for the association are lacking, the underweight profile of the Eritrean population suggests overdosing as a possible risk factor for the occurrence of these reactions.

Conclusion

The strength, temporal plausibility, consistency and specificity of the association are suggestive of a causal association between praziquantel and visual disorders.

The Eritrean Pharmacovigilance centre, since its integration in Mass Drug Administration in 2017, has been receiving large proportion of reports of adverse drug reactions associated with the drug praziquantel administered in mass drug campaigns. Of note were reports of the visual abnormalities namely blurred vision and visual impairment which are not known to be related to the drug. On a probability assessment, the series of 61 cases seems to show a reasonable link between the reported adverse reactions and praziquantel but not an absolute cause and effect relationship. This study suggests inaccuracies in the dose of praziquantel, in reference to some African studies, as a possible root cause, that might have led to overdosing of some subjects and hence the occurrence of the reported reactions in noticeable rates. It also addresses primarily a public health issue, rendering the findings interesting to both the scientific and non-scientific communities in general and disease control programs in particular. It is a driving force to conduct further research, improve our understanding of praziquantel and its safety profile, and the use of the drug in better ways.

A randomized, blinded, controlled, multi-centered field study assessing the treatment of gastrointestinal nematode infections in cats with fluralaner plus moxidectin spot-on solution (Bravecto® Plus)

BACKGROUND

A spot-on formulation containing fluralaner (280 mg/ml) plus moxidectin (14 mg/ml) (Bravecto® Plus) was developed for the treatment of nematode infections as well as providing 12 weeks of protection against insect and acarine parasites in cats. The effectiveness and safety of this product against feline gastrointestinal nematodes was assessed in naturally-infested, client-owned cats under field conditions in Albania, Bulgaria, Germany and Hungary.

METHODS

To be eligible for enrollment in this investigator-blinded study cats had to be at least 10 weeks-old, weigh at least 1.2 kg, be clinically healthy, and have a faecal sample testing positive for nematodes no more than eight days prior to treatment. Cats were stratified into blocks of three in order of presentation at each center and randomly allocated in a 2:1 ratio to be treated topically on Day 0 with fluralaner plus moxidectin (minimum dose rates 40 mg/kg and 2 mg/kg, respectively) or emodepside plus praziquantel (minimum dose rates 3 mg/kg and 12 mg/kg, respectively) (Profender®). Faecal samples were collected from cats prior to treatment and 14 ± 4 days later.

RESULTS

There were 182 cats randomized to the fluralaner plus moxidectin group, and 91 to the emodepside plus praziquantel group. Prior to treatment the most commonly identified nematode egg was Toxocara cati, found in 79.1 and 82.4% of cats in the fluralaner plus moxidectin and emodepside plus praziquantel groups, respectively. Eggs of Toxascaris leonina were found in 8.2 and 6.6% of cats; of hookworms in 30.8 and 24.2%; and of Capillaria spp. in 7.1 and 4.3%, respectively. After treatment, faecal samples from 98.3% of fluralaner plus moxidectin treated and 96.6% of emodepside plus praziquantel-treated cats were free of nematode ova. Geometric mean faecal egg count reductions for T. cati, the only eggs found in post-treatment faecal samples, were 99.97% and 99.93%, respectively. Treatment with fluralaner plus moxidectin was non-inferior to emodepside plus praziquantel. Both products were safe and well tolerated by cats treated under field conditions.

CONCLUSIONS

This field study confirms that, in addition to 12-week extended duration flea and tick control, fluralaner plus moxidectin provides broad spectrum treatment of nematodes in cats.

Safety of topical administration of fluralaner plus moxidectin concurrently with praziquantel in cats

BACKGROUND

Fluralaner provides efficacy against feline ectoparasites following topical administration. Moxidectin is routinely used to treat gastrointestinal nematode infections and prevent heartworm disease caused by Dirofilaria immitis. Praziquantel is routinely used to treat feline tapeworm infections. The safety of a fluralaner plus moxidectin combination topical solution (Bravecto™ Plus, MSD Animal Health) was assessed when administered concurrently with a commercially available praziquantel topical solution (Droncit™ Spot-on, Bayer Animal Health GmbH). The highest dose rates in clinical use were tested.

RESULTS

Concurrent topical administration of a fluralaner plus moxidectin and a praziquantel product did not result in adverse findings. One out of ten cats receiving praziquantel only (control group), and two out of ten cats receiving fluralaner plus moxidectin and praziquantel (treatment group) had dandruff-like flakes in their coat at the application site. Two out of the ten control cats and three cats out of the ten treatment group cats had very small amounts of unidentified material (minute crusts or crumbs) at the application site which was only visible during close inspection.

CONCLUSIONS

The concurrent treatment of cats with fluralaner plus moxidectin and praziquantel at the maximum dose in clinical use was well tolerated.

Safety, efficacy and acceptability of praziquantel in the treatment of Schistosoma haematobium in pre-school children of Kwale County, Kenya

Background

The recommended strategy for control of schistosomiasis is preventive chemotherapy with praziquantel (PZQ). Pre-school children (PSC) are excluded from population treatment programs. In high endemic areas, these children are also at risk, and require treatment with PZQ. The Government of Kenya initiated the National School-Based Deworming Programme (NSBDP) where PSC in Early Childhood Development Education (ECDE) Centers are only eligible for treatment with albendazole (ABZ) but not with PZQ.

Methodology/Principal findings

400 PSC were enrolled, from 10 randomly selected ECDE Centers in Kwale County, Kenya where children were treated with crushed PZQ tablets mixed with orange juice, at a single dose of 40 mg/kg. Adverse events were assessed 24 hours post-treatment through questionnaires administered to the parents or guardians. Acceptability was determined by observing if the child spat and/ or vomited all or part of the PZQ dose immediately after treatment. Efficacy was assessed by examining urine samples for Schistosoma haematobium eggs in the 5 weeks post-treatment follow-up. Children testing negative for S. haematobium during the follow-up were considered cured. Egg reduction rate (ERR) was calculated as the decrement in the infection intensity (group’s geometric mean egg counts per 10 ml of urine) following treatment expressed as a proportion of the pre-treatment infection intensity. Before treatment, 80 out of the 400 children enrolled in the study tested positive for S. haematobium (20.0% (95% confidence interval (CI) 16.4–24.2%). Of these, 41 had infections of heavy intensity (51.3%) while the rest (48.7%) were of light intensity. Five weeks post-treatment, 10 children who had heavy intensity infection were diagnosed with S. haematobium (prevalence: 2.5% (95% CI 1.5–4.9%). Infection intensities decreased significantly from 45.9 (95% CI: 31.0–68.0) eggs/ 10 ml urine to1.4 (95% CI: 1.1–1.7) eggs/ 10 ml urine during pre-and post-treatment respectively. The ERR was 96.9%. There were no severe adverse events during follow up 24 hours post treatment. Treatment tolerability among the 400 children was high as none of the children spat and/ or vomited as observed in this study.

Conclusion/Significance

The study revealed that crushed PZQ is safe and effective in the treatment of urogenital schistosomiasis in this age group. It is therefore recommended that PZQ should be administered to the PSC in Kwale County.

Control of schistosome infections is through treatment of infected people with a single dose of the anti-helminth drug praziquantel (PZQ) which is safe, highly efficacious, and can reverse schistosome-related morbidity particularly in the early stages of disease progression. However pre-school children are normally excluded due to the belief that these children are not sufficiently exposed to infective water to experience high infection rates. This could lead to clinical manifestation of the disease and the lack of safety data on praziquantel in this age group. Due to this we investigated the safety, efficacy and acceptability of praziquantel in Kwale County, Kenya. We examined urine samples from 400 preschool children. They were treated with crushed praziquantel (40mg/kg) mixed with orange juice and the efficacy of the treatment was determined 5 weeks after treatment. Acceptability was determined by whether the child spat and/ or vomited the treatment through the direct observed treatment (DOT).No child spat or vomited during treatment. Safety of the treatment was assessed by interviewing the parents of the treated children for adverse events (e.g., abdominal pain, dizziness, and headache). The treatment was well tolerated and most of the parasites were cleared by praziquantel.

Suspected adverse reactions to oral administration of a praziquantel-pyrantel combination in captive cheetahs (Acinonyx jubatus)

OBJECTIVE To characterize adverse reactions to oral administration of a combination of praziquantel and pyrantel embonate or pyrantel pamoate, with or without oxantel embonate, in captive cheetahs (Acinonyx jubatus). DESIGN Retrospective case series and case-control study. ANIMALS 16 captive cheetahs with signs of adverse reaction to oral administration of praziquantel and pyrantel, with or without oxantel embonate (affected group), and 27 cheetahs without such reactions (unaffected group), all from 3 independent facilities. PROCEDURES Medical records and postmortem findings for affected cheetahs were reviewed and compared with those of unaffected animals. Anthelmintic doses administered, age, and sex of cheetahs were compared between groups. RESULTS 3 reactions in affected cheetahs were fatal, whereas the remainder ranged from mild to severe. Postmortem examination failed to reveal any disease processes or conditions to explain the deaths. No differences in anthelmintic dose were identified between affected and unaffected cheetahs for all facilities combined, and no correlation existed between dose and reaction severity. No association with sex was detected, but affected cheetahs were significantly younger than unaffected cheetahs. This difference was not significant after controlling for facility. CONCLUSIONS AND CLINICAL RELEVANCE Cheetahs were concluded to have had an adverse reaction to the praziquantel-pyrantel combination because of temporal proximity of onset of clinical signs to dose administration, similarity of signs to those reported for toxicosis in other species for these drugs, and a lack of other disease process or environmental explanatory factors. A highly cautious approach to the use of this drug combination is recommended for cheetahs.

Ultrasonographic evaluation of urinary tract morbidity in school-aged and preschool-aged children infected with Schistosoma haematobium and its evolution after praziquantel treatment: A randomized controlled trial

Background

Schistosoma haematobium infections are responsible for significant urinary tract (UT) complications. Schistosomiasis control programs aim to reduce morbidity, yet the extent of morbidity in preschool-aged children and the impact of treatment on morbidity reduction are not well studied.

Methodology

Our study was embedded in a randomized, placebo-controlled, single-blind trial in Côte d’Ivoire, which evaluated the efficacy and safety of three doses (20, 40 and 60 mg/kg) of praziquantel in school-aged (SAC) and preschool-aged (PSAC) children infected with S. haematobium. Enrolled children were invited to participate in an ultrasound examination prior and six months after treatment. At these time points 3 urine samples were collected for parasitological and clinical examinations.

Principal findings

162 PSAC and 141 SAC participated in the ultrasound examination at baseline, of which 128 PSAC and 122 SAC were present at follow-up. At baseline 43% (70/162) of PSAC had UT morbidity, mostly at bladder level and 7% had hydronephrosis. 67% (94/141) of SAC revealed mainly moderate UT pathology, 4% presented pseudopolyps on the bladder wall, and 6% had pyelectasis. At follow up, 45% of PSAC and 58% of SAC were S. haematobium positive, mostly harboring light infection intensities (41% and 51%, respectively). Microhematuria was present in 33% of PSAC and 42% of SAC and leukocyturia in 53% and 40% of PSAC and SAC, respectively. 50% (64/128) of PSAC and 58% (71/122) of SAC presented urinary tract morbidity, which was mainly mild. A significant correlation (p<0.05) was observed between praziquantel treatment and reversal of S. haematobium induced morbidity. Progression of UT pathology decreased with increasing praziquantel dosages. A worsening of morbidity was observed among children in the placebo group.

Conclusion/Significance

Bladder morbidity is widespread among PSAC. Praziquantel treatment is significantly associated with the reversal of S. haematobium induced morbidity, which underscores the importance of preventive chemotherapy programs. These programs should be expanded to PSAC to prevent or decrease the prevalence of morbidity in young children. This trial is registered as an International Standard Randomized Controlled Trial, number ISRCTN15280205.

Schistosoma haematobium is a parasite that infects the human genito-urinary tract. People get infected with the parasite through contact with fresh water and children are at major risk. The complications linked to this infection are due to an inflammation caused by accumulation of the eggs in peri-bladder veins. If not treated, infections can last years and different degrees of severity are observed. These range from thickening of the bladder wall and blurriness of the mucosa to more serious lesions such as pseudo polyps and masses in the bladder that can, with time, evolve in cancer of the bladder. We analyzed preschool-aged children (PSAC) and school-aged children (SAC) with ultrasound before and after praziquantel treatment. Children were randomly assigned to different doses of praziquantel (20, 40 or 60 mg/kg) or to placebo at baseline. Six months after treatment all children underwent another ultrasound of the urinary tract. We included 162 PSAC and 141 SAC at baseline, of which 128 PSAC and 122 SAC had a second ultrasound evaluation six months afterwards. In addition, urine was sampled at both time points for presence of blood, proteins and signs of infection (leukocytes and nitrates). Six months post-treatment 45% of PSAC and 58% of SAC were S. haematobium positive. Already at the first screening 43% of PSAC and 67% of SAC had bladder lesions. After treatment 50% of PSAC and 58% of SAC still had pathology linked to the infection. We found a correlation between the treatment dose and healing of bladder lesions. On the other hand, we experienced an aggravation of lesions in the placebo group. Praziquantel is given to SAC as preventive chemotherapy every year at national level, where this parasite is endemic. This program should be expanded and include PSAC as well in order to reduce the consequences of infection.

Efficacy and safety of praziquantel 40 mg/kg in preschool-aged and school-aged children: a meta-analysis

BACKGROUND

Children carry most of the schistosomiasis burden. While school-aged children are the principal target group of preventive chemotherapy with praziquantel, limited information on efficacy and safety exists for preschool-aged children.

METHODS

Here, we conducted a meta-analysis of clinical trials of praziquantel for treating children with any form of schistosomiasis. Efficacy was reported as cure rate (CR) and egg reduction rates (ERR); statistical corrections were applied based on methodological disparities across trials to derive the predicted geometrical mean ERR (pERRgm). Safety was reported as frequencies of adverse events.

RESULTS

Forty-seven comparative and non-comparative studies were identified, enrolling 15,549 children of whom 14,340 (92%) were assessed between 3 and 8 weeks post-treatment with praziquantel 40 mg/kg (the WHO-recommended treatment, n = 8,380, 56%) or comparators (n = 5,960, 44%). The median age was 10 years (range 1-19), 11% (n = 1,694) were preschool-aged. The CR and pERRgm with praziquantel 40 mg/kg were respectively: S. haematobium, 73.6% (95% CI: 63.5-81.40, 25 study arms) and 94.7% (95% CI: 92.7-96.4); S. mansoni, 76.4% (95% CI: 71.5-81.0, 34 arms) and 95.3% (95% CI: 94.2-96.2); S. mansoni/S. haematobium, 67.6% (95% CI: 54.1-80.7, 5 arms) and 93.4% (95% CI: 89.9-96.2); S. japonicum, 94.7% (95% CI: 92.2-98.0) and 98.7% (95% CI: 98.3-99.2). Mixed-effect multivariate analysis found no significant difference between preschool- and school-aged children for CR or pERRgm in S. haematobium (P = 0.309 and P = 0.490, respectively) or S. mansoni (P = 0.982 and P = 0.895) after controlling for time of assessment, formulation, intensity of infection and detection method. Praziquantel was reportedly safe at all ages, with only mild reported adverse events which cleared rapidly after treatment.

CONCLUSIONS

Praziquantel 40 mg/kg was effective at reducing infection intensity in all Schistosoma species without differences between preschool- and school-aged children. However, conclusions should be tempered because of the limited number of preschool-aged children enrolled, disparities in study procedures and limited information made available in publications, as well as the current imperfect test-of-cure. Also, although reportedly well-tolerated, safety was inconsistently assessed. Studies in target groups, individual-data meta-analysis and standardised methodologies are needed for more robust evidence-base.

Efficacy and Safety of Moxidectin, Synriam, Synriam-Praziquantel versus Praziquantel against Schistosoma haematobium and S. mansoni Infections: A Randomized, Exploratory Phase 2 Trial

Background

Schistosomiasis affects millions of people, yet treatment options are limited. The antimalarial Synriam (piperaquine 150 mg/arterolane 750 mg) and the anthelminthic moxidectin revealed promising antischistosomal properties in preclinical or clinical studies.

Methodology

We conducted two single-blind, randomized exploratory Phase 2 trials in Schistosoma mansoni and S. haematobium-infected adolescents in northern and central Côte d’Ivoire. Our primary endpoints were cure rates (CRs) and egg reduction rates (ERRs) based on geometric mean and safety. Each subject was asked to provide two stool samples (S. mansoni trial) for Kato-Katz analysis or three urine samples (S. haematobium trial) for urine filtration and one finger prick for malaria screening at baseline and follow-up. Participants were randomly assigned to either moxidectin, Synriam, Synriam plus praziquantel or praziquantel.

Principal Findings

128 adolescents (age: 12–17 years) were included in each study. Against S. haematobium moxidectin and Synriam revealed low efficacy. On the other hand, Synriam plus praziquantel and praziquantel yielded CRs of 60.0% and 38.5% and ERRs of 96.0% and 93.5%, respectively. CRs observed in the treatment of S. mansoni were 13.0%, 6.7%, 27.0%, and 27.6% for moxidectin, Synriam, Synriam plus praziquantel and praziquantel, respectively. ERRs ranged from 64.9% (Synriam) to 87.5% (praziquantel).

Conclusion/Significance

Synriam and moxidectin show low efficacy against S. haematobium, hence an ancillary benefit is not expected when these drugs are used for treating onchocerciasis and malaria in co-endemic settings. Further studies are needed to corroborate our findings that moxidectin and Synriam show moderate ERRs against S. mansoni.

Schistosomiasis is a parasitic infection that affects millions of people all over the world and it is due to schistosomes, helminths (worms) that infect the intestine and the urinary bladder. Treatment options are limited, with praziquantel being the only used drug. The antimalarial Synriam and the anthelminthic moxidectin revealed good action against this worm in previous studies. We conducted two studies in Schistosoma mansoni and S. haematobium-infected adolescents in Côte d’Ivoire. Subjects positive for the infection were allocated by chance to the four groups of treatment (moxidectin, Synriam, Synriam plus praziquantel or praziquantel); participants did not know which drug they took. Our aim was to calculate how many participants were negative after the treatment and how did the intensity of infection change before and after treatment. Each subject provided stools and urines for examination. 128 adolescents were included in each study. Moxidectin and Synriam did not work well against S. haematobium. Against S. mansoni, only a small part of the participants were negative after treatment in all treatment groups, but the intensity of infections were reduced. Further studies are needed to better understand this result.

Efficacy and safety of praziquantel for the treatment of human schistosomiasis during pregnancy: a phase 2, randomised, double-blind, placebo-controlled trial

BACKGROUND

Despite WHO recommendations to offer pregnant women treatment with praziquantel, many nations continue to withhold treatment, awaiting data from controlled trials addressing safety and efficacy. The objectives of this study were to assess whether treatment of pregnant women with schistosomiasis at 12-16 weeks gestation leads to improved maternal and newborn outcomes and to collect maternal and newborn safety data.

METHODS

This phase 2, randomised, double-blind, placebo-controlled trial was done in 72 baranguays (villages) serviced by six municipal health centres in a schistosomiasis endemic region of northeastern Leyte, Philippines. Pregnant women (at 12-16 weeks gestation) who were otherwise healthy but infected with Schistosoma japonicum were enrolled and randomly assigned (1:1) to receive either over-encapsulated praziquantel (total dose 60 mg/kg given as two split doses) or placebo. Participants, investigators, midwives, and laboratory staff were all masked to treatment. The primary outcome was birthweight. Safety data were collected including immediate reactogenicity, post-dosing toxicology ascertained 24 h after study drug administration, and maternal and newborn serious adverse events. Analysis followed the intention-to-treat principle. Analyses were done using hierarchical generalised linear models to adjust for identified confounders and account for potential clustering of observations within villages and municipalities. This trial is registered with ClinicalTrials.gov, number NCT00486863.

FINDINGS

Between Aug 13, 2007, and Dec 3, 2012, 370 pregnant women were enrolled and randomly assigned to each treatment group (184 to the placebo group, 186 to the praziquantel group). Most women had low-intensity infections (n=334, 90%). Treatment with praziquantel did not have a significant effect on birthweight (2·85 kg in both groups, β=-0·002 [95% CI -0·088 to 0·083]; p=0·962). Treatment was well tolerated with reactogenicity rates similar to those seen in non-pregnant participants (severe reactions occurred in five patients in the praziquantel group and two in the placebo group, and included headache, fever, and malaise). There were no significant differences in key safety outcomes including abortion, fetal death in utero, and congenital anomalies.

INTERPRETATION

Results from this study provide important data from a controlled trial in support of the expansion of treatment policies to include pregnant women as recommended by WHO.

FUNDING

National Institutes of Health, National Institute of Allergy and Infectious Diseases (U01AI066050).

Inflammation Caused by Praziquantel Treatment Depends on the Location of the Taenia solium Cysticercus in Porcine Neurocysticercosis

Background

Neurocysticercosis (NCC), infection of the central nervous system by Taenia solium cysticerci, is a pleomorphic disease. Inflammation around cysticerci is the major cause of disease but is variably present. One factor modulating the inflammatory responses may be the location and characteristics of the brain tissue adjacent to cysticerci. We analyzed and compared the inflammatory responses to cysticerci located in the parenchyma to those in the meninges or cysticerci partially in contact with both the parenchyma and the meninges (corticomeningeal).

Methodology/Principal Findings

Histological specimens of brain cysticerci (n = 196) from 11 pigs naturally infected with Taenia solium cysticerci were used. Four pigs were sacrificed after 2 days and four after 5 days of a single dose of praziquantel; 3 pigs did not receive treatment. All pigs were intravenously injected with Evans Blue to assess disruption of the blood-brain barrier. The degree of inflammation was estimated by use of a histological score (ISC) based on the extent of the inflammation in the pericystic areas as assessed in an image composed of several photomicrographs taken at 40X amplification. Parenchymal cysticerci provoked a significantly greater level of pericystic inflammation (higher ISC) after antiparasitic treatment compared to meningeal and corticomeningeal cysticerci. ISC of meningeal cysticerci was not significantly affected by treatment. In corticomeningeal cysticerci, the increase in ISC score was correlated to the extent of the cysticercus adjacent to the brain parenchyma. Disruption of the blood-brain barrier was associated with treatment only in parenchymal tissue.

Significance

Inflammatory response to cysticerci located in the meninges was significantly decreased compared to parenchymal cysticerci. The suboptimal inflammatory response to cysticidal drugs may be the reason subarachnoid NCC is generally refractory to treatment compared to parenchymal NCC.

The cystic larvae of the pork tapeworm Taenia solium may affect the human brain causing neurocysticercosis (NCC), a very frequent cause of neurological symptoms in developing countries. The clinical expression and response to treatment of human NCC are related to the location of cysticerci inside (intraparenchymal) or outside the brain parenchyma (extraparenchymal NCC). We used a naturally infected pig model to assess the characteristics of inflammation around brain cysticerci of parenchymal, meningeal and mixed locations. There were no major differences in inflammation without treatment. After antiparasitic treatment with praziquantel, inflammation around parenchymal brain cysticerci increased in comparison to meningeal located cysticerci. Cysticerci partially surrounded by both brain parenchyma and meninges showed increased inflammation in relation to the extent of the cysticercus in the brain parenchyma. The location of cysticerci within the brain is a factor that determines the extent and degree of the immune response following anticysticidal treatment. Similar changes may occur in treated human infections. Our work could contribute to explain the differences in response to antiparasitic treatment in different forms of human neurocysticercosis.

Efficacy and safety of praziquantel, tribendimidine and mebendazole in patients with co-infection of Clonorchis sinensis and other helminths

BACKGROUND

Both tribendimidine and mebendazole are broad-spectrum drugs for anti-intestinal nematodes. We aim to assess the efficacy and safety of tribendimidine and mebendazole in patients with co-infection of Clonorchis sinensis and other helminths.

METHOD

We performed a randomized open-label trial in Qiyang, People's Republic of China. Eligible participants were randomly assigned to one of four groups: (i) a single dose of 400 mg tribendimidine, (ii) 200 mg tribendimidine twice daily, (iii) 75 mg/kg praziquantel divided in four doses within 2 days, and (iv) a single dose of 400 mg mebendazole. Cure rates and egg reduction rates were assessed, and adverse events were monitored after treatments. Uncured patients accepted the second treatment with the same drugs after the first treatment.

RESULTS

156 patients were eligible for the study. Results from the first treatment showed that the cure rates of single-dose tribendimidine and praziquantel against C. sinensis were 50% and 56.8%, respectively; the single-dose tribendimidine achieved the cure rate of 77.8% in the treatment for hookworm, which was significantly higher than that of praziquantel; Low cure rates were obtained in the treatment of single-dose tribendimidine against Ascaris lumbricoides and Trichuris trichiura (28.6% and 23.1%). Results of the second treatment illustrated the cure rates of tribendimidine and praziquantel against C. sinensis were 78.1% and 75%, respectively. Most adverse events were mild and transient. Adverse events caused by tribendimidine were significantly less than praziquantel.

CONCLUSION

Single-dose tribendimidine showed similar efficacy against C. sinensis as praziquantel with less adverse events, and achieved significantly higher cure rate in the treatment for hookworm than those of praziquantel and mebendazole. Low cure rates, which were still higher than other drugs, were obtained in the treatment of single-dose tribendimidine against Ascaris lumbricoides and Trichuris trichiura.

TRIAL REGISTRATION

Controlled-Trials.com ISRCTN55086560.

Praziquantel, mefloquine-praziquantel, and mefloquine-artesunate-praziquantel against Schistosoma haematobium: a randomized, exploratory, open-label trial

Background

Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel. Hence, there is a pressing need to develop additional therapeutics against schistosomiasis. The antimalarial drug mefloquine shows antischistosomal activity in animal models and clinical trials, which calls for further investigations.

Methodology

We comparatively assessed the efficacy and tolerability of the following treatments against Schistosoma haematobium in school-aged children in Côte d'Ivoire: (i) praziquantel (40 mg/kg; standard treatment); (ii) mefloquine (25 mg/kg) combined with praziquantel (40 mg/kg); and (iii) mefloquine-artesunate (3× (100 mg artesunate +250 mg mefloquine)) combined with praziquantel (40 mg/kg) (treatments administered on subsequent days). Two urine samples were collected before, and on days 21–22 and 78–79 after the first dosing.

Principal Findings

Sixty-one children were present on all examination time points and had complete datasets. No difference in efficacy was observed between the three treatment groups on either follow-up. On the 21–22 day posttreatment follow-up, based on available case analysis, cure rates of 33% (95% confidence interval (CI) 11–55%), 29% (95% CI 8–50%), and 26% (95% CI 5–48%) were observed for praziquantel, mefloquine-artesunate-praziquantel, and mefloquine-praziquantel, respectively. The corresponding egg reduction rates were 94% and above. On the second follow-up, observed cure rates ranged from 19% (praziquantel) to 33% (mefloquine-artesunate-praziquantel), and egg reduction rates were above 90%. Praziquantel monotherapy was the best tolerated treatment. In the mefloquine-artesunate-praziquantel group, adverse events were reported by 91% of the participants, and in the mefloquine-praziquantel group, 95% experienced adverse events. With the exception of abdominal pain at moderate severity, adverse events were mild.

Conclusions/Significance

The addition of mefloquine or mefloquine-artesunate does not increase the efficacy of praziquantel against chronic S. haematobium infection. Additional studies are necessary to elucidate the effect of the combinations against acute schistosomiasis.

The antimalarial drug mefloquine shows activity against blood flukes that cause the disease schistosomiasis. In animal studies it has been found that a mefloquine-praziquantel combination kills blood flukes more effectively than praziquantel alone. Combining praziquantel with another drug might therefore increase efficacy, broaden the spectrum of activity, and delay the development of drug resistance. We designed a study in Ivorian school children to assess the efficacy and tolerability of mefloquine and mefloquine-artesunate combined with praziquantel against the blood fluke Schistosoma haematobium. The administration of the antimalarials and praziquantel was spaced by a day. Treatment outcomes were assessed twice, on days 21–22 and 78–79 after the first dosing to determine the effect against adult and juvenile S. haematobium, respectively. At both follow-ups, high reduction in the intensity of infection (egg reduction rates of 94–96%), but low cure rates (26–33%) were observed in the three treatment groups. Adverse events were common, particularly in children treated with mefloquine-praziquantel and mefloquine-artesunate-praziquantel. Our study suggests that the addition of mefloquine and mefloquine-artesunate to praziquantel has no benefit in the treatment of chronic S. haematobium infection. However, further investigations are warranted to evaluate the effect of combination therapy on juvenile flukes and longer-term morbidity profiles.

A school-based cross-sectional survey of adverse events following co-administration of albendazole and praziquantel for preventive chemotherapy against urogenital schistosomiasis and soil-transmitted helminthiasis in Kwale County, Kenya

BACKGROUND

Soil-transmitted helminths and schistosomiasis are mostly prevalent in developing countries due to poor sanitation and lack of adequate clean water. School-age children tend to be the target of chemotherapy-based control programmes because they carry the heaviest worm and egg burdens. The present study examines adverse events (AEs) experienced following co-administration of albendazole and praziquantel to school-age children in a rural area in Kwale County, Kenya.

METHODS

Children were treated with single doses of albendazole and praziquantel tablets and then interviewed using a questionnaire for post treatment AEs.

RESULTS

Overall, 752 children, 47.6% boys, participated in the study. Their median (interquartile range) age was 12.0 (10.0-14.0) years. A total of 190 (25.3%) children reportedly experienced at least one AE. In total, 239 cases of AEs were reported with the most frequent being abdominal pains (46.3%), dizziness (33.2%) and nausea (21.1%). Majority of the reported AEs (80.8%) resolved themselves while 12.1% and 6.3% were countered by, respectively, self-medication and visiting a nearby health facility. More girls (60.5%) than boys (39.5%) reported AEs (P = 0.027).

CONCLUSIONS

The AEs were mild and transient, and were no worse than those expected following monotherapy. The current study adds to the evidence base that dual administration of albendazole and praziquantel in school-based mass drug administration is safe with only mild adverse events noted.

Therapy for neurocysticercosis

Therapy for neurocysticercosis has advanced during the last 20 years with the advent of albendazole (Zentel) and praziquantel (Cysticide). Albendazole is the current medication of choice for the treatment of neurocysticercosis and is recommended for symptomatic patients with multiple viable cysts in the brain parenchyma. Albendazole may also be useful in extraparenchymal cysticercosis, especially in the subarachnoid racemose form, when complete surgical resection of the cysts is usually impracticable. Currently, there is an intense debate over the value and safety of anticysticercal therapy. Causes for failure of anticysticercal therapy include high inter-individual variability in plasma concentration of albendazole sulfoxide and the complex interactions of several drugs with the albendazole metabolite. Furthermore, albendazole sulfoxide is an enantiomeric mixture of (+)- and (-)-albendazole sulfoxide with accumulation of the (+)-enantiomer in the cerebrospinal fluid. However, the question over which enantiomer is effective against cysticerci remains to be clarified.

Efficacy and safety of two closely spaced doses of praziquantel against Schistosoma haematobium and S. mansoni and re-infection patterns in school-aged children in Niger

The aim of this study was to assess the efficacy and safety of two closely spaced doses of praziquantel (PZQ) against Schistosoma haematobium and S. mansoni infection in school-aged children, and to characterise re-infection patterns over a 12-month period. The study was carried out in five villages in western Niger: Falmado, Seberi and Libore (single S. haematobium infection foci), and Diambala and Namarigoungou (mixed S. haematobium-S. mansoni infection foci). Parasitological examinations consisted of triplicate urine filtrations and triplicate Kato-Katz thick smears at each visit. Two 40mg/kg oral doses of PZQ were administered 3 weeks apart. Adverse events were monitored within 4h after dosing by the survey team and 24h after treatment using a questionnaire. Our final study cohort comprised 877 children who were infected with either S. haematobium, or S. mansoni, or both species concurrently and received both doses of PZQ. Follow-up visits were conducted 6 weeks, 6 months and 12 months after the first dose of PZQ. At baseline, the geometric mean (GM) infection intensity of S. haematobium ranged from 3.6 (Diambala) to 30.3eggs/10ml of urine (Falmado). The GM infection intensity of S. mansoni ranged from 86.7 (Diambala) to 151.4eggs/g of stool (Namarigoungou). Adverse events were reported by 33.0% and 1.5% of the children after the first and second doses of PZQ, respectively. We found cure rates (CRs) in S. haematobium-infected children 3 weeks after the second dose of PZQ ranging between 49.2% (Falmado) and 98.4% (Namarigoungou) and moderate-to-high egg reduction rates (ERRs) (71.4-100%). Regarding S. mansoni, only moderate CRs and ERRs were found (51.7-58.8% in Diambala, 55.2-60.2% in Namarigoungou). Twelve months post-treatment, prevalence rates approached pre-treatment levels, but infection intensities remained low. In conclusion, PZQ, given in two closely spaced doses, is efficacious against S. haematobium, but the low ERR observed against S. mansoni raises concern about mounting PZQ tolerance.

Safety and efficacy of praziquantel syrup (Epiquantel®) against Schistosoma haematobium and Schistosoma mansoni in preschool-aged children in Niger

Given the characteristic age-prevalence curve of Schistosoma infection, preventive chemotherapy with praziquantel is primarily targeted at school-aged children, whilst, in highly endemic areas, other high-risk groups might be included for regular treatment. Nevertheless, schistosomiasis can affect children well before they reach school-age, but this population group is usually excluded from preventive chemotherapy. We assessed the safety and efficacy of praziquantel syrup (Epiquantel®) in preschool-aged children in three villages of Niger. Children aged ≤72 months provided multiple urine and stool samples that were microscopically examined using standard protocols. Schistosoma-positive children were treated with praziquantel syrup at a dose of 40 mg/kg after a meal of millet porridge. Children remained under medical supervision for 4h and adverse events were recorded. Additionally, a questionnaire was administrated to the mothers/guardians 24h post-treatment for further probing of adverse events. Treatment efficacy was evaluated 3 and 6 weeks post-treatment using multiple stool and urine samples. A third of the 243 treated children reported adverse events within 4h, whilst a further 6.2% reported adverse events upon probing 24h post-treatment. Abdominal pain, bloody diarrhoea and sleepiness were the most common adverse events, but these were transient and self-limiting. Praziquantel syrup showed moderate-to-high efficacy against Schistosoma haematobium with egg reduction rates of 69.4% and 71.2% 3 and 6 weeks post-treatment and cure rates of 85.7% (95% confidence interval (CI) 79.7-90.5%) and 94.9% (95% CI 90.5-97.6%), respectively. Considerably lower cure and egg reduction rates were observed against Schistosoma mansoni (e.g. cure rate at 6-week post-treatment follow-up was only 50.6% (95% CI 39.9-61.2%). Concluding, praziquantel syrup is well tolerated in preschool-aged children with moderate-to-high efficacy against S. haematobium, but considerably lower efficacy against S. mansoni in Niger. A larger study is warranted to investigate the observed differences in species-specific susceptibilities and to assess operational issues and community-effectiveness.

Efficacy and safety of praziquantel in preschool-aged children in an area co-endemic for Schistosoma mansoni and S. haematobium

BACKGROUND

In sub-Saharan Africa the recommended strategy to control schistosomiasis is preventive chemotherapy. Emphasis is placed on school-aged children, but in high endemicity areas, preschool-aged children are also at risk, and hence might need treatment with praziquantel. Since a pediatric formulation (e.g., syrup) is not available outside of Egypt, crushed praziquantel tablets are used, but the efficacy and safety of this treatment regimen is insufficiently studied.

METHODOLOGY

We assessed the efficacy and safety of crushed praziquantel tablets among preschool-aged children (<6 years) in the Azaguié district, south Côte d'Ivoire, where Schistosoma mansoni and S. haematobium coexist. Using a cross-sectional design, children provided two stool and two urine samples before and 3 weeks after treatment. Crushed praziquantel tablets, mixed with water, were administered at a dose of 40 mg/kg. Adverse events were assessed and graded 4 and 24 hours posttreatment by interviewing mothers/guardians.

PRINCIPAL FINDINGS

Overall, 160 preschool-aged children had at least one stool and one urine sample examined with duplicate Kato-Katz thick smears and a point-of-care circulating cathodic antigen (POC-CCA) cassette for S. mansoni, and urine filtration for S. haematobium diagnosis before and 3 weeks after praziquantel administration. According to the Kato-Katz and urine filtration results, we found high efficacy against S. mansoni (cure rate (CR), 88.6%; egg reduction rate (ERR), 96.7%) and S. haematobium (CR, 88.9%; ERR, 98.0%). POC-CCA revealed considerably lower efficacy against S. mansoni (CR, 53.8%). Treatment was generally well tolerated, but moderately severe adverse events (i.e., body and face inflammation), were observed in four Schistosoma egg-negative children.

CONCLUSIONS/SIGNIFICANCE

Crushed praziquantel administered to preschool-aged children at a dose of 40 mg/kg is efficacious against S. mansoni and S. haematobium in a co-endemic setting of Côte d'Ivoire. Further research is required with highly sensitive diagnostic tools and safety must be investigated in more depth.

TRIAL REGISTRATION

Controlled-Trials.com ISRCTN53172722.

Performance and safety of praziquantel for treatment of intestinal schistosomiasis in infants and preschool children

Background

In 2012 the WHO formally recognised that infants and preschool children are at significant risk of schistosomiasis and qualify for treatment with praziquantel (PZQ). Targeted surveys determining both the performance and safety of this drug are now needed in endemic areas. We have formally assessed parasitological cure and putative side-effects in a prospective cohort of Schistosoma mansoni-infected children (aged 5 months–7 years old) in lakeshore settings of Uganda.

Methodology/Principal Findings

From a total of 369 children found to be egg-patent for intestinal schistosomiasis, 305 were followed-up three to four weeks after PZQ treatment and infection status re-assessed. Separately, a previously tested side-effect questionnaire was employed before and 24 hours after PZQ treatment to assess incidence and amelioration of symptoms in young children and their mothers. While the overall observed parasitological cure was 56.4%, a significant difference was found between a sub-set of children who had a history of multiple PZQ treatments (between one and four in an 18 month period), where cure rate was 41.7%, and those who had never received treatment (cure rate was 77·6%). PZQ proved to be safe, with only mild reported side effects which cleared within a month after treatment. Prevalence of reported symptoms was significantly lower in children than in mothers, and fewer side-effects were reported upon subsequent rounds of PZQ treatment.

Conclusion/Significance

Our findings show that PZQ treatment of young children resulted in satisfactory cure rates, and marked reduction in egg-output, with only mild and transient reported side-effects. However, the cure rate is clearly lower in younger children and those with history of previous treatment. Cure rate, but not egg reduction rate, was also lower in children with heavier pre-intervention infection intensity. With chemotherapy now recommended as a long-term strategy for disease control in young children, research into optimising the periodicity of targeted treatment strategies is now crucial.

Although there is now extensive evidence for infection in preschool-aged children, and even a change in WHO guidelines endorsing treatment of this young age class in endemic areas, very little work has been published on the performance of praziquantel in children below the age of six. Previous work on praziquantel performance in preschool aged children focused on Schistosoma haematobium infections (urogenital schistosomiasis), with few observational studies published for S. mansoni infections (intestinal schistosomiasis). With a formalised protocol, we show that delivery of praziquantel to preschool-aged children living in endemic areas is safe and efficacious. However, this work has also shed light on dynamics never previously explored. History of previous treatment and age below three years proved to be determining factors for the outcome of treatment. This work provides firm evidence that in an endemic population certain young individuals were simply not cured (no egg or antigen cessation) after standard doses of praziquantel. This potential for non-cure should not go overlooked since exposure to drug without cure (either due to parasite or human factors) can lead to emergence and spread of resistance to praziquantel. Bearing in mind that praziquantel is the only commercially available drug against schistosomiasis, we recommend further research to understand these dynamics.

[Opisthorchiasis: tradition and innovation]

THE PURPOSE OF THE REVIEW: Present new data on the causative agent, pathogenesis, diagnosis and treatment of opisthorchiasis.

RECENT LITERATURE DATA

When samples of parasites were genotyped by novel nuclear marker Pm-int9, it was shown various properties of Opisthorchis viverrini, O. felineus and C. sinensis. It has been proven the oxidant damage to DNA of biliary epithelium cells infected with opisthorchiasis, and overexpressed of cellular protooncogene c-Ski, as well as platelet-derived growth factor alpha (Pdgfa) gene, which in some cases leads to the development of cholangiocarcinoma. Describes the innovations in the diagnosis of opisthorchiasis: primers OP1 and OP2 are used to amplify the ITS2 region rDNK eggs and metacercariae of Opisthorchis in feces. Opisthorchiasis treatment remains traditional - praziquantel, at least - with albendazole. Treatment of opisthorchiasis patients with praziquantel was shown to reduce inflammation-mediated tissue damage and carcinogenesis.

[Compliance of film-coated praziquantel tablets in schistosomiasis transmission-controlled areas]

OBJECTIVE

To observe the compliance of film-coated praziquantel tablets in the schistosomiasis transmission controlled areas, so as to provide the evidence for the establishment of chemotherapy intervention measures in these areas.

METHODS

In the areas of schistosomiasis transmission controlled in Sichuan Province, 234 people were selected as film-coated praziquantel group (FCPG), and 203 people were selected as praziquantel group (PG). A questionnaire survey was implemented and the compliance of chemotherapy of the 2 groups was compared.

RESULTS

In PG, all the people indicated that the praziquantel tablets has bad smell, 98.0% of the people had side-effects, such as nausea, headache, 69.5% thought the medicine was harmful to health subjectively, and 99.5% thought that it was too much dose of tablets for taking one time. In FCPG, all the people indicated that the film-coated praziquantel tablets had no bad smell, 18.8% of the people had side-effects, and 74.4% would like to choose film-coated praziquantel tablets. The rates of knowledge of praziquantel of PG and FCPG were 50.7% and 29.1%, respectively ( chi2 = 21.449, P = 0.01).

CONCLUSIONS

The film-coated praziquantel tablets have no bad smell and lighter side-effects. The compliance of the film-coated praziquantel tablets is high in the areas of schistosomiasis transmission controlled, so the film-coated praziquantel tablets are worth to popularize and apply.

Treatment with anthelminthics during pregnancy: what gains and what risks for the mother and child?

In 1994 and 2002, respectively, the World Health Organisation proposed that treatment for hookworm and schistosomiasis could be provided during pregnancy. It was hoped that this might have benefits for maternal anaemia, fetal growth and perinatal mortality; a beneficial effect on the infant response to immunisation was also hypothesised. Three trials have now been conducted. Two have examined the effects of benzimidazoles; one (the Entebbe Mother and Baby Study) the effects of albendazole and praziquantel. All three were conducted in settings of high prevalence but low intensity helminth infection. Results suggest that, in such settings and given adequate provision of haematinics, the benefit of routine anthelminthics during pregnancy for maternal anaemia may be small; none of the other expected benefits has yet been demonstrated. The Entebbe Mother and Baby Study found a significant adverse effect of albendazole on the incidence of infantile eczema in the whole study population, and of praziquantel on the incidence of eczema among infants of mothers with Schistosoma mansoni. Further studies are required in settings that differ in helminth species and infection intensities. Further research is required to determine whether increased rates of infantile eczema translate to long-term susceptibility to allergy, and to explore the underlying mechanisms of these effects. The risks and benefits of routine anthelminthic treatment in antenatal clinics may need to be reconsidered.

Resolution of praziquantel

Background

Praziquantel remains the drug of choice for the worldwide treatment and control of schistosomiasis. The drug is synthesized and administered as a racemate. Use of the pure active enantiomer would be desirable since the inactive enantiomer is associated with side effects and is responsible for the extremely bitter taste of the pill.

Methodology/Principal Findings

We have identified two resolution approaches toward the production of praziquantel as a single enantiomer. One approach starts with commercially available praziquantel and involves a hydrolysis to an intermediate amine, which is resolved with a derivative of tartaric acid. This method was discovered through an open collaboration on the internet. The second method, identified by a contract research organisation, employs a different intermediate that may be resolved with tartaric acid itself.

Conclusions/Significance

Both resolution procedures identified show promise for the large-scale, economically viable production of praziquantel as a single enantiomer for a low price. Additionally, they may be employed by laboratories for the production of smaller amounts of enantiopure drug for research purposes that should be useful in, for example, elucidation of the drug's mechanism of action.

The drug praziquantel (PZQ) is used very widely in both animal and human medicine, where it is the mainstay of the treatment of the neglected tropical disease schistosomiasis. The drug is currently manufactured and administered as a racemate (1∶1 mixture of enantiomers) but for various reasons the large-scale production of PZQ as the single active enantiomer is very desirable. We describe here the preparation of praziquantel as a single enantiomer using classical resolution. The protocols are experimentally simple and inexpensive. One method was found and validated by an unusual research mechanism—open science—where the details of the collaboration (involving academic and industrial partners) and all research data were available on the web as they were acquired, and anyone could participate. The other route was found in parallel by a contract research organisation. Besides being possible routes by which praziquantel may be produced in large quantities for the affected communities, it is also hoped that these methods can be used for the production of smaller quantities of enantiopure PZQ for pharmacological studies.

[Temperature recrudescence caused by praziquantel treatment after falling to normal automatically in acute schistosomiasis patients: a report of 19 cases]

Nineteen cases of acute schistosomiasis patients whose temperatures had fallen to normal automatically were treated with praziquantel, and their temperatures recrudesced after the treatment. Then they were treated with larger dose of praziquantel according to the scheme of acute schistosomiasis therapy, and all of them were cured.

A multicentre randomized controlled trial of the efficacy and safety of single-dose praziquantel at 40 mg/kg vs. 60 mg/kg for treating intestinal schistosomiasis in the Philippines, Mauritania, Tanzania and Brazil

BACKGROUND

Praziquantel at 40 mg/kg in a single dose is the WHO recommended treatment for all forms of schistosomiasis, but 60 mg/kg is also deployed nationally.

METHODOLOGY/PRINCIPAL FINDINGS

Four trial sites in the Philippines, Mauritania, Tanzania and Brazil enrolled 856 patients using a common protocol, who were randomised to receive praziquantel 40 mg/kg (n  =  428) or 60 mg/kg (n  =  428). While the sites differed for transmission and infection intensities (highest in Tanzania and lowest in Mauritania), no bias or heterogeneity across sites was detected for the main efficacy outcomes. The primary efficacy analysis was the comparison of cure rates on Day 21 in the intent-to-treat population for the pooled data using a logistic model to calculate Odd Ratios allowing for baseline characteristics and study site. Both doses were highly effective: the Day 21 cure rates were 91.7% (86.6%-98% at individual sites) with 40 mg/kg and 92.8% (88%-97%) with 60 mg/kg. Secondary parameters were eggs reduction rates (ERR), change in intensity of infection and reinfection rates at 6 and 12 months. On Day 21 the pooled estimate of the ERR was 91% in both arms. The Hazard Ratio for reinfections was only significant in Brazil, and in favour of 60 mg/kg on the pooled estimate (40 mg/kg: 34.3%, 60 mg/kg: 23.9%, HR  =  0.78, 95% CI  = [0.63;0.96]). Analysis of safety could not distinguish between disease- and drug-related events. 666 patients (78%) reported 1327 adverse events (AE) 4 h post-dosing. The risk of having at least one AE was higher in the 60 than in the 40 mg/kg group (83% vs. 73%, p<0.001). At 24 h post-dosing, 456 patients (54%) had 918 AEs with no difference between arms. The most frequent AE was abdominal pain at both 4 h and 24 h (40% and 24%).

CONCLUSION

A higher dose of 60 mg/kg of praziquantel offers no significant efficacy advantage over standard 40 mg/kg for treating intestinal schistosomiasis caused by either S. mansoni or S. japonicum. The results of this study support WHO recommendation and should be used to inform policy decisions in the countries.

Schistosoma haematobium treatment in 1-5 year old children: safety and efficacy of the antihelminthic drug praziquantel

Background

Morbidity due to schistosomiasis is currently controlled by treatment of schistosome infected people with the antihelminthic drug praziquantel (PZQ). Children aged up to 5 years are currently excluded from schistosome control programmes largely due to the lack of PZQ safety data in this age group. This study investigated the safety and efficacy of PZQ treatment in such children.

Methods

Zimbabwean children aged 1–5 years (n = 104) were treated with PZQ tablets and side effects were assessed by questionnaire administered to their caregivers within 24 hours of taking PZQ. Treatment efficacy was determined 6 weeks after PZQ administration through schistosome egg counts in urine. The change in infection levels in the children 1–5 years old (n = 100) was compared to that in 6–10 year old children (n = 435).

Principal Findings

Pre-treatment S. haematobium infection intensity in 1–5 year olds was 14.6 eggs/10 ml urine and prevalence was 21%. Of the 104 children, 3.8% reported side effects within 24 hours of taking PZQ treatment. These were stomach ache, loss of appetite, lethargy and inflammation of the face and body. PZQ treatment significantly reduced schistosome infection levels in 1–5 year olds with an egg reduction rate (ERR) of 99% and cure rate (CR) of 92%. This was comparable to the efficacy of praziquantel in 6–10 year olds where ERR was 96% and CR was 67%.

Interpretation/Significance

PZQ treatment is as safe and efficacious in children aged 1–5 years as it is in older children aged 6–10 years in whom PZQ is the drug of choice for control of schistosome infections.

Urogenital schistosomiasis is an important, but neglected, infectious disease affecting over 100 million people, mainly in Africa. Children carry the heaviest burden of infection with children as young as 1 year old showing signs of infection. Children aged 5 years and below are currently excluded from schistosome control programmes for several reasons, including operational difficulties associated with accessing preschool children, misconceptions about their level of exposure to infective water and lack of safety data on the drug of choice for schistosome control, praziquantel, in children aged 5 years and below. This study was one of a small number of studies recently funded by the World Health Organization to investigate the need for praziquantel treatment in preschool children (aged 1–5 years) and to subsequently assess the safety and efficacy of the drug praziquantel in this age group. This study confirmed that preschool children carry significant levels of schistosome infection, exceeding those carried by their parents/guardians, highlighting the urgent need for their immediate inclusion in schistosome control programmes. The study also showed that praziquantel treatment is as safe and efficacious in children aged 1–5 years as it is in older children aged 6–10 years who are currently the target for mass drug administration.

[One case of acute kidney injury caused by praziquantel]

This paper reported one case of acute kidney injury caused by praziquantel.

Effect of single-dose anthelmintic treatment during pregnancy on an infant's response to immunisation and on susceptibility to infectious diseases in infancy: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Helminth infections affect the human immune response. We investigated whether prenatal exposure to and treatment of maternal helminth infections affects development of an infant's immune response to immunisations and unrelated infections.

METHODS

In this randomised, double-blind, placebo-controlled trial, we enrolled 2507 women in the second or third trimester of pregnancy who were planning to deliver in Entebbe General Hospital, Entebbe, Uganda. With a computer-generated random number sequence in blocks of 100, we assigned patients to 440 mg albendazole and 40 mg/kg praziquantel (n=628), 440 mg albendazole and a praziquantel-matching placebo (n=625), 40 mg/kg praziquantel and an albendazole-matching placebo (n=626), or an albendazole-matching placebo and praziquantel-matching placebo (n=628). All participants and hospital staff were masked to allocation. Primary outcomes were immune response at age 1 year to BCG, tetanus, and measles immunisation; incidence of infectious diseases during infancy; and vertical HIV transmission. Analysis was by intention-to-treat. This trial is registered, number ISRCTN32849447.

FINDINGS

Data were available at delivery for 2356 women, with 2345 livebirths; 2115 (90%) of liveborn infants remained in follow-up at 1 year of age. Neither albendazole nor praziquantel treatments affected infant response to BCG, tetanus, or measles immunisation. However, in infants of mothers with hookworm infection, albendazole treatment reduced interleukin-5 (geometric mean ratio 0·50, 95% CI 0·30-0·81, interaction p=0·02) and interleukin-13 (0·52, 0·34-0·82, 0·0005) response to tetanus toxoid. The rate per 100 person-years of malaria was 40·9 (95% CI 38·3-43·7), of diarrhoea was 134·1 (129·2-139·2), and of pneumonia was 22·3 (20·4-24·4). We noted no effect on infectious disease incidence for albendazole treatment (malaria [hazard ratio 0·95, 95% CI 0·79-1.14], diarrhoea [1·06, 0·96-1·16], pneumonia [1·11, 0·90-1·38]) or praziquantel treatment (malaria [1·00, 0·84-1·20], diarrhoea [1·07, 0·98-1·18], pneumonia [1·00, 0·80-1·24]). In HIV-exposed infants, 39 (18%) were infected at 6 weeks; vertical transmission was not associated with albendazole (odds ratio 0·70, 95% CI 0·35-1·42) or praziquantel (0·60, 0·29-1·23) treatment.

INTERPRETATION

These results do not accord with the recently advocated policy of routine antenatal anthelmintic treatment, and the value of such a policy may need to be reviewed.

FUNDING

Wellcome Trust.

[Efficacy and adverse effects of film coated praziquantel for treatment of schistosomiasis japonica]

OBJECTIVE

To understand the adverse and curative effects of film coated praziquantel for treatment of schistosomiasis japonica.

METHODS

A questionnaire survey was conducted among 6 to 65 years old inhabitants from epidemic areas of schistosomiasis japonica in Jiangxi, Anhui and Hubei provinces, while indirect haemagglutination assay (IHA) was also administrated. The Serological positives were tested by Kato-Katz technique. A total of 509 habitats of serological positives and healthy persons were given praziquantel. 460 targets with no relative symptoms were followed up for adverse effect of drugs in one month and efficacy evaluation of praziquantel was carried out in 104 parasitological positives 3 months post-treatment.

RESULTS

The 84.7% (144/170) individuals thought film coated tablets were no smell or only with little smell while 92.9%(315/339) targets in control group fell that tablets smelled bad. The total side effect rates of film coated praziquantel group and control group in 1-2 hours post-treatment were 20.30% (27/133) and 83.18% (272/327) respectively. There was significantly different between two groups (chi(2) = 164.316, P < 0.05). The adverse effect rates of film coated praziquantel group in neuromuscular system, digestive system and cardiovascular system were 15.79% (21/133), 9.77% (13/133), 2.26% (3/133) individually which were significantly lower than those of control groups with 81.65% (267/327), 49.24% (161/327), 12.84% (42/327) in corresponding systems (chi(2)(neuromuscular system) = 175.188, chi(2)(digestive system) = 62.601, chi(2)(cardiovascular system) = 12.010, P < 0.05). And the adverse effect rate of allergic reaction of film coated group was no significant difference with control group (2.26%(3/133) versus 0.92% (3/327), chi(2) = 1.315, P = 0.235). One day after treatment, the adverse effect rate of film coated tablets of praziquantel decreased to 3.01% (4/133), significantly lower than that of control group (P < 0.05). There was no significant difference after 2 weeks treatment while the adverse effect rates decreased to 0.75%(1/133), 0.61% (2/327) in film coated praziquantel group and control group respectively (chi(2) = 0.029, P = 0.642). The curative rates 3 months post treatment were 84.91% (45/51) in film coated tablets of praziquantel group and 82.35% (42/53) in control group without significant difference (chi(2) = 1.536, P = 0.215).

CONCLUSION

The smell and adverse effects of film coated tablets of praziquantel were decreased significantly and its efficacy for treatment of schistosomiasis japonica was equal to the control tablets. The film coated tablets of praziquantel might be applied in field widely after a further verification.

Taste, a new incentive to switch to (R)-praziquantel in schistosomiasis treatment

BACKGROUND

Praziquantel (PZQ) is the drug compound of choice in the control and treatment of schistosomiasis. PZQ is administered as a racemate, i. e. 1ratio1 mixture of enantiomers. The schistosomicidal activity arises from one PZQ-enantiomer, whereas the other enantiomer does not contribute to the activity. The WHO's Special Programme for Research and Training in Tropical Diseases (TDR) has assigned the low-cost preparation of pure schistosomicidal (-)-PZQ a key priority for future R&D on PZQ, but so far this transition has not happened. PZQ has two major administration drawbacks, the first being the high dose needed, and its well documented bitter and disgusting taste. Attempts of taste-masking by low-cost means have not been successful. We hypothesized that the non-schistosomicidal component in PZQ would be the main contributor to the unpleasant taste of the drug. If the hypothesis was confirmed, the two major administration drawbacks of PZQ, the high dose needed and its bitter taste, could be addressed in one go by removing the component contributing to the bitter taste.

METHODS AND FINDINGS

PZQ was separated into its schistosomicidal and the non-schistosomicidal component, the absolute stereochemical configuration of (-)-PZQ was determined to be (R)-PZQ by X-ray crystallography, and the extent of bitterness was determined for regular racemic PZQ and the schistosomicidal component in a taste study in humans.

FINDING

The schistosomicidal component alone is significantly less bitter than regular, racemic PZQ.

CONCLUSION

Our hypothesis is confirmed. We propose to use only the pure schistosomicidal component of PZQ, offering the advantage of halving the dose and expectedly improving the compliance due to the removal of the bitter taste. Therefore, (R)-PZQ should be specifically suitable for the treatment of school-age children against schistosomiasis. With this finding, we would like to offer an additional incentive to the TDR's recommendation to switch to the pure schistosomicidal (R)-PZQ.

[Effect of praziquantel and ursodeoxycholic acid therapy on bile lithogenicity in patients with opisthorchosis on the background of main variant of standard diet]

A total of 56 patients were examined. It is revealed that there is a significant increase of concentration of indirect bilirubin, cholesterol, albumins in cystic bile after monotherapy with praziquantel as compared to healthy persons. It is evidence of high bile lithogenicity, defined lower result of lithogenesis resolution after ongoing therapy (29%). Inclusion of ursodeoxycholic acid into anthelmintic therapy makes it possible to reach more significant litholitical effect of ongoing therapy (70,5%).

Efficacy and side effects of praziquantel treatment against Schistosoma haematobium infection among primary school children in Zimbabwe

We examined the efficacy of praziquantel against Schistosoma haematobium among primary school children during a school-based deworming programme in the Burma Valley commercial farming area and the Nyamaropa rural areas in Zimbabwe, where the disease is highly endemic. Among 767 individuals infected with S. haematobium, 675 (88.0%) received treatment. Two single oral doses of 40mg/kg praziquantel were given 6 weeks apart. Of the 675 participants, heavy infection intensity was more common in males than females (chi(2)=6.61, P=0.010). Six weeks later, 624 participants (92.4%) were successfully followed up. The overall cure rate was 88.5% and the egg reduction rate was 98.2%. The highest cure rate was among those individuals with light infection. Seventy-two individuals remained infected at 6 weeks post treatment, among which 3 and 69 individuals had heavy and light infection, respectively. Forty-six of these children resolved following a second round of treatment at 6 weeks follow-up. Of the remaining children successfully followed-up, 22 resolved after a third round of treatment 6 months later. A wide range of observed mild and transient side effects were not associated with egg intensity. The parasitological cure rate was not associated with gender or age. Our study demonstrates that praziquantel is efficacious against S. haematobium in Zimbabwe, although low levels of persistent infection warrant further investigation.

Could neurocysticercosis be the cause of "onchocerciasis-associated" epileptic seizures?

We conducted a nodule prevalence survey in four onchocerciasis sentinel communities in Moyo and two in Kanungu districts of Uganda. Seven (33.3%) out of 21 excised "onchocercomas" (nodules) in Moyo District and excised onchocercomas from four of six persons in Kanungu District turned out to be cysts of Taenia solium. We concluded that the prediction of nodule prevalence for noninvasive rapid epidemiologic assessment (REA) to target areas for mass chemotherapy with ivermectin in the African Program for Onchocerciasis Control (APOC) supported areas may have been influenced by other pathologies. T. solium infection may be the main cause of "onchocerciasis-associated epileptic seizures" in many onchocerciasis endemic communities that have been causally linked to onchocerciasis. Lastly, widespread neurocysticercosis may be a concern in mass treatment programs that provide praziquantel (for managing schistosomiasis) or albendazole (for managing intestinal worms or lymphatic filariasis) because these drugs may kill cerebral cysticerci, resulting in severe adverse events.

Schistosomiasis and pregnancy

Currently, schistosomes infect approximately 40 million women of child-bearing age, yet little is known about schistosome-associated morbidity in pregnant women and their offspring. Animal models indicate a deleterious effect of schistosome infection on maternal, fetal and neonatal outcomes. Case reports have documented maternal infection in association with poor birth outcomes, and two observational studies indicate that maternal schistosome infection might be associated with decreased birth weight. Rigorously identifying and quantifying the impact of schistosome infection on pregnancy outcomes with well-designed observational and treatment studies are crucial for improving birth outcomes in schistosome-endemic areas. In addition, studies that address the safety of praziquantel during pregnancy could lead to further adoption of the recent informal recommendation by the World Health Organization to treat schistosome-infected pregnant and lactating women.