Here is the design of a clinical trial:

Official Title: Phase II PK/PD Driven Dose Finding Trial of Praziquantel in Children Under Four

Included conditions:
- Schistosomiasis
- Schistosomiasis Mansoni
- Schistosoma Japonicum Infection

Study Armgroups:
- {'label': 'Praziquantel 40 mg/kg dose only baseline treatment', 'type': 'ACTIVE_COMPARATOR', 'description': '150 children will receive 40 mg/kg Praziquantel at baseline as single treatment and placebo six months following baseline', 'interventionNames': ['Drug: Praziquantel']}
- {'label': 'Praziquantel 80 mg/kg dose only baseline treatment', 'type': 'ACTIVE_COMPARATOR', 'description': '150 children will receive 80 mg/kg Praziquantel at baseline as single treatment and placebo six months following baseline', 'interventionNames': ['Drug: Praziquantel']}
- {'label': 'Praziquantel 40 mg/kg dose at baseline and 6 months', 'type': 'ACTIVE_COMPARATOR', 'description': '150 children will receive 40 mg/kg Praziquantel at baseline and again six months later.', 'interventionNames': ['Drug: Praziquantel']}
- {'label': 'Praziquantel 80 mg/kg dose at baseline and 6 months', 'type': 'ACTIVE_COMPARATOR', 'description': '150 children will receive 80 mg/kg Praziquantel at baseline and again six months later.', 'interventionNames': ['Drug: Praziquantel']}

Interventions:
- {'type': 'DRUG', 'name': 'Praziquantel', 'description': 'Praziquantel given as crushed tablets (40 or 80 mg/kg)', 'armGroupLabels': ['Praziquantel 40 mg/kg dose at baseline and 6 months', 'Praziquantel 40 mg/kg dose only baseline treatment', 'Praziquantel 80 mg/kg dose at baseline and 6 months', 'Praziquantel 80 mg/kg dose only baseline treatment']}

Primary Outcomes:
- {'measure': 'Treatment efficacy', 'description': 'Treatment efficacy as captured by egg reduction rate', 'timeFrame': 'Four weeks post treatment'}
- {'measure': 'Treatment efficacy', 'description': 'Treatment efficacy as captured by cure rate', 'timeFrame': 'Four weeks post treatment'}

Please estimate the sample size based on the assumption: 
Using a two-sided 5% significance level, 80% power requires approximately 173 children per trial arm, and 90% power requires 232 per arm. Allowing for a 7% loss to follow-up, a total of approximately 500 children will be required.
Sample size
        We plan to recruit 600 children into the trial, 300 in Uganda and 300 in the Philippines. The first co-primary outcome will compare cure rate at 4 weeks in the 300 children who received 80âmg/kg PZQ at enrolment compared to the 300 children who received 40âmg/kg PZQ at enrolment. Data from Uganda estimate cure rates for S. mansoni infected 3â9âyears olds of 70% and 82% for 40âmg/kg and 60âmg/kg PZQ, respectively [17]. Using a two-sided 5% significance level, approximately 173 children per trial arm will be required for 80% power and 232 per arm (N = 464) for 90% power to detect a difference in cure rate of 70% versus 82% at 4âweeks between the trial arms. Allowing for loss to follow-up of 7%, a total of approximately 500 children will be required. A sample size of 600 will allow us adequate power to examine sub-groups such as setting/Schistosoma species, younger (12â30âmonths) versus older (30â47âmonths) children, particularly given that cure rates may be lower in younger children and the effect size is likely to be larger based on a higher dose (80âmg/kg).