Here is the design of a clinical trial:

Official Title: Oral Switch During Treatment of Left-sided Endocarditis Due to Multi-susceptible Staphylococcus (Relais Oral Dans le Traitement Des Endocardites à Staphylocoques Multi-sensibles)

Included conditions:
- Infective Endocarditis

Study Armgroups:
- {'label': 'Oral switch treatment', 'type': 'EXPERIMENTAL', 'description': 'Oral switch to the combination of levofloxacin and rifampicin', 'interventionNames': ['Drug: Levofloxacin', 'Drug: Rifampicin']}
- {'label': 'Conventional IV treatment according to european guidelines', 'type': 'ACTIVE_COMPARATOR', 'description': 'Conventional IV treatment of staphylococci IE (European guidelines 2015)', 'interventionNames': ['Procedure: Conventional IV treatment of staphylococci IE following European guidelines 2015 including cloxacilline, oxacilline,gentamicine,vancomycine,rifampicine']}

Interventions:
- {'type': 'DRUG', 'name': 'Levofloxacin', 'description': 'levofloxacin 500 mg x1/day (for patients ≤70kg) or levofloxacin 750 mg x1/day (for patients \\>70kg)', 'armGroupLabels': ['Oral switch treatment'], 'otherNames': ['Fluoroquinolones']}
- {'type': 'DRUG', 'name': 'Rifampicin', 'description': 'rifampicin 600mg x1/day (for patients ≤70kg) or rifampicin 900mg x1/day (for patients \\>70kg)', 'armGroupLabels': ['Oral switch treatment']}
- {'type': 'PROCEDURE', 'name': 'Conventional IV treatment of staphylococci IE following European guidelines 2015 including cloxacilline, oxacilline,gentamicine,vancomycine,rifampicine', 'description': 'Conventional IV treatment of staphylococci IE following European guidelines 2015 including cloxacilline, oxacilline,gentamicine,vancomycine,rifampicine', 'armGroupLabels': ['Conventional IV treatment according to european guidelines']}

Primary Outcomes:
- {'measure': 'Treatment failure', 'description': 'Failure is a composite outcome defined by death from all causes and/or symptomatic embolic events and/or unplanned valvular surgery and/or a microbiological relapse (with the primary pathogen).', 'timeFrame': 'up to 3 months after the end of antibiotic treatment'}

Please estimate the sample size based on the assumption: 
A one-sided type I error of 2.5%, a power of 80%, and an expected dropout rate of 10%.
Sample size
        Sample size calculations are based on a null hypothesis of H0: Ï2âÏ1â¥delta (ie, inferior); where Ï1 is the proportion of patients expected to experience failure in the intravenous group, Ï2 is the proportion in the oral switch group, and the non-inferiority margin delta is 10%. The alternative hypothesis is Ï2âÏ1<delta (ie, non-inferior). We considered each pathogen separately to ensure that we will have sufficient statistical power to explore non-inferiority of oral switch for staphylococci as well as for streptococci/enterococci. Thus, for each pathogen, Staphylococcus sp and Streptococcus/Enterococcus sp, we assumed an expected failure proportion of 10%,3 19 20 taking into account the fact that we will only enrol patients who have a favourable outcome after the first 10 days of IE treatment, a non-inferiority margin of 10%, a one-sided type I error of 2.5% and a power of 80%. The number of subjects required is estimated at 145 evaluable subjects per group, thus a total of 290 randomised patients. It is expected that approximately 10% of patients will not be available for the per-protocol (PP) outcome assessment, leading to a total of 324 patients to be enrolled, to be sufficiently powered for the PP analysis. The total required sample size is thus 648 patients: 324 patients for the Staphylococcus sp IE (RODEO 1 trial), and 324 further patients with Streptococcus/Enterococcus sp IE (RODEO 2 trial).