Here is the design of a clinical trial:

Official Title: Recombinant Human C1 Esterase Inhibitor (Conestat Alfa) in the Prevention of Severe SARS-CoV-2 Infection in Hospitalized Patients With COVID-19: a Randomized, Parallel-group, Open-label, Multi-center Pilot Trial (PROTECT-COVID-19).

Included conditions:
- Coronavirus Infections

Study Armgroups:
- {'label': 'active treatment arm', 'type': 'ACTIVE_COMPARATOR', 'description': 'treatment with conestat alfa in addition to standarf of care', 'interventionNames': ['Drug: Conestat alfa']}
- {'label': 'Standard of care treatment arm', 'type': 'NO_INTERVENTION', 'description': 'Standard of care treatment established at the centers'}

Interventions:
- {'type': 'DRUG', 'name': 'Conestat alfa', 'description': 'Conestat alfa (8400 Units (U) followed by 4200 U every 8 hours, 9 administrations in total) will be administered as a slow intravenous injection (5-10 minutes) over a 72 hour period.', 'armGroupLabels': ['active treatment arm']}

Primary Outcomes:
- {'measure': 'Disease severity', 'description': 'Disease severity on the 7-point Ordinal World Health Organization (WHO) scale (for the current study, score 0 will be omitted and score 6 and 7 will be combined). The ordinal scale measures illness severity over time. This endpoint has been suggested by WHO for clinical trials in patients with COVID-19.', 'timeFrame': 'on day 7'}

Please estimate the sample size based on the assumption: 
Two interim analyses after 40 and 80 patients with Pocock adjusted levels αp = 0.0221.
Numbers to be randomised (sample size)
          We will randomise approximately 120 individuals (80 in the active treatment arm, 40 in the SOC group). Two interim analyses after 40 and 80 patients are planned according to the Pocock adjusted levels Î±p = 0.0221. The results of the interim analysis will allow adjustment of the sample size (Lehmacher, Wassmer, 1999).