Here is the design of a clinical trial:

Official Title: A "negative"dendritic Cell-based Vaccine for the Treatment of Multiple Sclerosis: a First-in-human Clinical Trial

Included conditions:
- Multiple Sclerosis

Study Armgroups:
- {'label': 'tolerogenic dendritic cells (tolDC)', 'type': 'EXPERIMENTAL', 'description': 'Each vaccine (5x106, 10x106 , or 15x106cells in 500 µL NaCl 0.9% solution supplemented with 5% human albumin) will be administered through intradermal injection at 5 sites (100 µL/site) in the subclavicular region (5-10 cm from the cervical lymph nodes). Injection sites will alternate between left and right sides.', 'interventionNames': ['Biological: tolerogenic dendritic cells (tolDC)']}

Interventions:
- {'type': 'BIOLOGICAL', 'name': 'tolerogenic dendritic cells (tolDC)', 'description': 'dose-escalation', 'armGroupLabels': ['tolerogenic dendritic cells (tolDC)']}

Primary Outcomes:
- {'measure': 'Safety (Occurrence and severity of adverse events will be recorded)', 'description': 'Occurrence and severity of adverse events will be recorded', 'timeFrame': '6 months'}
- {'measure': 'Feasibility (Generation of GMP-grade cell product released according to QC)', 'description': 'Generation of GMP-grade cell product released according to QC', 'timeFrame': '6 months'}

Please estimate the sample size based on the assumption: 
Dose escalation decisions are made after 3 months of follow-up for all subjects in the cohort, with safety and tolerability analyses reviewed by investigators and the independent Data Safety Monitoring Board (DSMB). The trial terminates if three or more DLT are observed.
Determination of sample size and dose-escalation procedure
          The studies will be conducted according to a âbest of fiveâ design,41 an alternative of the traditional 3+3 design in that one additional patient is added when one or even two dose-limiting toxicities (DLT) are observed among the first three patients. Another patient is added when two DLT are observed among four treated patients. Dose escalation is allowed if DLT are observed among none of three, one of four or two of five patients, but the trial will terminate if three or more DLT are observed. A DLT is defined as a serious adverse event (SAE) that is attributable to the study cells administered, or of which the severity prevents further escalation. Dose escalation decisions will be made after all subjects in the cohort have completed at least 3 months of follow-up and when the results of the safety and tolerability analyses of the preceding dose regimen are satisfactory in the judgement of the investigators and the independent Data Safety Monitoring Board (DSMB).
          An overview of the dose escalation is provided in table 3. Altogether, each phase I study is intended to accrue a total number of 9â15 evaluable patients.
          
            Table 3
            
              Outline of the cell doses and patient numbers, per phase I clinical trial, in the dose escalation cohorts for intradermal and intranodal administration of tolDC
            
            
              
                
                  Cohort
                  Treatment regimen
                  Patient numbers
                
              
              
                
                  1
                  6 i.d./i.n. injections of 5Ã106 tolDC
                  N=3 (+1+1)
                
                
                  2
                  6 i.d./i.n. injections of 10Ã106 tolDC
                  N=3 (+1+1)
                
                
                  3
                  6 i.d./i.n. injections of 15Ã106 tolDC
                  N=3 (+1+1)
                
              
            
            
              
                N, number; i.d., intradermal; i.n., intranodal; tolDC, tolerogenic dendritic cells.