Here is the design of a clinical trial:

Official Title: Safety and Efficacy of High Dose Inorganic seLenium for Preventing Chemotherapy Induced pEripheral Neuropathy in platINUM Sensitive Recurrent Ovarian, Fallopian, Primary Peritoneal Cancer: Phase III Randomised Controlled Trial

Included conditions:
- Chemotherapy-induced Peripheral Neuropathy
- Recurrent Ovarian Carcinoma
- Ovarian Cancer
- Fallopian Tube Cancer
- Primary Peritoneal Carcinoma

Study Armgroups:
- {'label': 'Experimental group', 'type': 'EXPERIMENTAL', 'description': 'The patient will receive an intravenous selenium 2000 μg/40 ml dose just before chemotherapy begins every cycle (every 3 weeks for 6 cycles). Afterward, the same dose will be continued during the maintenance period if it is medically required or if the patient desires to do so.', 'interventionNames': ['Drug: sodium selenite pentahydrate', 'Drug: Chemotherapy']}
- {'label': 'Placebo group', 'type': 'PLACEBO_COMPARATOR', 'description': 'The patient will receive an intravenous normal saline 40 ml dose just before chemotherapy begins every cycle (every 3 weeks for 6 cycles). Afterward, the same dose will be continued during the maintenance period if it is medically required or if the patient desires to do so.', 'interventionNames': ['Drug: Normal saline', 'Drug: Chemotherapy']}

Interventions:
- {'type': 'DRUG', 'name': 'sodium selenite pentahydrate', 'description': 'High-dose inorganic selenium (2000 μg/40 ml) will be administered before chemotherapy in patients assigned to the experimental group.', 'armGroupLabels': ['Experimental group'], 'otherNames': ['Selentab inj. A12CE02']}
- {'type': 'DRUG', 'name': 'Normal saline', 'description': 'Normal saline (40 ml) will be administered before chemotherapy in patients assigned to the control group.', 'armGroupLabels': ['Placebo group'], 'otherNames': ['sodium chloride 0.9%']}
- {'type': 'DRUG', 'name': 'Chemotherapy', 'description': 'Paclitaxel (175mg/m2), carboplatin (AUC 5.0 or 6.0) IV, and bevacizumab IV (15mg/kg) D1, every three weeks.', 'armGroupLabels': ['Experimental group', 'Placebo group'], 'otherNames': ['Paclitaxel, carboplatin and bevacizumab']}

Primary Outcomes:
- {'measure': 'Incidence of chemotherapy-induced peripheral neuropathy (3m)', 'description': 'To evaluate the incidence of CIPN by evaluating paresthesia, pain and motor based on WHO-CIPN criteria.', 'timeFrame': 'Examined at 3 months after last paclitaxel chemotherapy'}

Please estimate the sample size based on the assumption: 
80% power, significance level of 0.05, 80% completion rate for six cycles, and an additional dropout rate of 10%.
SAMPLE SIZE JUSTIFICATION
      In previous studies, the incidence rate of CIPN was 25% when combined with antioxidants [19], whereas it was at least 62.5% without antioxidants three months after chemotherapy using paclitaxel or cisplatin [20]. We expect that 25% of patients will develop CIPN when treated with selenium and chemotherapy, while 62.5% of patients in the control group will develop CIPN. Group sample sizes of 24 in each group are needed to achieve 80% power to detect a difference between the group proportions of â0.37, and the test statistic used is the two-sided Z-Test with unpooled variance, and the significance level of the test is 0.05. However, to evaluate the effect of selenium on the prevention of CIPN, the proportion of patients who can complete six cycles of chemotherapy using paclitaxel, carboplatin, and bevacizumab should be maintained above the lowest proportion. In the Gynecologic Oncology Group (GOG)-213 study, the percentage of patients who completed the planned 4â6 cycles was found to be 85.8% [15]. Therefore, a total of 68 cases, comprising 34 cases per group, is required to evaluate the efficacy of selenium administration, to assume 80% of completion rate for six cycles with consideration of the additional dropout rate of 10%.