Here is the design of a clinical trial:

Official Title: A Phase II Study Assessing Safety and Efficacy of Cabozantinib for Advanced or Metastatic Cervical Carcinoma After Platinum Treatment Failure

Included conditions:
- Advanced/Metastatic Cervical Cancer

Study Armgroups:
- {'label': 'CABOZANTINIB', 'type': 'EXPERIMENTAL', 'description': 'Cabozantinib will be administered at the daily dose of 60 mg given orally in a 4-week cycle. It will be continued without interruption until disease progression or discontinuation for any cause.', 'interventionNames': ['Drug: Cabozantinib']}

Interventions:
- {'type': 'DRUG', 'name': 'Cabozantinib', 'description': 'Cabozantinib will be administered at the daily dose of 60 mg given orally in a 4-week cycle. It will be continued without interruption until disease progression or discontinuation for any cause.', 'armGroupLabels': ['CABOZANTINIB']}

Primary Outcomes:
- {'measure': 'efficacy of cabozantinib: proportion of patients with disease control rate', 'description': 'Efficacy assessed by the proportion of patients with disease control rate', 'timeFrame': '3 months after cabozantinib treatment initiation.'}
- {'measure': 'Safety of cabozantinib: proportion of patients with clinical gastro-intestinal (GI) perforation/fistula, GI-vaginal fistula and genito-urinary (GU) fistula events grade ≥ 2 (NCI CTCAE v 5.0)', 'description': 'Safety assessed by the proportion of patients with clinical gastro-intestinal (GI) perforation/fistula, GI-vaginal fistula and genito-urinary (GU) fistula events grade ≥ 2 (NCI CTCAE v 5.0)', 'timeFrame': 'toxicities occurring up to 1 month after the end of treatment'}

Please estimate the sample size based on the assumption: 
Alpha risk of 5% for efficacy, 10% for toxicity, power of 80%, and a 10% drop-out rate.
Sample size calculation
          We plan to use a single arm two-stage multicenter phase II trial based on a Bryant-and-Day design, selected in order to simultaneously assess efficacy and safety and to minimize the expected number of patients treated in case of insufficient efficacy and/or safety of cabozantinib monotherapy.
          In accordance with literature estimating a median PFS around 3.4âmonths for advanced cervical cancer patients under bevacizumab monotherapy and 4âmonths for pazopanib, the null hypothesis for efficacy is a 3-month disease control rate of 30% and we expect a rate of 50% to conclude to efficacy of cabozantinib [11, 30].
          Toxicity, defined as clinical significant (gradeââ¥â2 NCI CTCAE version 5) fistula and perforation rate, will be considered as acceptable if it concerns at most 10% of patients and intolerable if it exceeds 25%.
          According to these hypotheses, considering an alpha risk of 5% for efficacy and 10% for toxicity and a power of 80%, assuming a 10% drop-out rate, 57 patients are required in this study (25 for the first stage and 32 additional for the second stage).
          Especially, 22 assessable patients will be included in the first stage. If disease control is observed in less than 8 patients at 3âmonths or if more than 4 patients experiment fistula or perforation, the study will be stopped at the interim analysis to conclude to insufficient efficacy or unacceptable toxicity of Cabozantinib. Eventually, observation of a minimum of 21 patients with disease control with less than 9 patients with toxicity will allow to conclude to efficacy and tolerance.
          To be noted, enrolment were not initially planned to be halted to conduct the interim analysis. However, due to the quickness of recruitment in the study, the protocol was amended to suspend the inclusions to perform the interim analysis, in order to have a sufficient perspective on the tolerance and efficacy of Cabozantinib single-agent treatment.