Multiple Eligibility Criteria: Inclusion Criteria: Modern day Cancer Clinical Trials look at specific information about primary cancer, stage of disease, cell type, genetic or molecular profile before trial enrolment. Molecular profiling is particularly vital before enrolment into Precision Medicine Clinical Trials. The required depth of information adds a layer of complexity which makes it increasingly challenging for patients to find relevant trials and likewise for trial sponsors to find the right patients for clinical trials. 

Multiple Eligibility Criteria: Exclusion Criteria: Given the poor historical prognosis of most cancers, trial sponsors have generally aimed to select the healthiest cancer patients for clinical trials. While this is slowly anticipated to change to allow for a broader and more representative group of patients, many trials still require patients to meet criteria such as: having no existing issues with their heart, liver or kidney function; having no brain involvement with cancer; nor infectious diseases which may theoretically place them at a higher risk of treatment-related complications. In this day of Immunotherapy drug development, clinical trials approaching such therapies typically require patients to have well-controlled or no active autoimmune-related conditions in addition to other requirements. These specific criteria add much complexity in the design, enrolment of patients and conduct of cancer clinical trials in comparison to clinical trials for other conditions.

The Use of Placebos in Cancer Clinical Trials : A Placebo is a Pill, Injection or Treatment that has neither any beneficial nor any adverse effect on the Trial patient. Trial Designs called Comparative Trials are sometimes used in Phase III Cancer Trials. Rarely, when there are no standard treatments available for the particular cancer type and stage, the New Treatment is compared with a Placebo. In all cases where Standard Treatments are available, the New Treatment is compared with the Standard Treatment.

Measurable Disease in Solid Tumours : One objective of a Cancer Clinical Trial is to evaluate whether or not the New Treatment is effective in curing or controlling the particular Cancer type or Stage. This objective typically requires researchers to begin with detecting a Cancer lesion in a specific organ, document its measurements at the start of the trial and follow up with the changes to the size of the lesion in follow up scans. The lesion that is assessed needs to have measurable dimensions. The presence of Measurable Disease or Lesions in a Cancer patient’s body is an important Eligibility Criterion in many Cancer Trials. Cancers involving unique parts of the body such as the peritoneum and meninges may not be measurable and patients with cancer limited to such sites may be excluded from cancer clinical trials.

Longer Evaluation Period : The Clinical Trial evaluation of the Effectiveness of New Treatments for Cancer is also a challenging process. This challenge means a more extended Evaluation Period. Many of the Cancer Evaluation Endpoints like Response, Progression or Survival after the treatment have to be measured over many months or sometimes even a few years. Consequently, the longer Evaluation Periods result in longer Overall Trial durations. Global Regulatory bodies and Researchers are aware of this challenge. Through Innovative Trial Designs, in-built mechanisms can ensure that patients are not subjected to any unnecessary risk or inconvenience due to the long follow up periods.