Clinical Trials in Oncology - Key Points to Consider

June 28, 2021

The high biological variability involved in cancer and the stringent regulatory requirements make clinical trials in oncology highly complex. Understanding the challenges at all stages is important to carve out solutions and ensure clinical trial success.

The rising global burden of cancer

Cancer is a major cause of death and reduced life expectancy.\(^1\) As per GLOBOCAN reports, in 2020, there were around 19.3 million new cancer cases worldwide, and 10.0 million people died due to cancer. New cancer cases are estimated to increase to 28.4 million by 2040 – a 47% increase from 2020.\(^2\) These are not just numbers but real human cases - the development of new drugs and treatment regimens for reducing the global disease burden is essential.

Drug developers worldwide are leveraging innovative solutions and a significant amount of resources to find effective cancer therapies. The past few years have seen a rapid increase in the total number of oncology clinical trials.\(^3\) Each trial aims to deliver path-breaking therapies to patients as early as possible and improve their quality of life. 

Unique challenges hindering oncology clinical trials  

Oncology clinical trials can, however, be resource-demanding for both the Investigators and the Sponsor, as they are complex, lengthy, and costly. 

Challenges can range from site selection, regulatory setup to patient recruitment/retention and data collection. Some of the major challenges are discussed below.

1. Patient recruitment

Patient recruitment is the most challenging part of conducting oncology clinical trials.\(^4\) As per published data, less than 5% of adult patients diagnosed with cancer are enrolled in clinical trials.\(^5\)

Patient ineligibility due to narrow study eligibility criteria is one reason for this. Some patients may present with complicated health status with a high risk of developing serious adverse events. Additionally, patient recruitment can be a real challenge for clinical trials involving rare oncology patient populations due to the scarcity and scattered patient population worldwide.     

2. Competing clinical trials

Competing clinical trials is another barrier. In conditions where patients are limited, trials may compete for study participants. Competition can negatively impact the site’s performance and lead to recruitment issues.

3. Varying number of treatment cycles

Another point to be considered in oncology trials is that the number of treatment cycles in cancer usually depends on disease progression or patient’s life expectancy.

4. Complexity of oncology trials

Currently, the majority of oncology trials focus on developing therapies for patients with specific mutations. For this, companies utilize modern trial types such as umbrella trials, basket trials, and adaptive clinical trials in oncology drug development. Compared to traditional trials, these complex trial designs require distinct workflows. These novel trial strategies offer flexibility and efficiency, but increasing trial complexity increases protocol complexity. Complex protocols can generate a large amount of unused data, impact the data quality, and may also increase patient dropout rates. Often, several protocol amendments may be made on a single study, which, in turn, may hamper the trial budget and timelines.

Solutions to overcome challenges - Dokumeds' perspective

1. Effective planning

In oncology trials, the volume of work to ensure patient recruitment, retention, and regulatory requirements are time-consuming and warrants significant expertise in this field. However, effective planning of the clinical trial can save considerable time and help achieve enrolment goals. This may ultimately speed up the availability of new treatments for cancer patients.

2. Involving a Medical Science Liaison

The involvement of a Medical Science Liaison (MSL), also known as enrollment management liaison or clinical medical liaison, in the early phases of trial planning can play a crucial role in ensuring that the research organization runs smoothly.

MSL is a person with project management skills and deep knowledge of the local and international laws and procedures. The MSL holds a key place in conducting the clinical trial.  The work of the MSL will start long before the study is initiated. MSL provides insight to the study teams on best practices for the identification and recruitment of trial subjects. 

3. Feasibility studies

Conducting clinical trial feasibility studies for the smooth execution of the trial is essential. Identifying hurdles early can help save time and money. Site selection should involve identifying the best sites with the right patients and ideally avoiding competing projects. Protocol design and complexity should be carefully scrutinized to ensure feasibility.

4. Adaptive clinical trials in oncology

Modern trial designs such as adaptive trials can be adopted to make drug development more fruitful. Innovative trial designs enable addressing multiple questions together. Adaptive clinical trials in oncology can help identify the best study population, the dosage regimen, and the ideal therapy combinations.

5. Assigning well-experienced staff

Another critical point is the requirement for well-experienced staff. Experienced and trained medical staff is indispensable to manage patients with complicated medical history. The team needs to be well versed with the protocol and study procedures and other requirements.

6. Adopting patient-centric strategies

Patient recruitment and retention can be improved by adopting patient-centric strategies, which include creating patient education materials and tools to improve trial awareness, developing the consent process/materials with the patient in mind, including patient voice and perspectives in protocol design, as well as the implementation of homecare visits

7. Scientific engagement

Scientific engagement with Key Opinion Leaders (KOL) is another focus of MSL. It can help elevate the scientific credibility of the clinical trial during the early phase of planning. The KOL can provide valuable feedback for an efficient clinical trial plan and trial protocol. KOLs can also help investigators in patient enrollment and can advise on the best method for data collection. 

The oversight of the feasibility process and collaboration with KOLs are not the only activities supported by the MSL. MSL also addresses retention aspects of the trial, outlines the existing barriers on the different levels to meet enrolment goals.

Why Dokumeds?

Dokumeds has been conducting oncology projects since 2002. Dokumeds has provided various services in close to 100 oncology projects, including oncology studies involving the paediatric population. 

With a broad operational footprint in 30+ countries in several geographical regions, Dokumeds is one of the leading CROs in oncology research in Europe. Dokumeds' oncology expertise includes Phase I-IV studies with major experience in Phase II and Phase III studies.

Dokumeds has experience working in regions with centralized healthcare systems, which by providing access to a large pool of oncology patients support patient recruitment and lead to successful trial completion.

Dokumeds collaborates with sites that are equipped with the newest technologies, as well as sites that specialize in a given indication. 

For sponsors looking for a reliable partner in oncology research, Dokumeds can be of help. 


  1. Bray F, Laversanne M, Weiderpass E, Soerjomataram I. The ever‐increasing importance of cancer as a leading cause of premature death worldwide. Cancer. In press. Google Scholar
  2. Sung H, Ferlay J, Siegel RL, et al. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries [published online ahead of print, 2021 Feb 4]. CA Cancer J Clin. 2021;10.3322/caac.21660.
  3. Global Oncology Trends 2019. Iqvia. 2019. Available at: https://www.iqvia.com/insights/the-iqvia-institute/reports/global-oncology-trends-2019. Accessed on: 28 April 2021. 
  4. Busting Patient Recruitment Bottlenecks in Oncology Trials. Applied Clinical Trials. 2020. Available at: Busting Patient Recruitment Bottlenecks in Oncology Trials. Accessed on: 28 April 2021.
  5. Unger JM, Cook E, Tai E, Bleyer A. The Role of Clinical Trial Participation in Cancer Research: Barriers, Evidence, and Strategies. Am Soc Clin Oncol Educ Book. 2016;35:185-198. 

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