Why do rare disease clinical trials face greater challenges and what are some solutions?

Over 6,800 rare diseases such as Haemophilia, Tay Sach’s disease and Gaucher disease are affecting more than 25 million Americans. Still yet, there is limited understanding or knowledge of these debilitating, life threatening and progressive diseases. The Orphan Drug Act defines rare diseases as disorders affecting less than 200,000 people in the United States. Such a small patient population is the exact cause of problems and challenges in patient enrolment.

One requirement for the study of human diseases is an appropriate trial design. Randomization and control are considered essential if efficacy is to be attained and bias to be reduced, but for this a large sample must be acquired. However, due to scattered patient populations, variations among disease sub types and simply by necessity, clinical trials in rare diseases enrol small samples and still yet with difficulty.

This is partly due to the fact that the majority of rare diseases affect children and reduce lifespan. This leads to families being less likely to enrol their child into a study in which they may receive a placebo. Ethical issues may arise too as children are considered a ‘vulnerable’ population. In addition, problems occur if several studies are being carried out simultaneously as enrolment of a patient in one study may cause illegibility in another. As a result of enrolment challenges, it’s calculated that approximately 30% of phase III trials in rare diseases fail.

Clearly, rare diseases require an approach that is tailored to the study goal and specific indications. Two solution that are arguably vital are: in-home Clinical Trial Support and Patient Registries.

In-home Clinical Trial Support

Traditionally, patients are faced with the inconveniency of traveling to sites numerous times during the study. This puts strain on the patients’ budget and induces drop-outs. In-home Clinical Trial Support however takes into account the patients preferences and difficulties. The nurses travel to the patients’ home instead to carry out the clinical tests, PK sampling, drug infusion administration etc. This saves the patients major costs in regards to accommodation and reduces the number of visits to the sites making the concept of enrolment more appealing.

Patient Registries

With rare diseases it is often the case that sufficient data or information is unavailable. Patient registries help improve understanding and expand the knowledge base for companies developing treatments. Patient registries are global online data-repositories encompassing patients’ treatment-related health information which are created by several nations such as the U.S and Europe. They allow the development of communities which are able to share information regarding clinical trials which in turn increases the rate of patient recruitment, reduces enrolment delays, and allows better site planning as wider knowledge on the subject is made available.

The current status in regards to rare diseases is that we have a significant knowledge gap. In order to reduce this, continued collective efforts must be made to improve the clinical trial protocol design which will ultimately reduce time delays, hasten patient recruitment and most importantly, benefit those suffering from rare diseases.


Augustine, Erika F., Heather R. Adams, and Jonathan W. Mink. “Clinical Trials in Rare Disease: Challenges and Opportunities.” Journal of child neurology28.9 (2013): 1142–1150. PMC. Web. 9 June 2017.

Khaleel, Samiya. “Rare Disease Patient Recruitment And Retention.” Clinical Leader. N.p., n.d. Web. 8 June 2017.

Leavy, Michelle, and Richard Gliklich. “Patient Registries and Rare Diseases.” Applied Clinical Trials. N.p., 2011. Web. 8 June 2017.

Stevenson, Danielle. “Clinical Trials for Rare Diseases – Finding and Keeping Patients.” BHD Foundation. N.p., n.d. Web. 8 June 2017.

Tirunagari, Sreedhar. “Rare Disease Clinical Trials‘Patient Recruitment Challenges.’” Global Health Trials. N.p., n.d. Web. 8 June 2017.

Anna Nikitina

This entry was posted in Patient Enrolment, Rare Diseases. Bookmark the permalink.

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