Over the span of a decade, there is no significant relative rise in the number of clinical trials focusing on Indigenous Australians in relation to Australia-based trials on the general population, researchers say.

This is despite there being an increase in the Australian National Health and Medical Research Council (NHMRC) funding for Indigenous health-related research. According to a BMC Public Health study released on May 14, funding for such trials increased from 2.9% in 2006 to 6.3% in 2015.

Some 9,206 clinical trials were included in the analysis, with 139 (1.5%) focusing on Indigenous health. There is no relative increase in Indigenous trials over the ten years between 2008 and 2018 (p = 0.30).

A possible reason for this is that there could be an increase in participation among Indigenous Australians in studies conducted in the general Australian population. Another potential reason is that Indigenous-Australian trials now have a larger median sample size. This could mean that such trials are now larger and are more expensive to run, limiting the number of studies, researchers say.

In January, Clinical Trials Arena released an exclusive data-led analysis showing how Australia’s clinical trials sector has been largely protected from the pandemic due to the country’s zero-Covid approach.  

Indigenous Australian trials mostly public health studies

Trials specific to Indigenous Australians tend to be mostly on public health-relevant topics, such as screening and preventive interventions. These studies are also more commonly sponsored by universities and the government.

Indigenous-Australian trials are also less likely to be blinded in design, potentially due to a high focus on “participatory style of research”. This is to encourage collaboration between researchers and participants. Public health, education, or screening-related research are also more challenging to blind.

As for diseases, the high number of mental health and cardiovascular disease trials in Indigenous Australians is in line with the most common issues seen in this population. However, diseases such as cancer and musculoskeletal illness need more research in the Indigenous Australian population as incidences are high.

Using clinical trial registry data, researchers reviewed registered studies on the health of Indigenous Australians compared with general Australia-based trials between 2008 and 2018. The research team used search terms relevant to Indigenous-Australian trials, which were studied by two independent reviewers plus an Indigenous researcher. 

Diversity a hot topic in clinical trials

Broadly speaking, boosting diversity within and among studies is a hot topic in clinical trials regardless of where they are run. A broad scope would represent how therapies or interventions could perform in a real world setting and in specific subpopulations where the need is greatest.

In the US, for example, the FDA issued a new draft guidance to the pharma industry on how to develop plans for enrolling more subjects from underrepresented racial and ethnic populations in the US. While certain countries like China are attractive to run clinical trials from, the agency also takes issue with data collected from overseas that does not reflect the diversity of the US. 

Decentralised clinical trials are designed to potentially bolster engagement with a wider range of clinical trial patients by making participation more convenient. That said, the industry needs to be cognizant that diversity is a multidimensional factor that needs to be integrated in clinical trials, as this should cover race, education, gender, among others, not just any of these singular elements.