Since June the number of total disrupted trials has begun to fall, as shown in Figure 1. The majority of clinical trial disruption currently is due to the suspension of enrolment, followed by trials impacted due to slow enrolment, and then finally, trials that have delayed initiation. However, although the total number of disrupted trials is decreasing overall, within these categories only trials that suspended enrolment have been on a downward trajectory. Clinical trials that delayed initiation have remained steady and trials that have been impacted by slow enrolment have continued to increase. This suggests trials that had already initiated enrolment before the pandemic, with chosen sites and investigators, but then suspended due to Covid-19, are having more success picking up where they left off as long as enrolment wasn’t impacted. Within the category of trials currently affected by slow enrolment, one-tenth of these are specifically due to the availability of sites and investigators. Many hospitals that serve as trial sites were inundated with Covid-19 patients and may still not be available. For that same reason, many investigators may be repurposed to Covid-19 drug discovery trials or treating Covid-19 patients, or activation of sites for non-Covid-19 trials are being deprioritised. As the number of trials that have been impacted by slow enrolment has increased by 13.9%, this seems to continue to be an issue. Trials that have delayed initiation altogether have also increased by 10% compared to last month. Besides the issue just mentioned, there is also a high risk to subjects in a clinical trial who have serious chronic or acute condition that affects their immune system, giving them a greater chance of contracting Covid-19 and making them not willing to enrol in a clinical trial.
Figure 1: Clinical Trials Disruption
The overwhelming majority of trial sites that are currently disrupted are located in the US, at 43.6%. This is followed by the UK at 7.9% of all sites and Spain at 5.6%. The US is seeing peak numbers of confirmed Covid-19 cases since the pandemic in certain states. The highest numbers of site disruptions are found in California at 10%, followed by Florida at 9.7% and Texas at 8.9%, and all three states recently saw spikes in confirmed cases. New York, where the pandemic initially hit the hardest, comes in fourth at 5.8%.
Figure 2: Clinical Trials Resumptions
The FDA has issued guidance for industry, investigators, and institutional review boards on conducting clinical trials during the Covid-19 pandemic. Methods that could help keep the research going or get started include virtual visits, phone interviews, self-administration, and remote monitoring. These suggestions could help trials that are being met with subject quarantine and travel limitations, clinical site closures, and interrupted supply chains, especially trials that delayed initiation and trials that have been impacted by slow enrolment. Importantly, the total number of disrupted trials is falling and the number of clinical trials that have resumed continues to rise (Figure 2). This implies that sponsors and contract service providers have begun to adjust clinical trial design strategies and are adapting to the new post-Covid-19 environment.