CNS and Autoimmune Trials: Growth and Operational Implications

In a recent video interview with Applied Clinical Trials, Heidi Chen, Associate Director of Research & Commercial Services at Citeline, discussed findings from the company’s 2025 Annual Clinical Trials Roundup. She outlined how personalized and biomarker-based therapies are creating opportunities and challenges for trial design, especially in rare disease populations, and highlighted the use of historical controls and real-world evidence to support targeted development. She also explained the growth in CNS, autoimmune, and obesity trials, noting the operational implications for study design, site selection, and adoption of decentralized and hybrid trial models. Finally, she discussed how sponsors and CROs are navigating new ICH GCP guidelines while continuing to innovate and maintain data integrity, emphasizing resilience and the ongoing expansion of the clinical pipeline.

The below interview transcript was lightly edited for clarity.

ACT: CNS and autoimmune trials saw double-digit growth last year. What’s driving increased investment in these areas, and how is that shaping study design or site selection?

Chen: Yeah, another great question. In CNS, the growth is dominated by pain trials, and this is because pain is related to so many other diseases and symptoms, whether it's nociceptive or neuropathic. Other CNS disease areas, like depression and Alzheimer's disease, also have some high-profile approvals, so there's revitalized interest in these difficult-to-treat diseases.

Another factor is the increase in the aging population. People are living longer now, and with increased life expectancy, the chances of dementia development can also rise. The paper mentions that the World Health Organization has recognized neurological conditions as the leading cause of ill health and disability worldwide. Mental health has also received more attention in recent years, especially depression, which is a very active area in CNS.

For industry-sponsored trials in autoimmune inflammation therapeutic areas, the dominating indications include atopic dermatitis, asthma, and rheumatoid arthritis. We're also seeing how CAR-T therapies have expanded beyond oncology into this therapeutic area, opening up new grounds, especially in lupus and scleroderma.

Both CNS and autoimmune inflammation trials are top adopters of new technologies, for example, trials that include elements of decentralized clinical trials [DCTs] and protocol designs where clinical endpoints are more amenable to digital technology like wearables. In general, it is more feasible to embrace these technological elements, whether it’s a DCT or hybrid clinical trial approach, compared to a very complex platform trial in oncology. We expect continued uptake of DCTs and creative designs as these two areas continue to grow.