Clinical Trial Starts Rose At Slower Pace In 2024

By Shannon Fisher Associate Director, Oncology; and Heidi Chen Associate Director, Research & Commercial Services

The past year brought a complex mix of scientific, geopolitical, and regulatory shifts that reshaped the clinical research landscape. In 2024, the industry continued to adjust to the post-pandemic decline in COVID-19 trials while contending with new and ongoing geopolitical conflicts — including the Israel–Hamas war and the sustained Ukraine–Russia conflict — as well as a change in U.S. political leadership and evolving policy priorities.

Regulatory expectations also continued to influence trial design, with global authorities reinforcing requirements for diversity, equity, and inclusion (DE&I) and calling for broader representation across race, sex, gender identity, and geography. At the same time, artificial intelligence (AI) and machine learning gained meaningful traction as practical tools supporting recruitment, data review and sharing, and adaptive trial design.

Following the structure of previous editions, this year’s analysis reviews Phase 1-3 clinical trials initiated in 2024 across therapeutic areas (TAs), diseases, sponsors, and geographies. As of June 2025, Trialtrove identified 10,503 Phase 1-3 trials (Table 1) evaluating at least one drug with a disclosed 2024 start date.

Overall, trial initiations rose 5.5% from 2023 to 2024 — an increase, though not as substantial as the 9.4% growth seen from 2022 to 2023. Industry-sponsored studies, which account for 67% of all trial starts, followed a similar pattern with a 3.6% rise in 2024, down from 11% growth the prior year. This moderation is notable, as industry-driven trials remain a key engine of clinical research activity.