Top Clinical Trial Companies (CROs) Globally based on Q2 2025 Revenue
Clinical trial services have become integral to the healthcare industry. Ever since the Covid-19 pandemic, pharmaceutical companies have realised the importance of keeping up with diseases and finding timely cure and medication.
The global clinical trials services market size was valued at USD 76.70 billion in 2024 and is projected to reach USD 132.05 billion by 2033, exhibiting a CAGR of 6.3% during the between 2025-2033. Pharma outsourcing for the working of a drug to clinical trial service companies in order to gain approval from regulatory agencies is integral for any frug to make it to the market and is seeing a sudden boom.
Global clinical trial activity by country in 2024
As of 2024, USA has the highest number of clinical trials globally leading with a total of 186,497 clinical trials. China came in second with 135,747 clinical trials occurring in 2024. India occupied the third rank with a total of 74,031 clinical trials.
Japan another Asian country dominating the clinical trial scene had 65,167 clinical trials. Europe’s entry into the top 10 list was made with Germany ranking 5th globally as it had 54,902 clinical trials occurring in 2024. United Kingdom also made the list with 49,145 clinical trials.
Other European countries such as France and Netherlands also ranked in the list, with clinical trials amounting to 46,309 and 43,304 respectively. Spain also made it to the list for a total of 33,767 clinical trials.
Middle East also created a space for itself by with Iran responsible for 40,245 clinical trials. Canada accounted for 35,700 clinical trials while Australia followed with 32,924 clinical trials. Brazil came in last with total number of clinical trials being 20,765.
Leading clinical trial service companies
In Q2 2025, leading Clinical trial companies demonstrated both resilience and growth in spite of mixed market conditions.
- Thermo Fisher Scientific (PPD Division)led the pack with $6 billion in revenue, highlighting its scale as one of the largest global clinical trial service organisations.
- IQVIA followed with $4.02 billion up by 5.3% YoY, supported by a significant $32.1 billion backlog in contracts with predictions of $8.1 billion of the backlog to be converted to revenue by June 2026.
- ICON plc reported $2.02 billion, a slight YoY dip offset by improved earnings.
- China-based WuXi AppTec ($2.87 billion) and Pharmaron ($888 million) remained central to Asia’s expanding biotech economy, while Charles River Laboratories ($1.03 billion) maintained its dominance with strong preclinical services.
- Rounding out the list, Fortrea ($710 million) continued to stabilize and Medpace delivered standout growth with $603 million in revenue and a 14.2 % YoY increase.
Regionally, the U.S. remains the engine of CRO growth, fueling results for IQVIA, ICON, and Medpace, while China and India’s high trial volumes provide momentum for WuXi and Pharmaron. Europe also plays a steady role, with ICON and Charles River benefiting from consistent activity in Germany, the U.K., and France.
Conclusion
Clinical trial service companies continue to help in advancing global healthcare. With the U.S. leading in trial activity and Asia rapidly expanding, companies like Thermo Fisher, IQVIA, ICON, and Medpace are well positioned for growth. The sector is gaining investor confidence, with strong backlogs, favourable book-to-bill ratios, and surging CRO stocks.
