Company lists · Data refreshed September 2026
Top 25 Investigator-initiated trial sites worldwide
RevenueBase identified 1,585 investigator-initiated trial sites worldwide as of September 2026 and tracks 66,208 professional contacts across them, including 25,823 with verified work emails. The United States is the largest market and Miami the largest hub.
This list covers investigator-initiated trial sites worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 20, 2026. Country and city lists for investigator-initiated trial sites follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest investigator-initiated trial sites worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 20,530 contacts → | ||||
Indirect evidence “The PPD™ clinical research business of Thermo Fisher Scientific, the world leader in serving science, enables customers to accelerate innovation and drug development through…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 2 | 4,708 contacts → | ||||
Indirect evidence “PRA is now an ICON plc company.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 3 | 1,778 contacts → | ||||
Indirect evidence “Novotech is a globally recognized full-service clinical research organization (CRO) and scientific advisory company that provides biotech and small- to mid-sized pharma companies…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 4 | 1,080 contacts → | ||||
Indirect evidence “Celerion, a leader in early clinical research, delivers Applied Translational Medicine.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 5 | 1,043 contacts → | ||||
Partial evidence “CTI Clinical Trial and Consulting Services is a global, privately held, research service organization, delivering a complete spectrum of clinical trial and consulting services…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 6 | 971 contacts → | ||||
Partial evidence “Velocity is the world’s leading organization of fully integrated clinical research sites.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 7 | 868 contacts → | ||||
Partial evidence “Sarah Cannon Research Institute (SCRI) is one of the world’s leading oncology research organizations, conducting community-based clinical trials.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 8 | 847 contacts → | ||||
Indirect evidence “CenExel is a leading integrated, wholly owned, nationwide clinical research site network comprised of 18 Centers of Excellence in major metropolitan areas across the U.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 9 | 758 contacts → | ||||
Indirect evidence “Caidya is a multi-therapeutic clinical research organization (CRO) serving innovators worldwide.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 10 | 590 contacts → | ||||
Strong evidence “DM Clinical Research is a network of clinical trial investigator sites with headquarters based out of Houston, Texas.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 11 | 575 contacts → | ||||
Partial evidence “Nucleus Network is the only global provider dedicated to early phase clinical trials, with units in Australia, the USA and the UK.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 12 | 568 contacts → | ||||
Indirect evidence “Pharma Medica Research is a full service early phase contract research organization.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 13 | 535 contacts → | ||||
Indirect evidence “AXIS Clinicals Limited is one of the most experienced and fastest growing Clinical Research Organization.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 14 | 532 contacts → | ||||
Indirect evidence “THIS PAGE IS NOT MONITORED.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 15 | 389 contacts → | ||||
Indirect evidence “Sitero is a next-generation, site-focused clinical research organization (CRO) for life sciences and institutional research organizations that helps get treatments to market safer…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 16 | 386 contacts → | ||||
Indirect evidence “Avance Clinical is a full-service Contract Research Organization (CRO) headquartered in Australia, with extensive operations across New Zealand, Asia, North America, and Europe.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 17 | 367 contacts → | ||||
Indirect evidence “The CRO for data-intensive, early phase clinical studies.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 18 | 333 contacts → | ||||
Partial evidence “MAC Clinical Research is a leading full-service, global Contract Research Organisation (CRO) with over 30 years of experience in clinical trial management.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 19 | 321 contacts → | ||||
Partial evidence “Flourish Research is a fully integrated, multi-site clinical trial network serving sponsors and CROs across North America.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 20 | 312 contacts → | ||||
Partial evidence “Pratia Research Site Network, owns and commands a network of over 100 clinical research sites, establishing strong presence across 9 countries globally.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 21 | 308 contacts → | ||||
Partial evidence “MEDEX is an organization that specializes in managing clinical research sites.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 22 | 295 contacts → | ||||
Strong evidence “Florence is a purpose-built platform that connects sponsors and sites to accelerate clinical trials, improve operational capacity, and reduce risk.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 23 | 291 contacts → | ||||
Partial evidence “Science 37 is a modern clinical research site that delivers trials directly to patients’ homes.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 24 | 282 contacts → | ||||
Partial evidence “FutureMeds is an independent, fully-owned European Site Network and DCT service provider dedicated to running patient-centric clinical trials and delivering quality data for the…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 25 | 264 contacts → | ||||
Partial evidence “Accellacare delivers clinical trial services to pharmaceutical, biotechnology, medical device industries.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: investigator-initiated trial sites. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names investigator-initiated trial sites.
- Partial evidence
- Its own public description names part of investigator-initiated trial sites, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name investigator-initiated trial sites. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 1,585 investigator-initiated trial sites worldwide
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Investigator-initiated trial sites worldwide at a glance
As of Sep 20, 2026Companies by employee count
Email recency is reported on each country list linked below.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among investigator-initiated trial sites, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- Coverage
- Every country. Country and city lists for investigator-initiated trial sites are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “investigator-initiated trial sites”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names investigator-initiated trial sites), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among investigator-initiated trial sites, and records with no verified work email.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 25,823 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 20, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Investigator-initiated trial sites by location
6 lists · largest firstEvery Investigator-initiated trial sites list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Investigator-initiated trial sites based in the United States816
- Investigator-initiated trial sites based in India66
- Investigator-initiated trial sites based in the United Kingdom57
- Investigator-initiated trial sites based in Poland52
- Investigator-initiated trial sites based in Australia50
- Investigator-initiated trial sites based in Canada38
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names investigator-initiated trial sites, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many investigator-initiated trial sites are there worldwide?
RevenueBase identified 1,585 investigator-initiated trial sites worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
PPD, headquartered in Waltham, tops this list with the largest team on record.
Which country has the most investigator-initiated trial sites?
The United States leads with 816 companies, followed by India (66) and the United Kingdom (57). Every investigator-initiated trial sites list by country and city is linked on this page.
Which city has the most investigator-initiated trial sites?
Miami leads with 50 headquartered companies, followed by Houston (25) and London (18).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 25,823 verified decision-maker contacts tracked across these 1,585 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 20, 2026.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.