What is cost per enrollee for clinical trials?
Cost per enrollee is reported trial spend divided by enrollment: the per-patient benchmark that makes a 42-person phase 1 comparable to a phase 3.
Cost per enrollee is a clinical trial's reported spending divided by the number of patients enrolled. In our data that means disclosed industry research payments for a trial, divided by its enrollment from ClinicalTrials.gov.
Why per-patient beats per-trial
In the disclosed payment data, the median phase 1 trial cost is about $455K and the median phase 3 cost is about $463K. By totals, the phases appear to be the same, but per enrollee, they are nothing alike.
The median phase 1 trial got there with 42 patients; while the phase 3 spread similar dollars across hundreds of patients. Per enrollee, phase 1 comes to $10.6K and phase 3 to $2.1K, five times apart. Cost per enrollee is what makes a tiny first-in-human study and a sprawling outcomes trial comparable.
What counts as the numerator
In DealHub's clinical trial data, the numerator is the research payments sponsors disclosed to CMS for US physicians and teaching hospitals, summed per trial. That makes every cost-per-enrollee figure a floor. CRO fees, non-US sites, drug supply and academic funding never enter the numerator, so the full per-patient cost of a trial sits well above its disclosed figure. What the disclosure data captures and misses is laid out in where the data comes from.
The denominator is reported enrollment, which is target enrollment for some ongoing studies. A trial that enrolls short of target will look cheaper per enrollee than it was.
Typical values
Across 5,413 US trials, the median disclosed figure is $2,906 per enrollee, with a 25th percentile of $435 and a 75th percentile of $11K. Phase is the most important descriptive factor: $10.6K at phase 1, $4.0K at phase 2, $2.1K at phase 3, $2.7K at phase 4. Therapeutic area is a close second, with cardiometabolic at the top of phase 1 and infectious disease at the bottom of phase 3. Full tables by phase and area are in cost per patient by phase, and the market-wide picture is in what a clinical trial costs.
Common questions
Is cost per enrollee the same as cost per patient? The terms get used interchangeably. Enrollee is the precise word because it counts people enrolled in the trial, whether or not they complete it, and enrollment is the figure trial registries publish.
What is a good cost per enrollee? There is no single good number, only context. Benchmark a trial against its own phase and therapeutic area: a $10K figure is unremarkable for phase 1 and roughly five times the phase 3 median.
Data notes
Figures come from CMS Open Payments research payment records matched to ClinicalTrials.gov by NCT number 2020–2024 (January 2026 file release). Cost per enrollee is disclosed payments divided by reported enrollment. All figures are medians unless stated, and every figure is a floor on true cost.
This article is a market-data benchmarking resource derived from publicly available CMS Open Payments and ClinicalTrials.gov data. Reported figures are disclosed industry research payments and represent a floor on trial cost, not a complete budget, a price quote, or financial advice. Trial budgeting decisions for any specific study remain the judgment of qualified professionals. Healthcare DealHub is not affiliated with CMS or the US government.