Clinical trial cost per patient: why phase 1 costs 5x phase 3

A reasonable person might assume that trial costs climb with each phase. Per trial, they barely move, but per patient, they collapse.

Across 4,015 US trials with disclosed industry research payments, the median phase 1 trial is $455K in disclosed funding and the median phase 3 trial is $463K. Effectively the same floor of dollars. But a median phase 1 trial enrolls 42 people and a phase 2 enrolls 84, while phase 3 cohorts reach into the hundreds. Divide spend by enrollment and the picture inverts: $10.6K per enrollee at phase 1, $4.0K at phase 2, $2.1K at phase 3.

Phase 1 costs five times more per patient because everything about it is small and intensive. A first-in-human study pays for dense monitoring, frequent visits and per-patient attention that a 900-person outcomes trial never could. Phase 3 looks cheap per patient because scale absorbs the same dollars. Neither number is wrong. They are answers to different questions, and budgeting from the wrong one is how trials get mispriced.

The benchmarks, by phase

Median disclosed cost per enrollee, with the middle half of trials around it:

Phase 1: $10.6K, middle half $2.2K to $31.7K (937 trials). Phase 1/2: $5.6K, middle half $1.6K to $20.2K (306). Phase 2: $4.0K, middle half $831 to $14.7K (1,098). Phase 3: $2.1K, middle half $272 to $6.9K (1,375). Phase 4: $2.7K, middle half $560 to $9.1K (299).

Phase 4 breaking the downward pattern is interesting. Post-approval studies are smaller than pivotal trials, so their per-patient figure climbs back above phase 3 even though their per-trial floor is the lowest of any phase at $149K.

The spread inside a phase beats the gap between phases

Phase 3 stretches from $272 per enrollee at the 25th percentile to $15.7K at the 90th. That spread is wider than the entire distance between the phase median and two phase 3 trials can sit a factor of 50 apart.

Part of the low end is reporting, not economics. Some trials match to only a handful of disclosed payments, which drags the bottom percentiles toward zero, which indicates that you should benchmark from the median up, and treat anything below the 25th percentile as a floor of the floor.

Phase + area = a usable range

Therapeutic area impacts the number almost as much as phase does. At phase 1, cardiometabolic trials top the grid at $17.9K per enrollee and respiratory sits at $5.6K. At phase 3, infectious disease is the floor at $656, a legacy of enormous vaccine cohorts, while rare disease holds $3.7K.

Oncology is the odd one. It sits below the cross-area median at every phase, $7.7K at phase 1 against a $10.6K norm, despite cancer holding more trial money than any other area. Learn more here: oncology trial cost.

How to use these numbers

Pick the phase, pick the area, and read the median and 25th / 75th split. That is a defensible starting range for what US physician and site payments should look like per patient, built from disclosed data you can cite, before a vendor quote frames the conversation for you.

Then remember what the number is. Disclosed payments are a floor on trial cost, not a budget. Full per-patient costs for pivotal trials have been estimated near $41K, many multiples of the phase 3 floor here, because much of a trial's budget flows through channels sponsors do not disclose at the trial level. What the floor gives you is the piece nobody can argue with. The method and its blind spots: where the data comes from. The metric itself: cost per enrollee. The full picture across all 5,413 trials: what a clinical trial costs.

Common questions

What does a phase 1 trial cost per patient? Median disclosed spend is $10.6k per enrollee, with the middle half of phase 1 trials between $2.2K and $31.7K. Small cohorts and intensive per-patient work keep it the most expensive phase per enrollee.

Why are phase 3 trials cheaper per patient? Because enrollment grows faster than spending. The median phase 3 trial shows roughly the same disclosed total as a phase 1 trial but spreads it across hundreds of patients instead of 42, landing at $2,148 per enrollee.

What does a pivotal trial cost per patient? Published estimates of full pivotal-trial costs put the median near $41.1k per patient. The disclosed floor for phase 3 is $2.1K, and the distance between those numbers is the spending that never reaches public data: CRO fees, non-US sites and everything outside the US disclosure rules.

Data notes

Figures come from CMS Open Payments research payment records matched to ClinicalTrials.gov by NCT number 2020–2024 (January 2026 file release). Phase benchmarks cover the 4,015 matched US trials that carry a drug-development phase; registries and no-phase device studies are excluded. All figures are medians or stated percentiles, never means. Cost per enrollee is disclosed payments divided by reported enrollment. Low percentiles reflect trials with few matched payments and should be read as reporting artifacts, not market prices. 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.