Lumıary
Company reportedLive since 2025Added Oct 2026

Merck & Co. (MSD)

Merck uses generative AI to draft clinical study reports, cutting human-reviewed first drafts from 180 to 80 hours

Merck, the US drugmaker also known as MSD, built an internal generative AI platform with McKinsey that drafts clinical study reports for regulatory filings, with medical writers reviewing the output. Merck reports the human-reviewed first draft now takes an average of 80 hours, down from 180.

Move fasterImprove quality, reduce riskRaise productivity

Key figures

Copied exactly from the sources. Copy any figure with its citation.

From an average of 180 hours to 80 hours

Time to a fully human-reviewed first draft of a clinical study report, across multiple studies1

Reduced by 50%

Errors in drafts in categories such as data, citations and terminology1

From two to three weeks to three to four days

Time to create a first draft1

What it took

CostNot disclosed
TeamMore than 80 data science, AI, life science technology and medical experts across three continents1
TimelineNot disclosed

The problem

Before a medicine can be approved, a drugmaker must write long clinical study reports that describe what each trial found. Medical writers assemble them from tables, data and earlier documents. The work is slow, and mistakes in data, citations and terminology must be caught before submission.

What they built

Merck built an internal platform with McKinsey that uses large language models, the kind of AI that writes text, to produce first drafts of these reports. It pairs preparation of the results tables with AI-assisted drafting. Qualified medical writers review what it produces.

How they did it

A team of more than 80 specialists across three continents built and ran the platform. Merck trained staff in prompt engineering and data pipelines. The company submitted its first live reports made with the platform earlier in 2025 and planned to extend it across its late-phase pipeline by the end of that year.

Results

Merck reports that in use across several studies, the time to a fully human-reviewed first draft fell from an average of 180 hours to 80 hours. It says errors in categories such as data, citations and terminology fell by 50%. It also says first drafts that took two to three weeks now take three to four days.

Lessons for your project

  1. Measure to the finish line that matters. Merck counts time to a fully human-reviewed draft, not time to a raw machine draft.

  2. Keep qualified experts in the loop for regulated documents. Merck's medical writers oversee the output.

  3. Train staff to run the system. Merck taught its people prompt engineering and data pipeline skills.

  4. Combine domain experts, data scientists and technologists in one team rather than handing the build to IT alone.

Caveats

  • Both sources are Merck's own press release, in its merck.com and msd.com versions, so the figures are company-reported. No independent source confirms them.
  • The release does not name the model or any AI vendor; it says only large language models. McKinsey and its AI arm QuantumBlack are named as co-developers only in the msd.com version of the release; the merck.com version omits them.
  • The release gives no month for go-live; it says the first live reports were submitted earlier in 2025, so only the year is shown. The release date is 25 June 2025.
  • The release says Merck planned to scale the platform across its late-phase pipeline by the end of 2025. That plan is not a result.
  • A McKinsey blog post on the same work could not be read, so it is not cited.

Sources

Summarized in our own words from the sources above. Spotted an error? See corrections.

Related cases