Core-Claims Libraries: The MLR Best Practice Nobody Wants to Maintain

Ask an MLR veteran for the single best way to make review faster, and you will usually hear the same three words: core-claims library. Ask who is actually funding and maintaining one, and the room goes quiet. As one veteran put it, everyone supports core claims right up until it is time to fund, develop, and maintain them.

That gap, between universal endorsement and chronic neglect, is one of the more expensive open secrets in pharmaceutical content. Here is what a core-claims library is, why it is the highest-leverage fix for slow MLR review, why it so often rots, and what a good one looks like.

What a core-claims library actually is

A core-claims library is a curated, pre-approved set of claims, each one locked to the reference (or references) that substantiate it and to the relevant label. Instead of writing a claim from scratch and sending it into review to be substantiated for the hundredth time, a writer assembles a piece from blocks that have already cleared MLR.

The payoff is structural. A claim that has already been approved, with its evidence attached, does not need to be re-argued every time it appears. The same sentence, worded the same way and referenced the same way, can flow into an email, a sales aid, and a congress panel without three separate substantiation debates.

Why it is the highest-leverage MLR fix

We have written about why promotional materials get sent back ten or more times. A large share of those rounds are the same claims being re-litigated, project after project. A core-claims library attacks that at the root:

It kills repeat work. Approved language is reused, not rebuilt.
It enforces consistency. One claim, one wording, one reference set, everywhere, which is the cleanest defense against the claim drift that turns an approved line into a non-compliant one.
It speeds launches. When demand spikes, teams assemble from approved blocks instead of starting cold.

This is why practitioners endorse it almost universally. It is also why its absence is so costly.

So why doesn't everyone have a great one?

Because building a library is a project, and maintaining it is forever.

A core-claims library is never "done." Every new publication, every label update, every rejected claim changes what belongs in it. Keep it current and it is the most valuable asset the commercial team has. Let it drift for two quarters and people stop trusting it, which means they stop using it, which means you are back to writing claims from scratch.

And maintenance is precisely the part nobody wants to own. The data tells the story: when MLR workload spikes, most teams simply absorb it with existing staff, and only about 5% invest in the technology or process that would actually scale the work. The library is everyone's best practice and no one's job.

Turnover makes it worse. The person who knew the library, who remembered why a particular phrasing was chosen and which one had been rejected, leaves, and the institutional memory leaves with them.

The access and memory gaps that quietly defeat it

Even where a library exists, two gaps undermine it:

It is not the single source of truth. Approved claims are not always formalized in the system; plenty live in old decks and people's heads. And external agencies frequently cannot see the full library at all, so they recreate claims that already exist, or worse, re-submit ones that were already rejected.
It remembers approvals but forgets rejections. Most libraries track what was approved. The good ones also track what was rejected and why, so the same non-compliant claim does not keep resurfacing every cycle. A record of what you cannot say, and the reason, is as valuable as the list of what you can.

What a good one looks like

A core-claims library worth maintaining is:

Locked to evidence. Every claim tied to its approved reference and the correct region's label, not just a free-floating sentence.
Owned and versioned. Someone maintains it, and it updates when a label or a key study changes.
Open to everyone who writes, including the agencies and freelancers actually producing the content.
Honest about rejections, carrying the history of what failed and why.

Platforms like Veeva Vault PromoMats offer dedicated Claims Management tooling, and Veeva clearly knows that upkeep is the hard part. Alongside a central library and automated claim linking, it is rolling out capabilities aimed squarely at maintenance: claims harvested into the library on approval, and an AI "Claims Agent" for substantiation and library upkeep slated for August 2026. Those newest pieces are recent enough that the field has not had time to judge how much they ease the burden in practice, so we are watching with interest rather than calling the problem solved. The encouraging part is that the tooling is finally pointed at the right problem.

The point is not to have a library. It is to use it automatically.

A library only works if people actually check it at the moment they write, and that is exactly where good intentions break down. The fix is to make the check automatic rather than optional.

This is the thinking behind PharmaText.ai. Instead of trusting a writer to remember to open the claims document, our Precision Traceability engine keeps every claim tied to its approved source as the content is drafted, and flags the moment a claim drifts from, or contradicts, the evidence behind it. The approved-claim discipline stops being a document people forget and becomes part of the writing itself, which is the only version of a core-claims library that survives contact with a deadline.

Sources: MLR workload and technology-investment figures from a 2024 industry webinar by Impatient Health.