Introduction
Since the UK left the EU's centralized and mutual recognition frameworks, the Medicines and Healthcare products Regulatory Agency (MHRA) has had to build its own standalone route to market authorization for human medicines. The transitional reliance procedures that bridged the gap immediately after Brexit were always meant to be temporary, and on 1 January 2024 MHRA replaced them with something more durable: the International Recognition Procedure, or IRP. It's one of the more consequential regulatory policy changes for companies with UK ambitions in the past several years, and it's reshaping what regulatory affairs work in this market actually looks like.
For regulatory professionals, IRP is worth understanding in some depth, not just as a policy footnote. It changes submission sequencing strategy, creates new documentation requirements, and is opening up a specific kind of multi-jurisdiction regulatory work that didn't exist in this form before.
What the International Recognition Procedure Does
IRP lets MHRA draw on marketing authorization decisions already made by a defined list of trusted overseas regulators — MHRA refers to these as Reference Regulators — when assessing a UK application for the same product. Rather than repeating a full independent review from scratch, MHRA's assessment leans on the reference regulator's decision and supporting assessment, with UK-specific considerations layered on top. The Reference Regulator list includes agencies such as the US FDA, Health Canada, Switzerland's Swissmedic, Australia's TGA, and several individual EU member state national regulators, among others; the exact list is published by MHRA and reviewed periodically, so it's worth checking the current version rather than assuming it's static.
It's important to be precise about scope here: IRP applies to marketing authorizations for human medicines. It does not extend to medical devices, which continue to sit under a separate UK regulatory framework. Conflating the two in a job interview or a client conversation is a fast way to signal you haven't actually worked with either system closely.
How the Two Recognition Routes Work
IRP offers two main routes, and choosing between them is itself a piece of regulatory strategy. Recognition Route A is used when a company applies to MHRA around the same time as, or shortly after, submitting to a reference regulator, allowing the UK review to run in parallel with or close behind the reference assessment. Recognition Route B is used when a product already has a reference regulator's authorization in hand, letting the company bring that existing decision to MHRA as the basis for a UK application. Both routes carry published target assessment timelines that are meaningfully shorter than a standalone national UK assessment conducted without reliance on a reference decision, which is the core value proposition for sponsors weighing where to prioritize their submission effort.
Choosing the right route, and timing the UK filing relative to the reference jurisdiction's own review clock, is a genuine strategic decision rather than a formality. Get the sequencing wrong and a company can lose most of the time advantage IRP is supposed to offer.
There's also a pre-submission engagement option built into the procedure, allowing a company to approach MHRA before formally filing to discuss which route fits their situation and to flag any UK-specific issues early. Companies that skip this step and file cold sometimes discover UK-specific requirements — a labeling nuance, a risk management consideration, a question about how the reference regulator's data package maps onto UK expectations — later in the process than they'd like, at a point where addressing it costs more time than an early conversation would have.
Why This Matters for Regulatory Affairs Work
IRP has created a specific kind of regulatory strategy work: sequencing a global submission plan so that the UK filing lands at the right moment relative to FDA, EMA-adjacent national authorities, or whichever reference jurisdiction the product's approval strategy is built around. That's a materially different skill from simply knowing UK-specific dossier requirements. It requires someone who can hold multiple jurisdictions' timelines and requirements in view simultaneously and make a call about how the UK fits into the broader sequence.
There's also a layer of UK-specific nuance that doesn't disappear just because MHRA is relying on a reference decision. Labeling and packaging requirements, and the practical distinctions that still exist between Great Britain and Northern Ireland under the Windsor Framework arrangements, require dedicated attention regardless of which recognition route a company uses. IRP speeds up the assessment; it doesn't eliminate the need for UK-specific regulatory judgment.
The Skills Gap This Creates
Companies building out UK regulatory capability are increasingly looking for people who are fluent in more than one jurisdiction's requirements, not narrow UK specialists working in isolation. Understanding how MHRA's Reference Regulator list works, and staying current as it's updated, matters more than it might seem, since a company's optimal filing strategy can shift if a relevant reference jurisdiction is added or its status changes. Comfort with pre-submission engagement is also increasingly valuable, since IRP applications benefit from early dialogue with MHRA about route selection and timing in a way that a purely reactive regulatory affairs approach doesn't capture well.
What This Means for Job Seekers
Demand is building in a few specific places: companies with genuine UK commercial ambitions who need someone who can build a defensible multi-jurisdiction filing strategy, and consultancies and CROs that have built out dedicated UK regulatory strategy service lines to serve clients who don't want to build this expertise in-house. If you have IRP experience, or even close familiarity with how the recognition routes work in practice, it's worth naming specifically in interviews rather than folding it into a generic "UK regulatory experience" line — the specificity signals that you understand the mechanics, not just the headline.
Because the Reference Regulator list and the procedural details evolve, this is also a niche where staying current matters more than usual. Following MHRA's published guidance directly, rather than relying on secondhand summaries that may lag policy updates, is a reasonable habit to build if you're positioning yourself in this space.
How This Fits Alongside Other Post-Brexit Changes
IRP doesn't exist in isolation. It sits alongside other post-Brexit regulatory developments — the Windsor Framework's arrangements for Northern Ireland, MHRA's own evolving guidance on international collaboration, and the broader question of how UK requirements diverge from or track EU requirements over time. A regulatory professional who can speak to how IRP interacts with these adjacent pieces, rather than treating it as a standalone procedure, tends to come across as considerably more credible in both interviews and client conversations. It's also worth remembering that MHRA continues to run parallel routes for companies that don't have a reference regulator decision to draw on, so IRP is best understood as one tool among several in a company's UK regulatory strategy rather than the only path available.
What This Looks Like in Practice
Consider a mid-sized biotech planning a US filing for a new therapy, with a UK launch as a secondary but real priority. Under IRP, the regulatory team's job isn't simply to file a UK dossier once the FDA process concludes; it's to decide, early in the program, whether an IRP Route A filing timed alongside the FDA submission makes more sense than waiting for FDA approval and then using Route B. That decision depends on factors like how confident the team is in the FDA outcome, how much internal capacity exists to run two jurisdictions' processes in parallel, and how commercially urgent the UK launch actually is relative to other markets. None of that is a technical dossier question; it's a strategic judgment call that has to be made with incomplete information, which is exactly the kind of decision that separates a regulatory affairs professional who adds strategic value from one who only executes a plan someone else has already made.
The same reasoning applies in reverse for a company that's already established in the US or EU and treating the UK as an afterthought. Because Route B lets a company bring an existing reference regulator authorization to MHRA after the fact, there's a temptation to deprioritize UK filings entirely until a product is already approved and selling well elsewhere. That can work, but it also means the UK launch lags every other market by default, and a regulatory team that never builds the internal muscle for pre-submission engagement with MHRA may find itself unprepared the first time a program genuinely needs UK speed, whether because a competitor is moving quickly in that market or because of a specific commercial commitment made to a UK partner or payer.
Regulatory professionals who track this well tend to build a simple internal habit: reviewing, for each active program, whether the current UK plan reflects a deliberate choice or just a default assumption that's gone unexamined since the program's original filing strategy was set. That single question, asked periodically, catches more missed opportunities than any procedural checklist.
Conclusion
IRP is a genuine structural change in how the UK approves medicines, not a minor procedural tweak, and it rewards regulatory professionals who can think across jurisdictions rather than working UK requirements in isolation. For anyone building a regulatory affairs career with any UK exposure, understanding IRP's mechanics well enough to explain the tradeoff between Route A and Route B in a conversation is a small investment that's likely to keep paying off.