What is the Rare Disease Therapies Regulatory Framework Proposed by the MHRA?

The Medicines and Healthcare products Regulatory Agency (MHRA) is the UK’s medicine regulator. It is the MHRA’s job to ensure that all medicines meet the agreed standards. Because of the unique challenges associated with developing medicines for rare diseases, the MHRA is overhauling how it evaluates them.

Last month, the MHRA launched a consultation, setting out its proposals for a brand new way to evaluate new medicines for rare diseases, called the ‘Rare Disease Therapies Regulatory Framework’. 

What are the Main Proposals of the MHRA's Rare Disease Regulatory Framework?

The MHRA’s proposed Framework introduces a flexible, modular system to regulate rare disease medicine development. It provides earlier regulatory engagement, ongoing, progressive approvals, and allows real-world evidence and prior scientific knowledge to be considered alongside traditional clinical trial data.

Why is the New Regulatory Framework Important for Rare Diseases Like PSC?

Overcomes Trial Barriers

Standard pathways require large, randomised controlled trials that can take decades to complete. For rare, variable conditions like PSC, recruiting enough participants for traditional long-term trials is exceptionally difficult.

Faster Access to Treatments

Unlike the rigid, multi-stage standard approval route, this framework uses flexible decision-making and early dialogue to significantly shorten the timeline from drug discovery to patient access.

Proportionate, Risk-Based Decisions

The MHRA can evaluate treatments based on high unmet medical need, enabling innovative, targeted therapies to reach patients sooner safely.

How Does the MHRA Define a ‘Rare’ Disease Under the Proposed Framework?

The Framework includes diseases with a prevalence (how many people have the disease) of only 1 in 50,000. Generally the UK and EU consider rare diseases to affect  1 in 2,000 people, so this new definition is much, much smaller, targeting only the ultra rare conditions.  

What is PSC Support’s Position on the Proposed MHRA Framework?

PSC Support has raised concerns regarding this threshold, noting that it risks excluding diseases like PSC which has a UK prevalence of approximately 5.6 to 10 in 100,000 people. PSC Support strongly supports the MHRA’s new Framework to speed up access to rare disease treatments, but we oppose excluding PSC based on an arbitrary prevalence cutoff. 

What Specific Changes is PSC Support Calling For in the MHRA Consultation?

PSC is a complex condition with a number of sub-groups (which individually would be within the rare definition), facing severe clinical trial barriers and a complete lack of approved medicines.  We have urged the MHRA to base eligibility into the Framework on high unmet need rather than exactly how ‘rare’ it is. Additionally, we have highlighted the need to:  

• Support drug repurposing: where generic medicines exist for other diseases that scientists think might help PSC patients, that regulation is streamlined, especially when the clinical trial is funded by charities and led by academic researchers, not pharmaceutical companies.  
• Use flexible evidence: Accept patient-reported outcome measures and digital health technologies, such as wearables, to measure real-world symptoms like fatigue and itch.
• Recognise patient risk tolerance: Assess patients' individual appetite for risk, acknowledging that people facing progressive diseases like PSC may accept higher risks for potential treatments.  
• Embed patient involvement: Involve patient organisations throughout the regulatory process to improve study design and ensure patient priorities are heard. 

 

We will keep you updated on the progress of this MHRA consultation and our ongoing work to accelerate access to safe, effective treatments.