The UK Kidney Association (UKKA) and the British Association for Paediatric Nephrology (BAPN) have submitted a joint response to the Medicines and Healthcare products Regulatory Agency (MHRA) consultation on its proposed Rare Disease Therapies Regulatory Framework, reflecting the views of the wider kidney community.

Around 1 in 17 people will be affected by a rare disease during their lifetime, affecting more than 3.5 million people across the UK. Yet only around 5% of rare diseases have an approved medicinal treatment, leaving thousands of conditions without satisfactory treatment options. Many kidney conditions fall within the rare disease definition, and advanced therapies have the potential to cure many of these conditions. However, without the right regulatory framework, there is little incentive to develop them.

The MHRA's proposed framework recognises that conventional drug development pathways are often not suitable for rare and ultra-rare diseases, where large patient populations and traditional Phase 3 clinical trials are frequently not feasible. 

It proposes the introduction of a new Investigational Marketing Authorisation (IMA) pathway, designed to provide greater regulatory flexibility and help innovative therapies reach patients sooner - while encouraging commercial interest alongside maximising academic engagement. 

In our response, the UKKA and BAPN welcome the MHRA's ambition to create a more flexible regulatory pathway for rare disease therapies. We believe the proposals represent a significant opportunity to support the translation of groundbreaking and often curative scientific advances into treatments for patients and to establish the UK as a world leader in rare disease therapy development. At the same time, we have identified several areas where further clarity will be essential if the framework is to achieve its full potential.

Our response calls for:

• a pragmatic and proportionate regulatory approach that maintains patient safety while improving access to innovative therapies
• ensuring the IMA pathway retains the flexibility to support investigator-initiated studies through to clinical trials
• allowing therapies to retain IMA status indefinitely where commercial investment is not forthcoming, so patients can continue receiving treatment
• proportionate manufacturing and regulatory requirements for therapies intended for very small patient populations
• earlier involvement of patients and families in study design and regulatory decision-making
• flexible approaches to evidence generation where conventional clinical trial designs are not feasible

Legislative changes and formal proposals are expected later in 2026. Through our policy work, clinical expertise and national research infrastructure, the UK Kidney Association will continue to support the development of innovative therapies for people living with rare kidney diseases and help shape the regulatory environment needed to bring them safely to patients.

Acknowledgements
The UK Kidney Association would like to thank Moin Saleem for leading the response, with valuable comments and contributions from John Sayer, Megan Griffith and Louise Oni.