Progress in treating rare conditions: hype and hope?

How many lives have you saved today? 

“Don’t just say you want to help people!” my grandfather urged when I was preparing medical school applications. I was taken aback… but his intention was to widen my outlook, to consider qualities of a good doctor: scientific understanding, practical know-how, empathy. Not having been to university himself, he encouraged me to apply to Cambridge and later for medicine in London.  

Every phone call then began with; “How many lives have you saved today?”  

This worked better when I was on the paediatric ward - I’ll never forget the little girl with meningococcal septicaemia whose life we saved with antibiotics. But this dried up when I started training in clinical genetics… An obvious unsaid question hung between us, why had I chosen to work with rare conditions, where there were so few diagnoses and treatments? 

As I prepare to see a family with a new diagnosis, the question at the top of my mind is: Are there effective treatments?  

Every healthcare professional wants to offer a cure, and patients and families want to hear they will get better or stay well. When the answer is so often ‘not yet’, one can despair of hope.  

Knowledge is power, useful for planning life and unlocking resources; anticipating problems that can be fixed or made better; finding a supportive community that understands what you’re going through.  

But still, why does it take so long to develop treatments? 

Do the best you can until you know better. Then when you know better, do better 

This quote, often attributed to Maya Angelou, captures the sea change in our understanding of what causes genetic conditions, enabling us to target them upstream, at source, so we can do better.  

Phenomenal progress in science means new treatment strategies are now possible, targeting DNA and RNA - the building blocks of life - that we couldn’t have dreamt for before. 

The first genomics of rare diseases conference I went to had a session about therapies. A researcher shared findings from a study in mice that showed how mums could pass on a treatment to their pups early in life via their milk. The earlier the treatment was started, the better the outcomes.  

It was daunting to think of the work that had gone into this. Masses of research to untangle the underlying biology, identifying a druggable target and a potential drug, and then experiments to calculate dosage, success, side effects etc.  

And all of this before any human trials, which would raise its own challenges, from recruiting sufficient patients, spread across the country and globe, diagnosing early enough to make a difference, lack of funding, as well as systems from hospitals to governments. 

Paradigm shift 

There is sometimes a perception that moving towards personalised treatments narrows down our focus, makes treatments more expensive and less available. But what if they open the door to making a treatment for everyone that needs one?  

There are at least 300 million people in the world with a rare condition - even more than those living with cancer. By opening up new strategies for genomic-based treatments, it could be possible to target many more conditions from common through to ultra-rare. 

‘Nature’s 10’ on people who shaped science in 2025 features 2 amazing firsts that illustrate the potential:  

First, a gene therapy for Huntington's that slowed the rate of decline in movement and cognitive functions by an unprecedented 75% in the pioneer 12 patients. The treatment, administered via brain surgery, works by switching off production of the faulty protein that destroys brain cells. The trial’s lead scientific adviser said, ‘the dial has been shifted’. 

Second, the first personalised CRISPR therapy for baby KJ Muldoon, who has a rare metabolic disorder, edited his liver cells to correct the genetic change causing the condition, and was made just for him in a lightning 6 months to save his life.  

Collectively, rare conditions have a huge public health impact, and if we can learn to do this at scale, the benefits would be massive. 

Now and in the future 

For the small but growing number of rare conditions where life-changing treatment is available now, the NHS is working towards earlier diagnosis to maximise the chances of better outcomes.  

The Generation Study, a research project embedded within the NHS, is helping diagnose children earlier, by offering newborn genome sequencing. As part of this study, babies have already received treatments for eye tumours and for SMA - a severe muscle condition, both before symptoms had even started. 

Resources such as the National Genomic Research Library, run by Genomics England in partnership with the NHS, can enable finding patients at scale, based on their genetic variants, across numerous rare conditions, under different clinical teams and hospitals, so no one is left behind. 

There are also several collaborative initiatives in the UK that are moving us closer towards more personalised treatment for those with rare conditions: 

The Rare Therapies Launchpad consortium has helped create the environment for treating the first patient in the UK with an individualised therapy known as an antisense oligononucleotide (ASO) at Great Ormond Street Hospital in January 2026. Children with different conditions, and treated with different individualised medicines, will be part of the same study, so the learnings from every individual can be shared for all. 

The UK platform for nucleic acid therapies (DNA or RNA-based treatments), are designing a UK framework for the equitable selection of new drug targets. This builds on pioneering work from the N=1 collaborative, a global initiative to create a set of guidelines for genomic treatments, available to all.  

The UK Rare Diseases Framework, led by the Department of Health and Social Care, also helps drive collaborative progress across the ecosystem and includes an action to support equitable delivery of individualised therapies within the NHS. 

Happily, I believe we are going through a transformational change, and the rare community is helping to achieve the impossible. Crucially, this shift is happening across society: scientific, cultural, and policy.  

A final note 

Hype or Hope? I figure both co-exist. We are at the beginning of the journey for many experimental therapies, and caution is the only safe answer. I also believe therapies targeting our DNA and RNA provide hope. I can only try to imagine what will be achieved in our lifetime – more than I dreamt of a decade ago.  

We have a moral and ethical duty to help everyone, no matter how rare or common their condition. With novel and smart treatment strategies that break down barriers between rare and common and target conditions at their source, we can do good in the world and help people…  

How many lives have you saved today? Maybe sooner than I thought, the answer will be many lives have been saved, too many to count!