Opinion: If there’s no commercial incentive to develop gene therapy, hospitals will fill the gap

Cliare Booth
Cliare Booth

In The Conversation, Professor Claire Booth (UCL Great Ormond Street Institute of Child Health) explains why Great Ormond Street Hospital are developing gene therapy for a rare disease called ADA-SCID, a form of severe combined immune deficiency.

Individually, rare diseases are rare, but there are so many rare diseases that over  400 million people  are affected worldwide. Together, rare diseases aren’t so rare.

Only 5%  of rare diseases have an approved treatment so when we find a treatment that works, we must make sure that patients in need can access those treatments. At the moment, this doesn’t always happen.

For rare and ultra-rare diseases, it’s a sad fact that there is little commercial incentive for companies to develop costly treatments, like gene therapies, with very small markets. This means that treatments that have been shown to work in clinical trials, or even some licensed gene therapies, are not reaching patients.

Great Ormond Street Hospital (Gosh) will explore for the first time if an NHS hospital can plug this gap for UK patients. This is a new approach, and we may find out this isn’t the solution, but we cannot sit by while proven treatments stall - we must do something radical.

Gosh has been a leader in the field of gene therapy since it was first developed over 20 years ago. One type of gene therapy involves taking the patient’s blood stem cells and using a virus to insert a working copy of the faulty gene into the patient’s DNA.

This approach has been very successful in treating some inherited blood and immune system diseases. Together with colleagues at UCLA, our team at UCL Great Ormond Street Institute of Child Health developed a very effective gene therapy for a rare disease called  ADA-SCID  (a form of severe combined immune deficiency) in which the immune system doesn’t develop, leaving children extremely vulnerable to life-threatening infections.

Ninety-five per cent essentially cured

The results of clinical trials in UCLA and Gosh were published in the  New England Journal of Medicine  and showed all 50 patients survived, while over 95% were essentially cured and needed no further treatment.

The programme was initially supported by a pharmaceutical company, but, despite the remarkable results, it was not taken forward, leaving the entire community frustrated and disappointed.

Gene therapies like this are complex to make and are made for each patient individually, which contributes to a high cost that can reach over US$4 million (£3.1 million).

Ultimately, for a disease that affects fewer than ten patients a year in the UK and Europe, this is one of those markets where there is hardly any commercial reason for pharmaceutical companies to invest. ADA-SCID isn’t the only disease where this has happened, and it won’t be the last.

Gosh will explore whether it’s possible to apply for and take on the licenses for gene therapies like this one, making them accessible to children at Gosh and other hospitals in the UK through NHS agreements, using ADA-SCID as a pilot.

We hope to find a model that is both non-profit and sustainable, making the treatment widely available for years to come. Gosh is uniquely positioned to test this potential pathway as not only was the treatment developed and trialled here, but the hospital has its own licensed gene and cell manufacture facility on site, where the drugs could be made.

The San Raffaele Telethon Institute for Gene Therapy in Milan, Italy, recently found itself in a  similar situation  with promising gene therapies dropped by a commercial sponsor, including a drug ( Strimvelis ) licensed in Europe for the same disease.

The Telethon Foundation, a non-profit organisation, has committed to providing the therapy for eligible patients and is supporting another dropped gene therapy in their programme to move towards licensing.

We will probably see more academic institutions and specialised medical centres exploring these routes to get treatments for rare diseases to patients in need without industry involvement, but there will certainly be challenges, especially financial ones.

Gosh hopes that this project will create a framework for many other conditions, providing a tried and tested pathway to cures, and hope for many patients and families to come.

This article originally appeared in The Conversation on 12 June 2024.


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