Gene therapy is no longer confined to science-fiction stories. Across Europe, approved treatments are already helping some patients by addressing the genetic causes of disease, although high development costs and limited access remain significant obstacles.
The technology recently gained popular attention through its fictional use in Spider-Man: Brand New Day, where RNA interference is used to silence gene activity. In real medicine, gene therapy is more carefully targeted: it introduces, alters or suppresses genetic material in cells to treat illness.
What is gene therapy?
Gene therapy is a medical approach designed to treat disease by targeting genetic mechanisms. It may be used for inherited conditions caused by a faulty gene, but researchers are also studying applications in cancer, HIV and other serious illnesses.
According to Alberto Auricchio, director of the Telethon Institute of Genetics and Medicine in Naples, the treatment involves introducing nucleic acids, such as DNA or RNA, into specific cells or tissues for therapeutic purposes.
There are two main delivery approaches:
- In vivo treatment: genetic material is delivered directly inside the patient’s body.
- Ex vivo treatment: cells are removed from the patient, modified in a laboratory and then returned to the body.
Scientists use viral or non-viral vectors to deliver the genetic material. Viral vectors are modified so they can carry therapeutic instructions without causing the original infection, while non-viral methods use alternative delivery systems.
Gene addition, correction and silencing
Gene therapy includes several different techniques. Gene addition supplies cells with a working copy of a gene. Gene correction attempts to repair a faulty genetic sequence, while gene silencing switches down or deactivates unwanted gene activity.
RNA interference, the fictional treatment referenced in the film, is a real technique associated with gene silencing. It can prevent particular genetic instructions from being translated into proteins. However, real treatments require rigorous development, clinical testing and regulatory review; they do not produce the dramatic or unpredictable transformations shown in superhero films.
Gene therapy in Europe has already reached patients
European gene therapy is no longer limited to experimental research. The source material identifies Glybera as the first in vivo gene therapy to receive European Commission marketing authorisation, in 2012. It was intended for patients with severe or repeated pancreatitis attacks linked to lipoprotein lipase deficiency.
Strimvelis became the first ex vivo gene therapy authorised in Europe in 2016. Developed at the Hospital San Raffaele in Milan, it treats severe combined immunodeficiency caused by adenosine deaminase deficiency.
These examples illustrate the difference between a research concept and an authorised medicinal product. Approval means a treatment has passed the relevant regulatory process for its indicated use; it does not mean gene therapy is suitable for every genetic condition or widely available to all patients.
Why gene therapy is considered promising
The central attraction of gene therapy is durability. Unlike medicines that must be taken daily or repeatedly, some gene therapies are designed as one-time treatments. Their aim is to create a lasting therapeutic effect by changing the underlying biological process responsible for the disease.
Long-term follow-up has shown that some approved treatments can maintain their effect for many years. In certain cases, the intended benefit may last for the patient’s lifetime, although outcomes depend on the disease, the treatment technology and the individual response.
Potential advantages include:
- Addressing the biological cause of an inherited disease rather than only managing symptoms.
- Reducing the need for repeated treatment in some conditions.
- Opening new options for rare diseases with few existing therapies.
- Supporting research into complex conditions such as cancer and HIV.
The cost and access problem
The biggest barrier is not only scientific complexity. Gene therapies can require substantial research, specialised manufacturing and highly controlled clinical care. Because many are developed for rare diseases, manufacturers may face a small potential patient population while carrying significant development costs.
Those pressures can result in prices running into hundreds of thousands or millions of euros. The source article gives Strimvelis as an example, with a reported cost of €594,000 excluding VAT.
That creates difficult questions for European health systems:
- How should one-time treatments be funded?
- How can hospitals develop the expertise needed to administer them?
- What evidence is sufficient when patient populations are small?
- How should public authorities assess long-term value and affordability?
These questions affect national health services and insurers as well as patients. Marketing authorisation at European level does not automatically guarantee equal access in every country, because reimbursement and healthcare delivery involve national systems.
What happens next for gene therapy?
Research is continuing to improve delivery methods, make treatments more precise and expand the range of diseases that can be addressed. Scientists must also monitor safety, durability and possible immune reactions over the long term.
For patients and families, the most important distinction is between a promising laboratory technique, a clinical trial and an approved therapy. Each stage involves different evidence and different levels of access.
Conclusion
Gene therapy has moved from science fiction into real European healthcare, with authorised treatments demonstrating that genetic diseases can sometimes be treated at their source. The next challenge is making these therapies safer, more scalable and financially accessible, so that scientific breakthroughs do not remain available only to a small number of patients.
