Gene therapy concept render

Gene therapy is an innovative technique that modifies genes to treat or prevent diseases, offering hope for genetic and acquired conditions.

About this subject

Gene therapy represents a revolution in modern medicine. Unlike traditional treatments that alleviate symptoms, it attacks the root cause by correcting defective genes or introducing functional ones. The first clinical success occurred in 1990 when a girl with severe combined immunodeficiency (SCID) received modified cells. Since then, the technique has evolved from viral vectors like retroviruses and adenoviruses to new approaches such as CRISPR-Cas9, a gene-editing tool that allows precise cuts in DNA.

In Brazil, gene therapy is still emerging, but initiatives exist. In 2023, the Unified Health System (SUS) incorporated treatment for spinal muscular atrophy (SMA) using Zolgensma, which replaces the defective SMN1 gene. This milestone costs around R$6.8 million per patient, but SUS negotiates lower prices. Globally, over 2,000 gene therapy clinical trials are ongoing as of 2024, focusing on cancer (CAR-T cell), hereditary diseases like hemophilia and cystic fibrosis, and even acquired conditions such as Parkinson's.

Despite advances, challenges remain. Viral vectors can trigger immune reactions, and precise delivery of genetic corrections to specific organs is still limited. Furthermore, high costs and ethical issues, such as editing germline cells (affecting future generations), spark debates. The scientific community remains cautious, but results in patients with previously fatal diseases highlight the transformative potential of this therapy.

Frequently Asked Questions

What diseases can be treated with gene therapy currently?

Gene therapy is approved for diseases like spinal muscular atrophy (SMA), immunodeficiencies, hemophilia B, and some cancers (e.g., leukemia with CAR-T cells). Clinical trials test its use in cystic fibrosis, Duchenne muscular dystrophy, and neurodegenerative diseases.

What is the difference between gene therapy and gene editing?

Gene therapy typically introduces a functional gene using viral vectors, while gene editing (e.g., CRISPR) directly alters the existing DNA at the correct location. Editing allows more precise corrections but still faces safety challenges.

Is gene therapy safe?

Although there are risks like immune reactions or incorrect gene insertion, safety has improved with more specific vectors and rigorous protocols. Regulatory agencies such as FDA and ANVISA require extensive clinical trials before approval.