Gene Therapies 101
We want to answer some of the most common questions patients and payers have about these life-saving treatments.
What are gene therapies?
Gene therapies are highly-targeted medications that introduce genetic material into a person’s DNA to “edit” and replace faulty or missing genetic material that leads to disease. Unlike nearly all other medications that are repeatedly taken over time, the two currently approved gene therapies are intended to be administered once with the expectation to provide long-term benefit, and in some cases, a cure. While practical applications of gene therapies weren’t approved for use in the U.S. until 2017, the concept of them has been around since the early 1970s.
These therapies are administered in varying ways, usually requiring extensive training, specific handling procedures and equipment entrusted only to certified sites of care and medical professionals.
Note that CRISPR, which has received a lot of attention, is not a gene therapy. Instead, it’s one of several genetic editing tools that are part of the larger science that goes into gene therapy treatments.
Are gene therapies safe?
Like all treatments, there are some health risks related to gene therapies. However, like other treatments, before gene therapies hit the market, they go through rigorous testing and all appropriate regulatory agencies like the Food and Drug Administration (FDA) that regulates and approves gene therapy products and the National Institutes of Health (NIH) that ethical standards for investigators and institutions.
What can gene therapies treat?
To date, two gene replacement therapies have been approved in the U.S. – Luxturna® and Zolgensma®. Luxturna, launched by Spark Therapeutics, is for the treatment of a rare condition causing blindness; and Zolgensma, from Novartis, for the treatment of Spinal Muscular Atrophy (SMA) in infants. Although both of these therapies are intended for rare conditions, many of the gene therapies in the near-term pipeline are for more prevalent conditions like cancer and hemophilia. In fact, the FDA expects to approve 10-20 gene and cell therapies per year by 2025.
How do we know these therapies are effective?
Dramatic vision improvements have been seen almost immediately with patients receiving Luxturna. Patients have been able to do simple things not otherwise possible, like walking without assistance, playing sports, even driving cars with the help of this therapy.
SMA is the leading genetic cause of infant mortality – untreated, life expectancy for an infant with type 1 SMA is only two years. Post-approval data, for the oldest living patients treated with Zolgensma®, demonstrate survival rates thus far to 5 years of age, while achieving historically impossible motor milestones, including the ability to walk independently.
Clinical trials for hemophilia gene replacement products are showing incredible promise, with one study showing over a 95% decrease in both bleed rate and amount of factor used.
Will gene therapies become commonplace in the future?
Approximately 4,000 rare diseases are linked to genetic disorders that currently do not have an effective treatment. Gene therapy has the potential to treat – and cure – some of the most debilitating diseases patients face.
With 600+ gene and cell therapies in the pipeline for varying conditions, we can expect gene therapy treatments will continue to be introduced and be representative of both ultra-rare and more prevalent conditions.