Gene editing, a cutting-edge genetic engineering technique, can alter precise target genes within an organism's genome with notable accuracy.

Since its inception in 2012, the gene editing marvel CRISPR is revolutionizing medicine. Dubbed the " genetic scissors," this technology holds promise for treating a spectrum of ailments, from rare genetic disorders to cancer, hypercholesterolemia, infertility, and more, reshaping the lives of countless patients.

In 2020, Scientists Emmanuelle Charpentier and Jennifer Doudna clinched the Nobel Prize in Chemistry for their groundbreaking work on related technologies. This innovation has evolved into a powerful tool for accurately and efficiently modifying cell genes in a programmed manner.

On December 8, 2023, the U.S. Food and Drug Administration (FDA) gave the green light for the marketing of the CRISPR/Cas9 gene editing therapy Casgevy (also known as exa-cel, with the generic name exagamglogene autotemcel) to treat sickle cell disease (SCD). This marks the second global approval for a gene editing therapy. Before this, on November 16, the UK Medicines and Healthcare products Regulatory Agency (MHRA) made public on its official website that it had granted approval for the CRISPR gene editing therapy Casgevy for patients aged 12 and above with sickle cell disease and those with transfusion-dependent β-thalassemia.

Sickle cell disease stems from a genetic mutation triggering abnormal hemoglobin production, leading to the clustering of red blood cells, which alters their usual flexible round structure into rigid crescent shapes resembling sickles. These misshapen cells have the potential to obstruct blood vessels, resulting in vascular blockages, harming blood vessel linings, and inducing potentially fatal blood clots.

Per a statement from the UK Medicines and Healthcare products Regulatory Agency, clinical trial findings revealed that 97% of sickle cell disease patients didn't report severe pain for at least 12 months post-administration of this gene editing therapy. Additionally, 93% of individuals with transfusion-dependent β-thalassemia didn't require red blood cell transfusions for a minimum of 12 months following the therapy.

Before this breakthrough, bone marrow transplantation stood as the sole long-term treatment for patients grappling with both conditions. However, finding a matching donor for the transplanted bone marrow was imperative, with the looming risk of rejection adding further complexity.

In the realm of medical advancements, gene editing technology finds its most prominent application in cancer treatment. Globally, there are numerous ongoing or completed clinical trials utilizing CRISPR gene editing, with a significant portion dedicated to cancer treatment. Approximately half of all gene therapy clinical trials are focused on addressing various aspects of cancer.

Chimeric antigen receptor T cell immunotherapy (CAR-T) stands as a cancer treatment approach leveraging genetic modification to convert T cells into specialized killer cells that pinpoint particular tumors. Its efficacy shines in combating blood cancers like leukemia, lymphoma, and myeloma.

In conventional CAR-T therapy, the patient's T cells are extracted, genetically modified outside the body, multiplied to reach the necessary treatment quantity, and subsequently reintroduced into the patient. This procedure is time-consuming and could potentially overlook treatment windows. Furthermore, frail children and elderly individuals might not yield sufficient T cells for extraction.

With the utilization of CRISPR technology to deactivate specific recognition genes within T cells, it becomes feasible to establish a universally applicable CAR-T cell reservoir, thereby reducing treatment duration and broadening the scope of eligible patients.

While gene therapy advancements leveraging CRISPR gene editing technology have reached remarkable heights, the FDA's approval marks a significant milestone. Nonetheless, the pressing challenge ahead lies in devising gene editing therapies that are both standardized, scalable, safe, and accessible at reasonable prices, ensuring affordability for all.

The approval of Casgevy therapy signifies not the culmination, but the much-anticipated commencement of a journey.