Two children remain cancer-free for 18 months after gene-editing therapy

A new cancer treatment helped two children with leukaemia be disease-free for up to 18 months, new research reveals. One of the infants has shown no signs of the condition for 16 months, while the other has been in remission for a year-and-a-half, a new study found.

The youngsters received an immune-boosting treatment alongside a gene-editing technique, known as TALENS, that altered their Deoxy ribonucleic Acid (DNA)/genetic material.

Such DNA changes makes it easier to create immune cells that attach to, and destroy, tumours.

Yet, some experts argue it is unclear to what extent their remission is due to the new treatment and how much is the result of their previous chemotherapy and stem cell transplants.

TALENS is a form of gene editing that causes specific immune cells, known as T cells, to express proteins that target tumours.

Yet, some argue the technique CRISPR is more accurate to target cancer-causing genes. CRISPR works by cutting out a target area of DNA and replacing it with something else.

Cancer-causing genes can therefore be replaced with those that kill tumours.

Researchers from Great Ormond Street Hospital in London investigated a new cancer treatment in two infants with an aggressive form of leukaemia.

The youngsters had previously been treated with chemotherapy and received stem cell transplants.

The researchers made four DNA alterations on immune cells from donors and infused the cells into the patients.

Results revealed that both youngsters have been cancer-free for 16 and 18 months, respectively.

The findings were published in the journal Science Translational Medicine.

Meanwhile, hepatitis C can be completely cured with direct acting antivirals (DAAs) within thee months. However, as of 2015, only seven per cent of the 71 million people with chronic hepatitis C had access to treatment.

The World Health Organisation (WHO) is working to ensure that DAAs are affordable and accessible to those who need them. Prices have dropped dramatically in some countries (primarily in some high-burden, low-and lower middle income countries), facilitated by the introduction of generic versions of these medicines. The list of DAAs available to countries for treating hepatitis C is growing. WHO has just prequalified the first generic version of one of these drugs: sofosbuvir. The average price of the required three-month treatment course of this generic is between US$260 and US$280, a small fraction of the original cost of the medicine when it first went on the market in 2013. WHO prequalification guarantees a product’s quality, safety and efficacy and means it can now be procured by the United Nations and financing agencies such as UNITAID, which now includes medicines for people living with HIV who also have hepatitis C in the portfolio of conditions it covers.

How does the new cancer treatment work? The researchers combined a immune-boosting treatment with a gene-editing technique, known as TALENS.

Why is gene editing controversial? Gene-editing technology, such as CRISPR, can precisely ‘cut and paste’ sections of DNA to either remove unwanted genes or insert desirable ones.

Some have suggested the technology could be used to remove damaging genes from children before they are born, such as those that cause Huntington’s disease or hereditary blindness.

Yet the technology could also be used to insert genes for desired traits, such as blond hair or above-average height.

If science’s understanding of genetics improves, the technology may one day be used to insert genes that encode certain skills, such as musical ability.

For the immune-boosting therapy, specific immune cells are collected from patients’ blood and modified to contain certain receptors. They are then reintroduced into patients’ blood where the receptors attach to tumours, leading to their destruction. Although previous trials have demonstrated such treatments to be effective, modifying immune cells can be time consuming and expensive. Gene-editing, which allows patients’ DNA to be altered, makes it easier to create ‘universal’ immune cells.