Gene-silencing technologyat 29.12.2021
In August 2018, the prestigious journal "Nature" published an intriguing article about a new genetic technology that has been in use for more than two decades. This technique is the so-called RNA interference therapy, which can "silence" the activity of specific genes linked to various diseases. This year, the European Union and the United Kingdom approved and launched such an injection to reduce the risk of heart attacks and strokes.
American scientists Andrew Z. Fire and Craig C. Mello, who received the Nobel Prize in Physiology in 2006, discovered in the 1990sthe ability of RNA interference to silence genes.
How does this technology function? Our DNA contains the "plan" for making proteins, but it cannot send instructions directly to the cytoplasm because it is in the nucleus. For the communication between DNA and proteins, our body employs a short strand of genetic code known as RNA messenger, which transmits DNA instructions to protein "factories." When the DNA is altered, it sends erroneous instructions to the proteins, resulting in the onset or worsening of the disease. The "RNA interference" procedure entails interfering with the natural messenger RNA to "order" the production of toxic proteins. The natural messenger RNA is destroyed and replaced by an artificial messenger RNA, which sends a different message, resulting in the production of healthy proteins.
Patisiranum, marketed as "Onpattro," is the first RNA interference-based drug and was approved in 2018 . It was used to treat polyneuropathy in people with hereditary amyloidosis mediated by transthyretin. This rare condition can affect heart function and nerve function. Hereditary transthyretin-mediated amyloidosis is a fatal disease that affects an estimated 50,000 people worldwide. It is the first FDA-approved low-dose RNA interfering drug and the first FDA-approved drug to treat this condition. It's a gene-silencing medication that prevents the production of an abnormal form of transthyretin. In addition, Patisiranum employs a novel method of reducing TTR protein production in the liver via interfering RNA.
"This approval is critical to the field of RNA interference," said James Cardia, head of business development at Marlborough, Massachusetts-based RXi Pharmaceuticals, which is developing such RNA interference treatments. "This event will change pharmacology," Cardia predicted. Indeed, the drug's approval will force the rewriting of pharmacology textbooks, according to Ricardo Titze-de-Almeida, an RNA interference researcher at the University of Brasilia.
This year, the European Union approved another drug based on RNA interference technology in December 2020, with the National Health Service of the United Kingdom promising approval in early September 2021. The new drug is Inclisiran, marketed as "Leqvio," useful for people with high cholesterol who have previously had a heart attack or stroke to lower their cholesterol and prevent future events of this type. According to the UK National Health Service, Inclisiran could prevent 55,000 heart attacks and strokes, potentially saving 30,000 lives in England over the next ten years .
Inclisiran is one of the first drugs in a completely new class that uses the RNA interference procedure - a category known as gene silencing drugs - to block the production of molecules specific to the disease. Inclisiran works by increasing the liver's ability to remove harmful cholesterol from the blood. Inclisiran injections given twice a year may lower LDL cholesterol in patients with heart disease whose cholesterol levels are uncontrollable with statins or other medications.
"Inclisiran is very appealing because it only needs to be given twice a year via a simple subcutaneous injection," said Professor Nilesh Jayantilal Samani, a British physician and Professor of Cardiology at Leicester University as well as a consultant cardiologist at Glenfield Hospital. "More research is needed to confirm the extent of its benefits, but I expect it to be widely used to lower cholesterol for a much larger group of people in the future."