Tylenol-based gene therapy makes treating genetic diseases a ‘walk in the park’

PORTLAND, Ore. — Tylenol is a common pain reliever all over the world, but a new study finds another use for this over-the-counter medication you won’t find on the back of the bottle. Researchers at the Oregon Health & Science University School of Medicine have created a brand new method which uses the drug to stop genetic diseases.

Tylenol, also called acetaminophen, typically treats symptoms of pain and fevers in patients. In the new study, researchers used it in a gene therapy which treats the blood-clotting disorder hemophilia as well as the metabolic disease phenylketonuria (PKU) in mice.

Specifically, the team used a harmless lentivirus to correct genetic mutations which lead to disease. This process also inserts a new gene into the patient which makes liver cells immune to the toxic effects of exposure to Tylenol. This second step is key because it allows treated cells to survive and kills off untreated cells after repeated exposure to the drug. The result makes it possible for treated cells to multiply, ridding the liver of more mutations.

“This gene therapy gets rid of liver cells that don’t have a therapeutic gene inserted,” explains corresponding author, Markus Grompe, M.D., an OHSU professor of pediatrics, and molecular and medical genetics in a university release.

“We’re essentially poisoning untreated cells with excess amounts of Tylenol, an accessible drug that is already used by millions of people across the globe. Plus, acetaminophen’s potential toxicity is controllable and doesn’t leave permanent harm. Taking Tylenol to correct a genetic disease is a relative walk in the park, compared to the intense chemotherapy and radiation treatments patients have to undergo before they can receive a bone marrow transplant, for example.”

Can Tylenol end the need for liver transplants?

Typically, gene therapies like Luxturna – which treats an inherited genetic disease that causes blindness – use adenoviruses (AAV) to deliver gene-repairing molecules to a patient’s DNA. Study authors say AAV works well in cells that don’t replicate, like in the brain and eyes. However, these treatments have much less success reversing mutations in cells which do multiply, like the liver.

These gene therapies suffer from cell division because as cells continue to multiply, it dilutes the impact of repairing one cell at a time. Simply put, normal gene therapies can’t keep up. The problem is even worse in children, whose cells multiply much faster than an adult’s.

Gene therapies which use a lentivirus, on the other hand, appear to be more durable when it comes to making genetic changes in patients. This method allows for the genetic corrections it delivers to be passed on when cells multiply.

Also, standard gene therapies can’t fix all the cells suffering from mutations. This means doctors have to give patients large doses of their treatments to make sure enough cells get the genetic changes they need. When scientists insert Tylenol resistance into cells, the new gene therapy is effective using just one-tenth of the dosage size current AAV treatments use. Moreover, researchers say Tylenol resistance is something they can add to several other kinds of gene therapies, including AAV.

Grompe’s team believes this new gene therapy can cut down on the need for expensive liver transplants in patients with severe disease. It may also help reverse more genetic mutations in children and cut the cost of these therapies dramatically.

The study appears in the journal Science Translational Medicine.

Leave a Reply

Your email address will not be published.