Progeria is a rare genetic disease that results in premature aging. Children with progeria will appear old and frail even before they reach school age, and they’re likely to die in their early teens from heart disease or a stroke.
Up to now, there has been no treatment. But the U.S. Food and Drug Administration recently approved the first drug for this devastating disease.
There are different forms of progeria, but the classic type is called Hutchinson-Gilford Progeria Syndrome, named after the two English physicians who described it in the late 1800s. Progeria occurs in about 1 in 20 million births worldwide. Progeria is caused by a mutation in the LMNA gene, which codes for two proteins called lamin-A and lamin-C.
These proteins form a sort of scaffolding for the nucleus of cells, which houses genetic information. They form a mesh-like structure, the nuclear lamina, which holds up the membrane that encloses the nucleus. Humans need only one copy of the mutated gene on chromosome 1 to have progeria, making it a dominant genetic disorder.
Progeria is the result of a tiny change in the DNA, which results in a lamin-A protein that’s missing 50 amino acids near one end. The shortened lamin-A protein is called progerin, and it alters the structure, shape and stability of the nuclear membrane.
The fragile structures formed by progerin lead to progressive damage to the nucleus, which kills cells. Progerin also alters which genes are turned on or off and affects the ability of cells to repair breaks in the DNA of the genome.
Children with progeria appear normal at birth and in early infancy but fail to grow at the normal rate and to gain weight. They develop characteristic facial features including prominent eyes, a thin nose and lips, a small chin and protruding ears. Other characteristics of progeria include alopecia (hair loss), joint abnormalities, aged appearance of the skin and loss of fat underneath the skin.
Beginning in childhood, those with progeria develop severe hardening of the arteries, or arteriosclerosis, increasing the chances of experiencing heart failure, heart attacks or strokes. These children are normal in terms of intellectual and motor development.
The new drug, called Zokinvy, is made by Eiger BioPharmaceuticals, a U.S. company that develops treatments for rare diseases. Zokinvy works by stopping the complicated process that destabilizes the nucleus in the cells of people with progeria.
The drug has been used to treat more than 80 children in clinical trials, and it is well-tolerated. When compared to untreated progeria patients, Zokinvy increased their lifespan by three months during the first three years of treatment and an average of 2.5 years after 11 years of treatment. This new drug isn’t a cure, but it can extend the lives of progeria patients.
This drug is a small step in the right direction, and perhaps additional therapeutics will be developed in the future that can do even more for patients suffering from the rare disease. Cheers to companies like Eiger that are working on rare diseases like this.