Gene Therapy Frees 6 Patients From 35 Daily Pills

Six adults who took up to 36 pills every single day to manage a rare genetic disease are now living nearly medication-free, thanks to a gene therapy developed at the University of California, San Diego.

The patients have cystinosis, an inherited disorder that causes a harmful amino acid to build up in their organs. Without constant medication, the disease destroys kidneys, eyes, muscles, and other tissues. Four of the six patients had already needed kidney transplants before joining the trial.

The new treatment, called CTNS-RD-04, works by fixing the problem at its source. Scientists remove stem cells from each patient's bone marrow, add a working copy of the faulty gene, and infuse the corrected cells back into the body. These cells travel throughout the body and start producing the missing protein that clears away harmful buildup.

The results published this week in the New England Journal of Medicine show remarkable progress. Harmful cystine levels dropped by 25 to 86 percent in all six patients over two years. The earliest patient has now been monitored for more than five years and remains stable.

Before treatment, patients swallowed an average of 36 pills daily and needed eyedrops every waking hour. Most patients have now stopped all oral medication. Their kidney transplants continue functioning normally, and tests of brain function, coordination, and motor skills stayed stable or improved.

"We have stable tissue function in most of the patients, and even some improvements," said Dr. Stephanie Cherqui, the pediatrics professor who led the research. The team spent years testing the approach in mice starting in 2007, and the animal results worked beyond their expectations.

Two patients with lower levels of the corrected gene in their cells needed to restart low doses of medication. This suggests higher amounts of the gene therapy may work even better. The treatment caused no serious side effects related to the gene therapy itself.

The Ripple Effect

This success opens doors for treating other genetic diseases that affect multiple organs. Cherqui's team is already testing similar stem cell gene therapies for Danon disease and Friedreich's ataxia, two other conditions that current medications can't cure.

Pharmaceutical giant Novartis acquired the gene therapy in 2023 and launched a larger trial in children last year. If those results match this success, thousands of families could escape the exhausting daily medication burden that defines life with cystinosis.

For diseases like cystinosis that damage organs throughout the body, gene therapy once seemed impossible. This trial proves that smart science and patient stem cells can reach everywhere the disease goes.

One treatment is replacing 13,000 pills per year and giving patients their lives back.