Gene Therapy Safe for HIV Patients

Experimental gene therapy is safe for HIV

(RxWiki News) It's hoped that gene therapy – altering the genetic code in a patient's cells – will someday cure disease. But today, it's enough to know that it's not causing additional illness.

A decade-long study has found that HIV-positive patients treated with genetically modified cells are healthy, and most study participants still have the modified cells in their bodies.

It's a step in the right direction, because similar treatments have caused leukemia in the past.

"Gene therapy still holds hope for an alternative to anti-HIV drugs."

The study was conducted by a team of researchers at the University of Pennsylvania, led by Dr. Carl June, MD, a professor of Pathology and Laboratory Medicine at Penn Medicine.

The results are based off three trials that ran between 1998 and 2002, in which 43 patients received gene therapy. The doctors took blood from patients, genetically reprogrammed a type of immune cell called a T cell that's active in HIV, and injected the modified blood back into the patients.

The modified T cells were supposed to kill HIV cells, to ultimately eliminate HIV from the body. These cells multiplied in the body, increasing the ranks of cells that could fight the virus. 

The idea is that an injection of killer HIV cells could replace the expensive, and life-long regimen of drugs now required to keep an HIV-positive individual healthy.

"If you have a safe way to modify cells in patients with HIV, you can potentially develop curative approaches," June said in a press release. "Patients now have to take medicine for their whole lives to keep their virus under control, but there are a number of gene therapy approaches that might be curative."

While the treatment did not work to eliminate HIV,  the researchers now know that the treatment is safe. There's still a ways to go until gene therapy becomes an available and effective treatment.

In similar studies, the modified cells have caused unexpected mutations that developed into leukemia, leaving the patients worse off.

The researchers are also heartened by the fact that the modified genes remained in the blood of 41 out of 43 patients. It proves that gene therapy still holds possibilities for long-term treatment.

Dr. June said that T cell-based gene therapy could go beyond HIV to focus on other diseases, such as arthritis.

Patients who participated in gene therapy had no adverse events immediately after the treatment, and according to a press release, there were no major long-term side effects.

The study was published in Science Translational Medicine in May 2012.

Review Date: 
May 8, 2012