Promising new gene therapies are revolutionizing care and improving outcomes for children with rare disorders

The power of gene therapy to transform the lives of sick children is revolutionary, and physician-scientists at Children’s Hospital of Philadelphia (CHOP), along with their collaborators at the University of Pennsylvania, have been on the front lines for years.

2017 marked gene therapy’s most promising year to date. After decades of research into how to modify an individual’s DNA to treat disease, the first gene therapies were approved by the U.S. Food and Drug Administration (FDA).

These new therapies aim to treat the underlying genetic cause of rare and life-threatening diseases. The first two FDA-approved gene therapies were developed at CHOP, and a third promising treatment has its roots here.

Cell therapy for ALL

Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer. It’s also one of the most treatable. Eighty-five percent of children with ALL are cancer-free after two years of standard chemotherapy.

Unfortunately, about 15 percent of children with ALL have a type of disease that is resistant to even the most intense chemotherapy regimens. At CHOP, Stephan Grupp, MD, PhD, Director of the Cancer Immunotherapy Program and Section Chief, Cellular Therapy and Transplant, and his colleagues were determined to change the outcomes for that 15 percent.

In 2012, the Cancer Immunotherapy team treated the first pediatric patient with a then-experimental therapy that reprograms a child’s own immune system to find and fight cancerous cells. The Cancer Immunotherapy Program went on to treat more than 170 patients in clinical trials — with a 93 percent remission rate.

Based on those impressive results, in August 2017, the immunotherapy called CAR T-cell therapy became the first-ever cell therapy to be approved for use by the FDA.

This history-making development has shifted the paradigm for pediatric cancer treatment, opening up new therapy possibilities and restoring hope to families who have children with treatment-resistant cancer.

Learn more about the pioneering CAR T-cell studies at CHOP.

Eyeing restored vision

An estimated 1,000 to 2,000 people in the United States have a gene mutation that causes visual impairment at infancy or early childhood and often total blindness by mid-life. In December 2017, CHOP celebrated the FDA’s approval of Spark Therapeutics’ innovative one-time gene therapy for the treatment of this rare, inherited form of retinal blindness.

The approval highlighted the vital role of pediatric research in developing breakthrough cures, as the therapy grew out of 10 years of research conducted at CHOP’s Raymond G. Perelman Center for Cellular and Molecular Therapies (CCMT).

Spark Therapeutics is a Philadelphia biotechnology company created in 2013 by Children’s Hospital in an effort to accelerate the timeline for bringing new gene therapies to market. The initial research was conducted under the direction of then-CHOP-researcher Katherine A. High, MD, a gene therapy pioneer who directed the CCMT and is now Spark’s president and head of research and development.

Learn more about this novel new treatment for inherited blindness.

Clotting cure for hemophilia B

Children with hemophilia, a congenital bleeding disorder, need lifelong vigilant monitoring because cuts and spontaneous bleeding can be life-threatening. Caused by a malfunction in blood-clotting protein, hemophilia affects an estimated 1 in 5,000 males. There is no currently no cure for hemophilia; and ongoing care requires regular intravenous treatments of clotting factor to prevent bleeding and protect an individual’s joints.

At CHOP, Hematologist Lindsey A. George, MD, oversaw clinical trials for a novel bioengineered gene therapy that has shown extremely promising results for adults with hemophilia B.

A single intravenous (IV) infusion of the bioengineered gene therapy has enabled participants to produce sustained levels of clotting factor in their own blood. Nearly all the patients were able to eliminate the need for IV infusions of manufactured clotting factor and no longer experienced uncontrolled bleeding.

Clinical trials for the IV gene therapy were funded by Spark Therapeutics and Pfizer, and are an outgrowth of years of research by Katherine A. High, MD, and others at CHOP’s Raymond G. Perelman Center for Cellular and Molecular Therapies (CCMT).

These exciting clinical trials will now progress to the next phase. If trials continue to show the treatment is safe and effective, the lives of children with hemophilia could be transformed as they are freed from the fear of dangerous bleeding events.

Learn more about one-dose gene therapy for hemophilia.

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