By Jeanne Whalen
GlaxoSmithKline strengthened its focus on rare diseases today by targeting one of the rarest: ADA severe combined immune deficiency, one form of so-called “bubble boy disease.”
ADA-SCID, which affects only about 350 children worldwide, is caused by a genetic defect that leaves kids without a functioning immune system, making them extremely vulnerable to infection and early death.
The standard treatment today is a bone marrow transplant, which gives the patient new stem cells that, with luck, will start producing the blood cells needed to make the immune system function. But closely matched donors are hard to find, and the patient’s body often rejects the transplanted cells.
Glaxo has licensed an experimental gene therapy from two Italian institutions that aims to fix the stem cells in the patient’s own bone marrow. Stem cells are removed and a healthy gene is inserted before the cells are returned to the body. Glaxo and its partners believe that using the patient’s own cells will reduce the risk of rejection.
The therapy has demonstrated “potential” in phase 1 and 2 studies, Glaxo says. The drug giant and the two institutions — Fondazione Telethon and Fondazione San Raffaele — plan to see if the same technique might be used in treatments for a range of other rare diseases, from metachromatic leukodystropy to Wiskott-Aldrich Syndrome. (Trials for those two diseases are now recruiting patients.)
The partnership is part of Glaxo’s growing push into the rare disease market, Marc Dunoyer, global head of rare diseases, told journalists on a conference call today. About 70% of the 6,000-8,000 rare diseases that have been identified have genetic origins, and many have clear molecular targets. As Dow Jones Newswires reports, Dunoyer said his rare disease unit will focus on four areas: metabolism, immuno-inflammation, central nervous system and hematology. DJN notes that “he declined to say how much money the division would spend or whether acquisitions were part of its drug development strategy.”