Preliminary results of Sangamo Therapeutics' gene-editing treatment indicate that the firm may have been able to make in-body gene edits, but that these alterations may not have been enough to call the therapy a success, the Associated Press reports.
The firm has been exploring using zinc finger nucleases to treat patients with the metabolic disorders Hunter syndrome and Hurler syndrome. In its Phase 1/2 CHAMPIONS Study, Sangamo is treating patients with low, medium, or high doses of its zinc-finger-based gene therapies, and the treatment was first given to Brian Madeux in 2017 to treat his Hunter syndrome. Preliminary results reported this past fall suggested one of its zinc-finger-based treatments could be working, though it was early to say for sure.
The AP now reports that Paul Harmatz of the University of California, San Francisco's Benioff Children's Hospital Oakland, who is working on the trial, presented results that showed that two patients who received a medium dose of on treatment exhibited signs of low-level gene editing, while the patient who received the low dose did not. It notes that results from patients who received the high dose are expected later this year.
However, the AP adds that though the patients who showed signs of gene editing had higher levels of their missing enzyme, those levels didn't reach normal.