(Reuters) – Shares of U.S. gene therapy companies sank on Thursday after drugs developed by two small firms failed to show promise in separate clinical trials, underscoring the challenges in an emerging, lucrative field of biotech.
Experimental treatments developed by Sangamo Therapeutics Inc and Solid BioSciences did not show enough clinical benefit to patients in early-stage trials testing the drugs to treat rare disorders.
Sangamo said interim results showed that genome-edited liver cells were able produce the IDS enzyme, the lack of which is a genetic mutation that leads to Hunter syndrome, which causes skeletal and respiratory abnormalities.
Still, investors parsing the clinical data sent shares of Richmond, California-based Sangamo plunging 37 percent to $7.53.
“Investors may have expected some clinical efficacy data,” Wedbush Securities analyst Liana Moussatos said. “Investors want to know if that level of enzyme is enough to show a clinical benefit and there was nothing about that in (Sangamo’s) press release.”
The data wasn’t “inherently bad,” and there could be additional data this year showing clinical benefit, Moussatos added.
Sangamo’s drug was also being tested in patients with Mucopolysaccharidosis Type I, or Hurler syndrome, another rare disorder.
Gene editing uses various technologies to target the DNA using different types of proteins.
Meanwhile, Cambridge, Massachusetts-based Solid BioSciences said interim data from its gene therapy showed low levels of an important enzyme in patients with a muscle wasting disorder, sending its shares sliding 63 percent to $8.26.
Shares of other companies using gene-editing technologies, CRISPR Therapeutics, Editas Medicine and Intellia Therapeutics, fell between 7 and 10 percent in afternoon trading.
Reporting by Manas Mishra, Ankur Banerjee and Saumya Sibi Joseph in Bengaluru; Editing by Sai Sachin Ravikumar