Lysogene's lead gene therapy flunks phase 2/3 trial almost a year after Sarepta walked out

With cash running out and a number of strategic options under consideration to stay afloat, Lysogene was banking on a clinical home run from its lead asset to woo investors. But new data presented by the company are anything but a splash. 

The company’s top pipeline candidate, LYS-SAF302, failed its phase 2/3 trial among patients with mucopolysaccharidosis type IIIA (also known as Sanfilippo syndrome), a neurodegenerative disease that can spur a wide range of bodily dysfunction, including infections, dementia, sleep disturbances and propensity to chew on objects. Much of the symptoms begin to appear in early childhood.

The company reported Friday that among the six youngest participants in the trial— kids younger than 30 months—there was a statistically significant improvement in cognitive function compared to natural history two years after dosing. Among the remaining 12 participants—"the main cohort"—a treatment effect wasn’t found. Development was measured using one of two different scales that assess neurodevelopmental and cognitive delay. 

The results come almost a year after Sarepta decided to walk away from a deal to hold ex-Europe rights to LYS-SAF302, a collaboration that cost $15 million in upfront cash in addition to $125 million in biobucks. At the time, Lysogene said the termination had to do in part with “unsuccessful discussions” regarding the transferring of commercial supply of the therapy back to Lysogene. 

But the fact of the matter is that Lysogene is facing a significant cash crunch given its clinical ambitions. As of the end of September, the company had roughly $6.3 million on hand, enough to last until the end of January. Lysogene is bullish that the data presented today, particularly the encouraging results in children under 30 months, will be enough to fundraise on. The company said in its announcement that strategic discussions are “progressing” with a priority placed on landing a new licensing deal. 

The only additional clinical asset in Lysogene's pipeline is LYS-GM101, a treatment for the genetic neurological disorder GM1 gangliosidosis. The condition progressively destroys nerve cells in the brain and spinal cord. In late September, the company said (PDF) that it had enrolled five patients for the initial phase 1 trial focused on safety. If all goes well, Lysogene expects to begin enrollment for an additional 12 patients in early 2023.