The raise will go toward trialing the company’s lead drug for phosphomannomutase-2 congenital disorder of glycosylation, a rare disease that affects the entire body and produces a wide range of symptoms.
California-based biopharma Glycomine announced a $115 million Series C raise Wednesday to push its lead rare disease molecule into Phase IIb trials.
“We’re working on glycosylation disorders, putting sugar chains on proteins. There are hundreds of those,” CEO Steve Axon told BioSpace in an interview. The disorder that Glycomine is targeting is, according to Axon, the largest of that group: phosphomannomutase-2 congenital disorder of glycosylation, or PMM2-CDG, for which there is no FDA-approved treatment.
“We think it’s maybe up to 15- 20 thousand patients in [the] U.S. and Europe, which is a relatively large population for a rare disease,” Axon said, likening the demographic size to Pompe disease.
Glycomine is using the new funds to push its lead molecule, GLM101, into a randomized, placebo-controlled Phase IIb trial. In early 2024, the company announced “encouraging” data for a Phase II trial for the drug, showing improvements for nine adult and adolescent patients in ataxia, neurological symptoms characterized by loss of muscle control. Improving ataxia is the clinical endpoint for GLM101’s efficacy studies.
The Phase IIb study, comprising 40 to 50 patients from two years to adults, is set to start by the middle of this year, with data expected sometime in mid-2026. Then, Glycomine will approach the FDA about filings. The FDA could also ask for more trials, but as there aren’t any other treatments for the disorder, “we’re hopeful for productive regulatory discussions,” Axon said. “We think we’re in good shape with the FDA.”
PMM2-CDG is a genetic disease often diagnosed in infancy. It involves a range of mutations that all affect one protein, phosphomannomutase 2, which is involved in the glycosylation process. Symptoms and severity can vary and most patients experience some sort of neurological dysfunction, as well as language and motor issues from childhood. Ataxia, seizures, immune dysfunction and coagulation issues are also common with PMM2-CDG.
“PMM2 has a 20% mortality rate within the first five years of life, from organ failure and failure to thrive,” Axon said. “And glycosylation is at the core of all of [those clinical signs].”
GLM101 is a lipid nanoparticle–delivered mannose-1-phosphate (M1P) replacement therapy. Because of the phosphomannomutase 2 mutation, patients are critically short of M1P. The lipid nanoparticle delivery vehicle is critical, Axon said, because it extends M1P’s half life in the bloodstream from a few minutes to upwards of 80 hours.
Glycomine is also investigating mRNA treatments to produce enzyme replacements for PMM2-CDG, but so far the company is sticking with simply replacing the missing molecule, an approach Axon called simple and elegant.
“What we’ve settled on is something that has really wide biodistribution,” he said.
The company has gone through multiple raises of increasing sizes on its journey to the clinic. A $12 million Series A in 2016 started things off, followed by two successive Series B raises of $33 million in 2019 and $68 million in 2021.
