Glycomine Secures $115M for Rare Disease, Plans Mid-Year Phase II Launch

California-based biopharmaceutical company Glycomine has secured $115 million in a Series C funding round to advance its primary treatment for phosphomannomutase-2 congenital disorder of glycosylation (PMM2-CDG) into Phase IIb trials. This rare genetic disorder, characterized by a wide array of symptoms and bodily impact, currently lacks an FDA-approved treatment. Glycomine's CEO, Steve Axon, revealed that PMM2-CDG is the most prevalent among glycosylation disorders, which involve the attachment of sugar chains to proteins. Axon estimates the disorder affects up to 20,000 individuals across the U.S. and Europe, a significant figure for a rare disease, comparable to the population size affected by Pompe disease.

Glycomine plans to utilize the newly raised funds to propel its leading molecule, GLM101, into a randomized, placebo-controlled Phase IIb trial. Earlier in 2024, the company reported promising results from a Phase II trial involving nine adult and adolescent patients, noting improvements in symptoms such as ataxia, a neurological condition linked to muscle control loss. This improvement in ataxia serves as the clinical endpoint for validating GLM101's effectiveness.

The upcoming Phase IIb trial will enroll 40 to 50 participants, ranging from two years old to adults, and is expected to commence by mid-year, with outcome data anticipated by mid-2026. Following this, Glycomine aims to engage with the FDA regarding regulatory filings. Although further trials might be requested by the FDA due to the absence of existing treatments for PMM2-CDG, Axon expressed confidence in the potential for productive engagement with regulatory bodies.

PMM2-CDG is typically diagnosed in infancy and is caused by various mutations affecting the phosphomannomutase 2 protein, crucial for glycosylation. The disorder's symptoms and severity can differ, but most patients experience some neurological impairments and language and motor challenges from an early age. Additional common symptoms include ataxia, seizures, immune dysfunction, and coagulation issues. The disorder carries a 20% mortality rate within the first five years of life, primarily due to organ failure and failure to thrive, with glycosylation being central to these clinical manifestations.

GLM101 functions as a lipid nanoparticle–delivered mannose-1-phosphate (M1P) replacement therapy. Patients with the phosphomannomutase 2 mutation suffer from a significant deficiency in M1P. The delivery system using lipid nanoparticles extends the half-life of M1P in the bloodstream from a few minutes to over 80 hours, a crucial aspect noted by Axon.

While Glycomine is exploring mRNA treatments to develop enzyme replacements for PMM2-CDG, the company is currently focused on directly replacing the missing molecule through GLM101, a strategy Axon described as straightforward and effective. He emphasized the broad biodistribution achieved with their current approach.

Since its inception, Glycomine has conducted multiple funding rounds, beginning with a $12 million Series A in 2016. This was followed by two Series B rounds, raising $33 million in 2019 and $68 million in 2021, respectively. These financial infusions have been instrumental in advancing the company's research efforts and moving closer to clinical applications.