Oak Hill Bio Raises $32.5 Million to Advance ASO in Angelman Syndrome

Rare Daily Staff

Oak Hill Bio announced it has closed a $32.5 million series A financing to advance its experimental antisense oligonucleotide therapy, rugonersen, into a pivotal phase 3 study for Angelman syndrome.

Balyasny Asset Management, venBio, and Janus Henderson Investors co-led the round, with participation from KCap Biotechnology Fund.

Angelman syndrome (AS) is a rare genetic neurodevelopmental disorder that causes severe cognitive and physical impairment. It is characterized by global developmental delay, intellectual disability, epilepsy with characteristic electroencephalogram abnormalities, ataxia, tremor, hyperactivity, limited speech, and sleep disturbances. Symptoms typically emerge in infancy and persist throughout life.

Angelman syndrome is caused by deletions or mutations in the maternal ubiquitin protein ligase E3A (UBE3A) allele. In neurons, the paternal UBE3A allele is epigenetically silenced by a long noncoding antisense RNA (UBE3A-ATS), leaving no functional UBE3A expression. UBE3A is essential for normal brain development and function. Loss of UBE3A activity in central nervous system neurons leads to the accumulation of damaged or misfolded proteins, disrupting neuronal maturation, function, and synaptic pruning.

Rugonersen was originally developed by Roche as a highly potent and specific therapy designed to restore UBE3A expression in neurons. Several former members of the rugonersen development program have joined Oak Hill Bio to lead its continued advancement.

In connection with the financing, Oak Hill Bio appointed new members to its board of directors, including Doug Fambrough, founder and portfolio manager of KCap Biotechnology Fund; Rich Gaster, managing partner at venBio; and Sandeep Kulkarni, co-founder and CEO of Zura Bio.

“We believe rugonersen has best-in-class, disease-modifying potential and clearly demonstrates Oak Hill Bio’s ability to identify and acquire assets with significant therapeutic and commercial promise,” said Doug Fambrough, a member of the board of directors.

Photo: Doug Fambrough, founder and portfolio manager of KCap Biotechnology Fund and a member of the Oak Hill Bio board