For families living with neurodegenerative disease, the hardest part is not always the diagnosis. It is the slow erosion that follows: memory fading, personality shifting, independence shrinking.

It unfolds quietly. First, forgotten appointments. Then repeated questions. Then moments when a familiar face no longer feels familiar.

The illness does not isolate itself to one body. It rearranges the lives around it. Partners become caregivers. Children become decision-makers. Conversations grow shorter. Patience grows thinner. Guilt creeps in, for being tired, for wishing things were easier, for missing the person who is still physically there.

Neurodegeneration is rarely a single patient story. It is a family condition, stretching across kitchens, hospital corridors, and years that feel longer than they should.

Dublin-based Aerska has raised $39 million in fresh funding to battle one of the biggest scientific barriers standing between patients and meaningful treatment: getting advanced genetic medicines into the brain.

The round was co-led by EQT Life Sciences and age1, two investors known for backing high-risk, high-impact biotech. Their bet is not just on a platform, but on the possibility that diseases once managed only at the margins could eventually be slowed at their root.

Crossing the brain’s final frontier

Think of the brain as a house with very strict security at the door. That security system, called the blood-brain barrier, protects us from harmful substances in the blood. The problem is that it is so strict that it also blocks many medicines. 

So even if scientists create a smart treatment that can “turn off” a harmful gene linked to diseases like Alzheimer’s, the drug often cannot physically get inside the brain cells where it needs to work.

Aerska is trying to solve that access problem.

Instead of injecting medicine directly into the brain, which is invasive and risky, they are developing a way to send it through the bloodstream like a normal injection. Their technology acts like a special pass that lets the treatment cross the brain’s security gate. Once inside, the medicine can reduce the production of the proteins that drive disease.

In simple terms, the science to switch off bad genes already exists. The hard part is delivery. Aerska is building the delivery vehicle.

The company’s early focus includes genetic drivers of conditions such as Alzheimer’s disease and Parkinson’s disease. Both remain incurable. Existing drugs largely manage symptoms rather than altering the course of decline.

RNA interference, by contrast, aims to reduce the production of disease-causing proteins themselves. It is a strategy that addresses biology upstream, not downstream.

Longevity, but grounded in reality

Longevity has become the “American dream” in European biotech, yet most serious investors are looking less at life extension and more at healthspan,  years lived with clarity and autonomy.

That is the space Aerska is positioning itself in. The goal is not abstract immortality. It is more time at home, more recognisable faces, and more preserved dignity.

The $39 million will fund preclinical development and early clinical steps. The scientific obsacle remain significant, and neurological drug development has humbled many before. But systemic RNA delivery to the brain, if proven safe and effective, would mark a structural shift in how these diseases are approached.

For now, Aerska represents something simpler: a European biotech choosing to confront one of medicine’s most stubborn frontiers,  not with incremental symptom control, but with the ambition to change the trajectory itself.