While progress has been made in recent years, the nature of diseases such as Alzheimer’s and Parkinson’s continues to vex drug developers and leaves a growing global patient population with high unmet needs. Alzheimer’s and Parkinson’s are the two most common types of neurodegenerative diseases, and the prevalence is on the rise. More than 55 million people live with dementia worldwide, of which 60-70% have Alzheimer’s Disease, according to the World Health Organization (WHO) statistics from 2023. The US-based Parkinson’s Foundation estimates that about ten million people suffer from Parkinson’s Disease globally.

Both of these diseases have a complex pathophysiology. For drug developers looking at either disease, the blood-brain barrier (BBB) that regulates the passage of substances from the blood stream into the brain makes it difficult to reach the brain with pharmaceuticals. Once reached, drug delivery methods still struggle to ensure that the right part of the brain is targeted. 

Excitement ran high when the US Food and Drug Administration (FDA) granted approval for Stockholm-based BioArctic and Eisai Inc.’s drug Leqembi (Lecanemab) in 2023. It is a monoclonal antibody that targets and removes one hallmark of Alzheimer’s disease – amyloid beta plaques on the brain. Eli Lilly’s Kinsula (Donanemab) – which also targets amyloid beta plaque – received FDA approval in 2024 and is still waiting for the green light from the EMA. 

However, more needs to be done to tackle the many different responses the brain has to the progression of neurodegenerative diseases. 

A vaccine

One company that’s brought its innovative approach into clinical trials is Gothenburg-based Alzinova. Their lead candidate ALZ-101 is a vaccine that stimulates the production of antibodies specific to toxic accumulations of amyloid-beta oligomers in the brain. The vaccine showed promising results when the primary analysis of the Phase Ib study data was released in January, and a Phase II clinical trial is set to start later this year.

If we can administer an immunization once every 3-4 months with Alzinova’s vaccine, that would make a huge difference compared to the present reality.

Should the vaccine enter the market, it would not only offer a new treatment option to an underserved patient population, but would also save costs for the healthcare system and time and inconvenience for the patients.

Tord Labuda, CEO, Alzinova

“The cost to society is enormous – Alzheimer’s alone costs nearly 1% of GDP globally. If we can administer an immunization once every 3-4 months with Alzinova’s vaccine, that would make a huge difference compared to the present reality where patients need an uncomfortable infusion at the clinic once every two weeks or monthly. According to our calculations, the cost of administration of treatment with our vaccine would land at around 2% compared to current options,” Alzinova’s CEO Tord Labuda says.

He clarifies that the estimate is for the administration cost specifically, not the drug cost which is in line with current therapies.

A discovery phase program

Across the Baltic Sea, Polku Therapeutics, a Helsinki-based biotech startup which launched last year, is running a discovery phase program for Parkinson’s Disease and tauopathies, including Alzheimer’s Disease. Their program targets the accumulation of abnormal protein aggregates like tau and alpha-synuclein in the brain. 

The drugs that have been approved recently focus on amyloid beta plaque, which is important. But in addition to that, there is tau protein, which we’re targeting, and both play a role.

“Until recently, there were dozens and dozens of candidates that had gone as far as phase II clinical trials, but few, if any, that progressed beyond that. So there’s a real dearth of reliable treatments for patients in neurodegeneration,” says Simon Bennett, CEO of Polku. 

Simon Bennett, CEO, and Sebastian Soidinsalo, Director of Operations, Polku Therapeutics

The young company is currently investigating several compounds for a single target, with its sight set on selecting a candidate to move forward with in the next 12-18 months.

“The drugs that have been approved recently focus on amyloid beta plaque, which is important. But in addition to that, there is tau protein, which we’re targeting, and both play a role. There is a hypothesis that tau is maybe even more important, but that remains to be seen when these clinical trials that target intracellular tau buildup are finalized,” Sebastian Soidinsalo, Director of Operations at Polku says.

Soidinsalo feels that it’s a personal mission to work towards better treatment options for neurodegenerative diseases.

“From the patient perspective, it can be quite a daunting diagnosis, as you can imagine. Little by little, your cognitive functions are stripped away. There’s little we can do about it at the moment, and everybody hopes that a pharmaceutical will be developed that stops that progression and can offer patients more healthy life years,” he says.