Alzheimer’s has long been one of thorniest problems in pharmaceutical research, with companies pouring millions into research with limited success to show for it. But that may finally  be changing.

Biotech companies have been experimenting with various vaccines to combat Alzheimer’s, but often those experiments have led to terrible side effects.

United Neuroscience Ltd., a biotech startup based in Dublin, recently released the results of a small clinical trial of UB-311, a new vaccine it’s developing to help combat Alzheimer’s disease—and so far, according to reporting by Bloomberg, the results have been positive.

It’s very early days—the drug is only in Phase 2 of its clinical trial, and the pool of patients involved in the study is quite small (only 43 individuals with “mild Alzheimer’s disease” were included). But despite the trial’s modest size and findings, the researchers remain tentatively optimistic. “We can’t make any claims yet,” Mei Mei Hu, the CEO of United Neuroscience told Bloomberg, “but we’re pointing in all the right directions.”

Scientists still don’t know exactly what causes Alzheimer’s, but there’s evidence to suggest that the disease is exacerbated by inflammation in the brain—which is sometimes caused by proteins, particularly of the amyloid or tau family, that build up in the body and around neurons.

UB-311 is a little different than your standard vaccine.

For the past two decades, biotech companies have been experimenting with various vaccines to combat Alzheimer’s, but often those experiments have led to terrible side effects. Patients’ bodies have resisted treatment, launching immune responses that have led to severe brain swelling and impairment. That’s because, for the most part, traditional vaccines are meant to target infectious diseases, which come from pathogens outside the body—like the flu, or polio.   

But UB-311 is a little different than your standard vaccine. UB-311 is what the researchers refer to as an endobody vaccine, meaning that it has been designed to target a substance—in this case, amyloid proteins—produced by the body. The goal of such a vaccine would be to enable the body “to develop its own defense agents of chronic disease,” as United Neuroscience’s website explains.

The Phase 2 of UB-311’s trial showed that 96% of patients responded to the drug without any serious side effects. On top of that, patients demonstrated improved brain function, and protein plaque found on their neurons was reduced.

While the cure for Alzheimer’s is still a very long way off, these results are encouraging. Next, the company is planning a third phase of testing for UB-311, which will involve widening the scope of study and increasing the number of participants.

United Neuroscience also has two other ambitious trials in works: one targeting tau, the other family of proteins associated with Alzheimer’s, and one for UB-312, a vaccine aimed at fighting Parkinson’s disease.