When will the medication to slow the progression of the disease be available?

‘Disease-modifying medication’ refers to treatment that reduces or otherwise prevents the progression of the disease. There are currently many studies underway, some involving drugs that are already authorised, whilst others are entirely new. However, it is difficult to prove a potential disease-modifying effect that is distinct from the symptom-relieving effect of increased dopamine in the brain, as it is a deficiency that causes the symptoms.

According to the regulations governing the development of a completely new drug, it takes at least 3–5 years to demonstrate safety, tolerability and proven efficacy, but it may take longer if it is difficult to distinguish between symptom relief and disease-slowing effects.