Synosia to test Nitisinone for treatment for Parkinson's Disease

Synosia Therapeutics, Basel, Switzerland is set to start a proof-of-mechanism, clinical trial to evaluate the efficacy and safety of a therapy that could be used to treat Parkinson's disease.

Nitisinone (SYN-118) is a potent and selective inhibitor of hydroxyphenylpyruvate dioxygenase (HPPD). This enzyme in the primary pathway is responsible for the catabolism of tyrosine, the precursor of the neurotransmitter dopamine. This novel intervention point in the dopamine pathway offers the potential to induce a sustained increase in dopamine synthesis in the brain of Parkinson's patients to improve the control of motor symptoms with an improved side effect profile compared to current therapy.

The dose-escalation trial in Parkinson's patients is being conducted at the Karolinska Institutet in Stockholm using positron emission tomography (PET) and clinical ratings such as the Unified Parkinson's Disease Rating Scale to evaluate efficacy.

"We know from extensive clinical studies and patient experience with nitisinone that the drug produces pronounced and reliable elevations in the levels of tyrosine, a precursor of dopamine," said Stephen Bandak, Synosia's chief medical officer. "We are now evaluating whether this results in increased synthesis of dopamine in the brain of patients with Parkinson's."

Synosia's chief executive Officer and president Ian Massey said: "This data-rich, efficient trial will test our hypothesis on the pharmacology of the drug and help to zero in on the right dose for a Phase II efficacy study."

Nitisinone was discovered and developed by Syngenta, which has granted licensing rights to Swedish Orphan International (SOI) for orphan indications. In 2007, Synosia obtained rights from Syngenta to develop and commercialise nitisinone in all non-orphan indications.

Synosia Therapeutics develops and intends to commercialise innovative and clinically differentiated products for unmet medical needs in psychiatry and neurology.