Prothena achieves $60m milestone as part of Roche collaboration

Dublin-headquartered biotech company Prothena has achieved a $60m milestone payment as part of its collaboration with Roche, after dosing the first patient in a new phase 2b study of prasinezumab .

Prasinezumab is a monoclonal antibody (mAb) designed to target alpha-synuclein, a protein found in neurons that can build up and spread from cell to cell. This results in the neuronal dysfunction and loss that ultimately leads to Parkinson’s disease.

This mAb is at the centre of a collaboration between Prothena and Roche, which was initially agreed in 2013 with the aim of developing and commercialising antibodies that target alpha-synuclein.

In addition to this most recent milestone payment, Prothena has already received $75m in payments from Roche as part of their collaboration.

The deal saw Roche pay Prothena an upfront fee and near-term clinical milestones totalling $45m, with Prothena eligible to receive additional payments of up to $380m in the US.

The biotech company could also receive further payments of $175m for milestones reached outside the US, potentially taking the total payment to $600m.

The phase 2b PADOVA study of prasinezumab has been advanced following the ‘positive signals of efficacy’ in the phase 2 PASADENA trial.

Although the PASADENA study did not meet its primary objective of slowing the progression of motor and non-motor symptoms over the first year of treatment, the drug showed signs of efficacy on secondary and exploratory measures.

This included a reduction in disease progression in both prasinezumab arms compared to placebo. In addition, prasinezumab reduced decline motor function by 35% when compared to placebo after one year of treatment, using the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) Part III.

Patients treated with prasinezumab also demonstrated a significant delay in time to clinically meaningful worsening of motor progression versus placebo over one year.

The PADOVA study is designed to evaluate the efficacy and safety of prasinezumab in patients with early Parkinson’s disease who are on stable symptomatic medication.

It will enrol approximately 575 patients who will be randomised to either prasinezumab or placebo via intravenous infusion every four weeks.

The study’s primary endpoint is the time to meaningful progression on motor signs of disease, assessed as a ≥ 5 point increase from baseline in the MDS-UPDRS Part III score.