Prothena (PRTA) The Citizens Life Sciences Conference 2026 summary

Company overview and pipeline highlights

• Focuses on diseases caused by dysfunctional proteins, with a differentiated scientific approach and both partnered and unpartnered programs since its 2012 spin-out.

• Multiple phase III programs are ongoing, including partnerships with Roche (Parkinson’s, alpha-synuclein), Novo Nordisk (ATTR cardiomyopathy), and Bristol Myers Squibb (tau protein, MTBR region).

• CYTOPE technology aims to target previously undruggable intracellular proteins, exemplified by TDP-43 for ALS.

Clinical and financial milestones

• Earned $50 million milestone from Novo for enrollment achievement, with potential for $55 million from Bristol if PRX019 advances to phase II by year-end.

• Announced a share repurchase program of up to $100 million for 2026, not included in current year-end cash guidance.

• Partnered programs could yield up to $3 billion in milestones, excluding royalties.

Key clinical data and timelines

• Roche’s prasinezumab in Parkinson’s: phase III ongoing, with new five-year open-label extension data and additional PADOVA phase IIb data to be presented at AD/PD 2026.

• Novo’s ATTR cardiomyopathy program showed nearly 50% NT-proBNP reduction at high dose, prompting phase III advancement; data expected around 2029.

• Bristol’s anti-tau program (TargetTau-1) phase II data expected first half of next year; PRX019 phase I completion and decision on phase II by end of this year.