Oculis’ Privosegtor Gains EMA PRIME Designation, Begins Three-Trial PIONEER Program
Privosegtor received EMA PRIME designation for optic neuritis, following Breakthrough Therapy from FDA and Orphan Drug status, supporting its potential as a first-in-class neuroprotective therapy. Phase 2 ACUITY showed substantial LCVA improvement and anatomical protection; global PIONEER registrational program with three trials began, with PIONEER-1 initiated in Q4 2025.
1. PRIME Designation Details
Privosegtor has been granted PRIME designation by the European Medicines Agency for the treatment of optic neuritis, a sight-threatening condition with no approved neuroprotective therapies. This follows Breakthrough Therapy status from the FDA and Orphan Drug designations, providing early scientific and regulatory support to accelerate clinical development and evaluation.
2. Phase 2 ACUITY Trial Results
In the ACUITY Phase 2 trial, Privosegtor combined with steroids delivered substantial low-contrast visual acuity improvements alongside anatomical and biological neuroprotective benefits versus placebo and steroids. The magnitude of effect impressed regulators and confirmed the candidate’s potential to prevent nerve cell damage after acute optic neuritis episodes.
3. Global PIONEER Registrational Program
Oculis is advancing Privosegtor through its PIONEER program, comprising three global registrational trials in optic neuritis and non-arteritic anterior ischemic optic neuropathy. The first trial, PIONEER-1 in optic neuritis, launched in Q4 2025 with site activations progressing as planned, marking the start of late-stage development.
4. Orphan Drug Status and Market Potential
Privosegtor holds Orphan Drug designation from both the EMA and FDA for optic neuritis, reflecting its focus on rare conditions with significant unmet needs. With no current neuroprotective treatments available, the potential U.S. market for optic neuropathies is estimated at $7 billion, highlighting the commercial opportunity.