---
schema_version: "secwatch.filing_event.v1"
accession: "0001070081-25-000014"
form_type: "8-K"
ticker: "PTCT"
cik: "0001070081"
company_name: "PTC THERAPEUTICS, INC."
filed_at: "2025-05-05T23:59:59+00:00"
generated_at: "2026-05-22T16:18:09.712469+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# PTC518 Phase 2 PIVOT-HD meets primary endpoint with dose-dependent HTT lowering at Week 12

## Summary
- Primary endpoint met: dose-dependent blood HTT protein reduction (p<0.0001) at Week 12.
- 5mg dose lowered HTT 23% in Stage 2/3; 10mg lowered 39% (Stage 2) and 36% (Stage 3).
- Favorable dose-dependent trends on cUHDRS, TFC, SDMT in Stage 2 patients at 12 and 24 months.
- No treatment-related SAEs or NfL spikes; safety and tolerability profile favorable.
- At Month 24, dose-dependent NfL lowering: -8.9% (5mg, p=0.12) and -14% (10mg, p=0.03) vs natural history.

## SEC filing metadata
- accession: 0001070081-25-000014
- form_type: 8-K
- ticker: PTCT
- cik: 0001070081
- company_name: PTC THERAPEUTICS, INC.
- filed_at: 2025-05-05T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1070081/000107008125000014/0001070081-25-000014-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1070081/000107008125000014/tmb-20250505x8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001070081-25-000014
- JSON: https://secwatch.observer/filing/0001070081-25-000014.json
- Plain text: https://secwatch.observer/filing/0001070081-25-000014.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.