---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-25-113379"
form_type: "8-K"
ticker: "ALKS"
cik: "0001520262"
company_name: "Alkermes plc."
filed_at: "2025-09-08T23:59:59+00:00"
generated_at: "2026-05-17T07:34:08.656992+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Alkermes' alixorexton meets primary endpoint in phase 2 NT1 study; all doses improve wakefulness

## Summary
- Primary endpoint: MWT mean sleep latency improved by 22.2-26.0 min vs placebo -0.6 min (p<0.01 all doses).
- ESS score normalized (-6.4 to -8.7 vs placebo -3.1, p<0.01); cataplexy rate reduced (6mg p=0.01).
- >40% of 6mg/8mg patients had 100% cataplexy reduction at week 6; improvements in fatigue/cognition.
- No serious TEAEs; common mild-moderate events: pollakiuria, insomnia, salivary hypersecretion, blurred vision.
- Global phase 3 program for alixorexton in NT1 to begin Q1 2026.

## SEC filing metadata
- accession: 0000950170-25-113379
- form_type: 8-K
- ticker: ALKS
- cik: 0001520262
- company_name: Alkermes plc.
- filed_at: 2025-09-08T23:59:59+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/1520262/000095017025113379/0000950170-25-113379-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1520262/000095017025113379/alks-20250908.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-25-113379
- JSON: https://secwatch.observer/filing/0000950170-25-113379.json
- Plain text: https://secwatch.observer/filing/0000950170-25-113379.txt

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