---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-178106"
form_type: "8-K"
ticker: "ENTA"
cik: "0001177648"
company_name: "ENANTA PHARMACEUTICALS INC"
filed_at: "2022-06-22T23:59:59+00:00"
generated_at: "2026-06-24T23:52:20.365483+00:00"
event_type: "litigation"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Enanta sues Pfizer for patent infringement over Paxlovid, seeks damages only

## Summary
- Filed suit against Pfizer in U.S. District Court for Massachusetts over U.S. Patent No. 11,358,953 covering coronavirus protease inhibitors.
- Patent was awarded earlier in June 2022 based on a July 2020 application; Enanta claims Pfizer's Paxlovid infringes.
- Enanta states it will not seek an injunction or take action to block production, sale, or distribution of Paxlovid.
- Enanta seeks 'fair compensation' for Pfizer's use of the coronavirus protease inhibitor claimed in the '953 patent.

## SEC filing metadata
- accession: 0001193125-22-178106
- form_type: 8-K
- ticker: ENTA
- cik: 0001177648
- company_name: ENANTA PHARMACEUTICALS INC
- filed_at: 2022-06-22T23:59:59+00:00
- event_type: litigation
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1177648/000119312522178106/0001193125-22-178106-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1177648/000119312522178106/d356525d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-178106
- JSON: https://secwatch.observer/filing/0001193125-22-178106.json
- Plain text: https://secwatch.observer/filing/0001193125-22-178106.txt

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