---
schema_version: "secwatch.filing_event.v1"
accession: "0001140361-26-038529"
form_type: "8-K"
ticker: "INSM"
cik: "0001104506"
company_name: "INSMED Inc"
filed_at: "2026-10-05T11:01:19+00:00"
generated_at: "2026-10-12T14:43:55.802522+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Insmed CFO Sara Bonstein to step down October 30; company reaffirms full-year 2026 guidance

## Summary
- CFO Sara Bonstein will separate from Insmed effective October 30, 2026, and will stay through the Q3 2026 results and the October 29 earnings call.
- Insmed said the transition is not related to any disagreement on accounting practices, financial statements, internal controls or operations.
- Insmed reaffirmed 2026 guidance: BRINSUPRI revenue of $1.25B-$1.40B and ARIKAYCE revenue of $450M-$470M.
- CEO Will Lewis said Insmed raised more than $4.2 billion in capital during Bonstein's nearly seven years as CFO; a search firm is aiding the successor search.
- Q3 2026 financial results will be released October 29, 2026, with a conference call at 8:00 a.m. ET.

## SEC filing metadata
- accession: 0001140361-26-038529
- form_type: 8-K
- ticker: INSM
- cik: 0001104506
- company_name: INSMED Inc
- filed_at: 2026-10-05T11:01:19+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 5.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1104506/000114036126038529/0001140361-26-038529-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1104506/000114036126038529/ef20083216_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001140361-26-038529
- JSON: https://secwatch.observer/filing/0001140361-26-038529.json
- Plain text: https://secwatch.observer/filing/0001140361-26-038529.txt

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