Jerome Benedict Durso - 01 Dec 2025 Form 4 Insider Report for Altimmune, Inc. (ALT)

Reporting relationship: CEO-elect, Director
Issuer ticker: ALT
Reported as of: 01 Dec 2025
Net transaction value: $0
SEC form: 4
Accepted by SEC: 01 Dec 2025, 20:38:33 UTC
Prior SEC filing: 29 Sep 2025
Next SEC filing: 22 Dec 2025
Source filing: View source filing
Reporting owner signature: /s/ Gregory Weaver, as Attorney-in-Fact

Key filing fact

Jerome Benedict Durso filed Form 4 for Altimmune, Inc. (ALT) on 01 Dec 2025.

Key facts

This page summarizes Jerome Benedict Durso's Form 4 filing for Altimmune, Inc. (ALT).
2 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 01 Dec 2025, 20:38.

Change

Previous filing in this sequence was filed on 29 Sep 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001698665 Primary reporting owner

Durso Jerome Benedict

Relationship: CEO-elect, Director
Address: C/O ALTIMMUNE, INC., 910 CLOPPER ROAD, SUITE 201S, GAITHERSBURG
Signature: /s/ Gregory Weaver, as Attorney-in-Fact
Signature date: 01 Dec 2025

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ALT transaction Derivative

Stock Options (option to buy)

Award

Transaction value: $0
Shares: +1,824,400
Change %
Price: $0.000000
Shares after: 1,824,400
Date: 01 Dec 2025
Ownership: Direct
Underlying class: Common Stock, par value $0.0001
Underlying amount: 1,824,400
Exercise price: $4.93
Footnotes: F1

ALT transaction Derivative

Restricted Stock Units

Award

Transaction value: $0
Shares: +633,700
Change %
Price: $0.000000
Shares after: 633,700
Date: 01 Dec 2025
Ownership: Direct
Underlying class: Common Stock, par value $0.0001
Underlying amount: 633,700
Exercise price
Footnotes: F2, F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

The shares underlying the option become vested and exercisable over four (4) years with 25% of the shares vesting on December 1, 2026, with the remainder vesting in equal monthly installments for the following thirty-six (36) months, subject to the reporting person's continued service on each applicable vesting date.

Footnote F2

Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.0001, when vested.

Footnote F3

The RSUs become vested over four (4) years with 25% of the shares vesting December 1, 2026, with the remainder vesting in equal annual installments for the following three (3) years, subject to the reporting person's continued service through the applicable vesting date, and have no expiration date.

SEC remarks

Mr. Durso has been appointed President and Chief Executive Officer of the Company effective January 1, 2026.