Altimmune Inc. (NASDAQ:ALT) Q4 2022 Earnings Conference Call February 28, 2023 8:30 AM ET Company Participants Vipin Garg - President, Chief Executive Officer Richard Eisenstadt - Chief Financial Officer Scott Harris - Chief Medical Officer Scot Roberts - Chief Scientific Officer Conference Call Participants Seamus Fernandez - Guggenheim Securities Yasmeen Rahimi - Piper Sandler Roger Song - Jefferies Corrine Jenkins - Goldman Sachs Mayank Mamtani - B. Riley Jon Wolleben - JMP Securities Joe Pantginis - HC ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-32587 ALTIMMUNE, INC. (Exact name of registrant as specified in its charter) Identification No.) (I.R.S.Employer T ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-32587 ALTIMMUNE, INC. (Exact Name of Registrant as Specified in its Charter) Delaware 20-2726770 (State or Other Jurisdictio ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common stock, par value $0.0001 per share ALT The NASDAQ Global Market FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commi ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common stock, par value $0.0001 per share ALT The NASDAQ Global Market FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Comm ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ALTIMMUNE, INC. (Exact name of registrant as specified in its charter) FORM 10-K (Mark One) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2019 ☐ Transition Report under Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number: 001-32587 Delaware 20-2726770 (State or other jurisdiction of incorporatio ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common stock, par value $0.0001 per share ALT The NASDAQ Global Market FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2019 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common stock, par value $0.0001 per share ALT The NASDAQ Global Market FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2019 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commi ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-32587 Altimmune, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 20-2726770 State or Other Jurisdiction of ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2018 ☐ Transition Report under Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number: 001-32587 ALTIMMUNE, INC. (Exact name of registrant as specified in its charter) Delaware 20-2726770 (State or other jurisdiction of incorporatio ...