Spero Therapeutics to Provide Business Update and Report Fourth Quarter and Full Year 2023 Financial Results on Wednesday, March 13, 2024

Spero Therapeutics, Inc. (Nasdaq: SPRO), a multi-asset clinical-stage biopharmaceutical company, focused on identifying and developing treatments in high unmet need areas involving rare diseases and multi-drug resistant (MDR) bacterial infections, today announced that it will host a conference call and live audio webcast on Wednesday, March 13, 2024 at 4:30 p.m. ET to report its fourth quarter and full year financial results and provide an update on its business and pipeline.

To access the call, please dial 1-877-704-4453 (domestic) or 1-201-389-0920 (international) and refer to conference ID 13744458, or click on this Link and request a return call. The audio webcast can be accessed on the "Events and Presentations" page under the “Connect” tab of the Company's website at www.sperotherapeutics.com. The archived webcast will also be available on Spero's website for 30 days following the call.

About Spero TherapeuticsSpero Therapeutics, headquartered in Cambridge, Massachusetts, is a multi-asset, clinical-stage biopharmaceutical company focused on identifying, developing, novel therapies for rare diseases and multi-drug resistant (MDR) bacterial infections with high unmet need.

• Spero Therapeutics is developing SPR720 as a novel oral therapy candidate for the treatment of a rare, orphan pulmonary disease caused by non-tuberculous mycobacterial infections.
• Tebipenem HBr is an investigational drug in the United States being developed for the treatment of complicated urinary tract infection (cUTI), including pyelonephritis, caused by certain bacteria, in adult patients who have limited treatment options; tebipenem HBr is not U.S. Food and Drug Administration (FDA)-approved.
• Spero Therapeutics also has an IV-administered next generation polymyxin product candidate, SPR206, developed from its potentiator platform, which is in development to treat MDR Gram-negative infections in the hospital setting.

For more information, visit https://sperotherapeutics.com.

Investor Relations Contact: Ted JenkinsVice President, Investor Relations and Strategic [e-mail] [phone]

Media Inquiries: Lora Grassilli, Health Media RelationsZeno [e-mail]646-932-3735