PROSPECTUS SUMMARY
The following is a summary of what we believe to be the most important aspects of our business and the offering of our securities under
this prospectus. We urge you to read this entire prospectus, including the more detailed consolidated financial statements, notes to the consolidated financial statements and other information incorporated by reference from our other filings with
the SEC or included in any applicable prospectus supplement. Investing in our securities involves risks. Therefore, carefully consider the risk factors set forth in any prospectus supplements and in our most recent annual and quarterly filings with
the SEC, as well as other information in this prospectus and any prospectus supplements and the documents incorporated by reference herein or therein, before purchasing our securities. Each of the risk factors could adversely affect our business,
operating results and financial condition, as well as adversely affect the value of an investment in our securities.
About Spero
Therapeutics, Inc.
We are a multi-asset, clinical-stage biopharmaceutical company focused on identifying, developing and
commercializing novel treatments for multi-drug resistant, or MDR, bacterial infections. Our most advanced product candidate, SPR994, is designed to be the first broad-spectrum oral carbapenem-class antibiotic for use in adults to treat MDR
Gram-negative infections. Treatment with effective orally administrable antibiotics may prevent hospitalizations for serious infections and enable earlier, more convenient and cost-effective treatment of patients after hospitalization. We also have
a platform technology known as our Potentiator Platform that we believe will enable us to develop drugs that will expand the spectrum and potency of existing antibiotics, including formerly inactive antibiotics, against Gram-negative bacteria. Our
lead product candidates generated from our Potentiator Platform are two intravenous, or IV,-administered agents, SPR741 and SPR206, designed to treat MDR Gram-negative infections in the hospital setting. In addition, we are developing SPR720, an
oral antibiotic designed for the treatment of a disease called
pulmonary non-tuberculous mycobacterial
infections, or NTM. We believe that our novel product candidates, if successfully developed and
approved, would have a meaningful patient impact and significant commercial applications for the treatment of MDR infections in both the community and hospital settings.
Additional Information
For
additional information related to our business and operations, please refer to the reports incorporated herein by reference, as described under the caption Incorporation of Documents by Reference on page 31 of this prospectus.
Our Corporate Information
We were
formed as Spero Therapeutics, LLC in December 2013 under the laws of the State of Delaware. On June 30, 2017, through a series of transactions, Spero Therapeutics, LLC merged with and into Spero Therapeutics, Inc. (formerly known as Spero OpCo,
Inc.), a Delaware corporation.
Our principal executive offices are located at 675 Massachusetts Avenue, Cambridge, Massachusetts 02139,
and our telephone number is
(857) 242-1600.
Our website address is
www.sperotherapeutics.com
. The information contained on, or that can be accessed through, our website is not part of this
prospectus. Investors should not rely on any such information in deciding whether to purchase our securities.
The mark Spero
Therapeutics is our common law trademark. All other service marks, trademarks and trade names appearing in this prospectus are the property of their respective owners. We do not intend our use or display of other companies trade names,
trademarks or service marks to imply a relationship with, or an endorsement or sponsorship of us by, these other companies. Solely for convenience, trademarks and tradenames referred to in this prospectus may appear without the
®
or
symbols, but such references are not intended to indicate in any way that we will not assert, to the fullest extent
under applicable law, our rights, or that the applicable owner will not assert its rights, to these trademarks and tradenames.