Organization and Nature of Operations and Basis of Presentation

Description of Business

Synthetic Biologics, Inc. (the “Company” or “Synthetic Biologics”) is a clinical-stage biotechnology company developing pathogen-specific therapies for serious infections and diseases, with a focus on protecting the microbiome. The Company is developing an oral biologic to protect the gastrointestinal (GI) microflora from the effects of intravenous (IV) antibiotics for the prevention of C. difficile infection, an oral treatment to reduce the impact of methane producing organisms on constipation-predominant irritable bowel syndrome (C-IBS) and a monoclonal antibody combination for the treatment of Pertussis. In addition, the Company is developing a Phase 2 oral estriol drug for the treatment of relapsing-remitting multiple sclerosis (MS) and cognitive dysfunction in MS.

Therapeutic Area	Product Candidate	Status

Relapsing-remitting MS	Trimesta (oral estriol)	Patient follow-up is complete in the Phase 2 trial and the lead principal investigator from University of California, Los Angeles (UCLA) presented additional Phase 2 clinical outcome data, including more detailed results on improvements in cognitive and disability measures at the ACTRIMS-ECTRIMS Joint Meeting in September 2014

Cognitive dysfunction in MS	Trimesta (oral estriol)	Patient enrollment underway in Phase 2 clinical trial

C. difficile infection prevention	SYN-004 (oral enzyme)	Intend to initiate Phase 1a and 1b SYN-004 clinical trials during 4^th quarter 2014

Constipation-predominant irritable bowel syndrome (C-IBS)	SYN-010 (oral compound)	Intend to initiate Phase 2 clinical trial during 1st half of 2015; Collaboration with Cedars-Sinai Medical Center

Pertussis	SYN-005 (monoclonal antibodies)	Positive preclinical research findings reported in 2014; Collaborations with Intrexon and The University of Texas at Austin

Acinetobacter infection	SYN-001 (monoclonal antibody)	Discovery stage; Collaboration with Intrexon

IBS	SYN-007 (biologic)	Discovery stage; We are still evaluating an IP option; Collaboration with Intrexon

Basis of Presentation

The accompanying consolidated financial statements have been prepared pursuant to the rules and regulations of Securities and Exchange Commission (“SEC”) for interim financial information. Accordingly, they do not include all of the information and notes required by U.S. Generally Accepted Accounting Principles (“GAAP”) for complete financial statements. The accompanying consolidated financial statements include all adjustments, comprised of normal recurring adjustments, considered necessary by management to fairly state our results of operations, financial position and cash flows. The operating results for the interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. These consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2013 (“2013 Form 10-K”) as filed with the SEC. The interim results for the three and nine months ended September 30, 2014, are not necessarily indicative of results for the full year.

The consolidated financial statements are prepared in conformity with U.S. GAAP, which requires the use of estimates, judgments and assumptions that affect the amounts of assets and liabilities at the reporting date and the amounts of revenue and expenses in the periods presented. We believe that the accounting estimates employed are appropriate and the resulting balances are reasonable; however, due to the inherent uncertainties in making estimates actual results could differ from the original estimates, requiring adjustments to these balances in future periods.

Change in Filing Status

On June 30, 2014, the Company exceeded the $75.0 million public float threshold to trigger accelerated filer status with the SEC. Consequently the Company will no longer be a Smaller Reporting Company (SRC) and the Company’s auditors must provide an auditor attestation on our internal controls to be included in the Company’s Form 10-K for the year ending December 31, 2014. Such Form 10-K will continue to provide scaled SRC-level disclosures; the larger reporting company disclosures will commence in the Company’s Form 10-Q for the three months ended March 31, 2015.