Organization and Description of Business	9 Months Ended
Sep. 30, 2019
Organization and Description of Business
Organization and Description of Business	1. Organization and Description of Business Entasis Therapeutics Holdings Inc. (“Entasis” or the “Company”) is a clinical‑stage biopharmaceutical company focused on the discovery, development and commercialization of novel antibacterial products to treat serious infections caused by multidrug-resistant Gram‑negative bacteria. The Company was initially formed as Entasis Therapeutics Limited (“Entasis Limited”) on March 6, 2015 in the United Kingdom (“U.K.”) as a wholly owned subsidiary of AstraZeneca AB (“AstraZeneca”). In connection with the spin‑out of Entasis Limited from AstraZeneca in May 2015, Entasis Limited issued 4 ordinary shares to AstraZeneca. Additionally, pursuant to a business transfer and subscription agreement with AstraZeneca (the “A Subscription Agreement”), Entasis Limited also issued 33,499,900 shares of A redeemable convertible preference shares (“A Preferred Stock”) to AstraZeneca in May 2015. In March 2016, Entasis Limited issued 25,000,000 shares of B redeemable convertible preference shares (“B Preferred Stock”) to third‑party investors. During 2018, Entasis Limited completed a corporate reorganization (the “Reorganization”). In March 2018 Entasis Limited formed Entasis Therapeutics Holdings Inc., a Delaware corporation, with nominal assets and liabilities for the purpose of consummating the Reorganization. The existing shareholders of Entasis Limited exchanged each of their classes of shares of Entasis Limited for the same number and classes of common stock and preferred stock of Entasis Therapeutics Holdings Inc. on a one‑to‑one basis. The newly issued stock of Entasis Therapeutics Holdings Inc. has substantially identical rights to the exchanged shares of Entasis Limited. As a result of the exchange, Entasis Therapeutics Holdings Inc. became the sole shareholder of Entasis Limited. Upon the completion of the Reorganization on April 23, 2018, the historical consolidated financial statements of Entasis Limited became the historical consolidated financial statements of Entasis Therapeutics Holdings Inc. On September 28, 2018, the Company completed an initial public offering of its common stock, in which the Company issued and sold 5,000,000 shares of common stock at a price to the public of $15.00 per share. The aggregate net proceeds to the Company from the initial public offering were approximately $65.6 million after deducting underwriting discounts and commissions, and offering expenses payable by the Company. Upon the completion of the Company’s initial public offering, all of the outstanding shares of redeemable convertible preferred stock of the Company, including accrued dividends, automatically converted into 8,084,414 shares of the Company’s common stock. In September 2018, the Company also effected a 1-for-20.728 reverse stock split of its issued and outstanding common stock. All of the historical share and per share information shown in these consolidated financial statements and related notes have been retroactively adjusted to give effect to the reverse stock split. Risks and Uncertainties As of September 30, 2019, the Company had $48.8 million in cash, cash equivalents and short-term investments, and an accumulated deficit of $119.9 million. Since its inception through September 30, 2019, the Company has funded its operations primarily with proceeds from the sale of redeemable convertible preferred stock and the sale of its common stock. The Company has also either directly received funding or financial commitments from, or has had its program activities conducted and funded by, United States (“U.S.”) government agencies and non-profit entities. In the absence of positive cash flows from operations, the Company is highly dependent on its ability to find additional sources of funding in the form of debt, equity financing, strategic collaborations, or partnerships. The Company believes its existing cash, cash equivalents and short-term investments, together with earned milestones from the Zai Lab partnership will enable it to fund its operating expenses and capital requirements through one year from the date of this filing. The Company is subject to a number of risks common to other life science companies, including, but not limited to, raising additional capital, development by its competitors of new technological innovations, risk of failure in preclinical and clinical studies, safety and efficacy of its product candidates in clinical trials, risk of relying on external parties such as contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”), the regulatory approval process, market acceptance of the Company’s products once approved, lack of marketing and sales history, dependence on key personnel, and protection of proprietary technology. The Company’s therapeutic programs are currently pre-commercial, spanning discovery through late development and will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization of any product candidates. These efforts require significant amounts of additional capital, adequate personnel, infrastructure, and extensive compliance-reporting capabilities. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales or achieve profitability.

1. Organization and Description of Business

Entasis Therapeutics Holdings Inc. (“Entasis” or the “Company”) is a clinical‑stage biopharmaceutical company focused on the discovery, development and commercialization of novel antibacterial products to treat serious infections caused by multidrug-resistant Gram‑negative bacteria. The Company was initially formed as Entasis Therapeutics Limited (“Entasis Limited”) on March 6, 2015 in the United Kingdom (“U.K.”) as a wholly owned subsidiary of AstraZeneca AB (“AstraZeneca”). In connection with the spin‑out of Entasis Limited from AstraZeneca in May 2015, Entasis Limited issued 4 ordinary shares to AstraZeneca. Additionally, pursuant to a business transfer and subscription agreement with AstraZeneca (the “A Subscription Agreement”), Entasis Limited also issued 33,499,900 shares of A redeemable convertible preference shares (“A Preferred Stock”) to AstraZeneca in May 2015. In March 2016, Entasis Limited issued 25,000,000 shares of B redeemable convertible preference shares (“B Preferred Stock”) to third‑party investors.

During 2018, Entasis Limited completed a corporate reorganization (the “Reorganization”). In March 2018 Entasis Limited formed Entasis Therapeutics Holdings Inc., a Delaware corporation, with nominal assets and liabilities for the purpose of consummating the Reorganization. The existing shareholders of Entasis Limited exchanged each of their classes of shares of Entasis Limited for the same number and classes of common stock and preferred stock of Entasis Therapeutics Holdings Inc. on a one‑to‑one basis. The newly issued stock of Entasis Therapeutics Holdings Inc. has substantially identical rights to the exchanged shares of Entasis Limited. As a result of the exchange, Entasis Therapeutics Holdings Inc. became the sole shareholder of Entasis Limited. Upon the completion of the Reorganization on April 23, 2018, the historical consolidated financial statements of Entasis Limited became the historical consolidated financial statements of Entasis Therapeutics Holdings Inc.

On September 28, 2018, the Company completed an initial public offering of its common stock, in which the Company issued and sold 5,000,000 shares of common stock at a price to the public of $15.00 per share. The aggregate net proceeds to the Company from the initial public offering were approximately $65.6 million after deducting underwriting discounts and commissions, and offering expenses payable by the Company. Upon the completion of the Company’s initial public offering, all of the outstanding shares of redeemable convertible preferred stock of the Company, including accrued dividends, automatically converted into 8,084,414 shares of the Company’s common stock. In September 2018, the Company also effected a 1-for-20.728 reverse stock split of its issued and outstanding common stock. All of the historical share and per share information shown in these consolidated financial statements and related notes have been retroactively adjusted to give effect to the reverse stock split.

Risks and Uncertainties

As of September 30, 2019, the Company had $48.8 million in cash, cash equivalents and short-term investments, and an accumulated deficit of $119.9 million. Since its inception through September 30, 2019, the Company has funded its operations primarily with proceeds from the sale of redeemable convertible preferred stock and the sale of its common stock. The Company has also either directly received funding or financial commitments from, or has had its program activities conducted and funded by, United States (“U.S.”) government agencies and non-profit entities. In the absence of positive cash flows from operations, the Company is highly dependent on its ability to find additional sources of funding in the form of debt, equity financing, strategic collaborations, or partnerships. The Company believes its existing cash, cash equivalents and short-term investments, together with earned milestones from the Zai Lab partnership will enable it to fund its operating expenses and capital requirements through one year from the date of this filing.

The Company is subject to a number of risks common to other life science companies, including, but not limited to, raising additional capital, development by its competitors of new technological innovations, risk of failure in preclinical and clinical studies, safety and efficacy of its product candidates in clinical trials, risk of relying on external parties such as contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”), the regulatory approval process, market acceptance of the Company’s products once approved, lack of marketing and sales history, dependence on key personnel, and protection of proprietary technology. The Company’s therapeutic programs are currently pre-commercial, spanning discovery through late development and will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization of any product candidates. These efforts require significant amounts of additional capital, adequate personnel, infrastructure, and extensive compliance-reporting capabilities. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales or achieve profitability.