Organization and Operations	12 Months Ended
Dec. 31, 2020
Organization and Operations
Organization and Operations	1. Organization and Operations The Company Catabasis Pharmaceuticals, Inc (the “Company”) is a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics. Its mission is to bring hope with life-changing therapies to patients and families that are affected by rare diseases. On October 26, 2020, the Company announced that the Phase 3 PolarisDMD trial of the Company's previous lead product candidate, edasalonexent, for the treatment of Duchenne muscular dystrophy (DMD) did not meet its primary and secondary endpoints. Based on these results, the Company announced that it was stopping activities related to the development of edasalonexent, including the Company's ongoing open-label extension trial. On January 28, 2021, the Company acquired Quellis Biosciences, Inc ("Quellis"). The Company's lead product candidate, which was acquired in the Quellis acquisition, is QLS-215, a monoclonal antibody inhibitor of plasma kallikrein in preclinical development for the treatment of hereditary angioedema, or HAE, a rare, debilitating and potentially life-threatening disease. The Company was incorporated in the State of Delaware on June 26, 2008. Liquidity The Company has entered into various sales agreements with Cowen and Company LLC, (“Cowen”), pursuant to which the Company could issue and sell shares of common stock under at-the-market offering programs (the “ATM Programs”). Shares sold pursuant to these sales agreements were sold pursuant to shelf registration statements, one of which became effective on July 19, 2016 and which was replaced by a new shelf registration statement, which became effective May 22, 2019. The Company pays Cowen 3% of the gross proceeds from any common stock sold through these sales agreements. The Company currently has $27.9 million remaining available under its sales agreement. During the year ended December 31, 2020, the Company sold an aggregate of 2,353,737 shares of common stock pursuant to the ATM Programs, at an average price of $7.13 per share, for gross proceeds of $16.8 million, resulting in net proceeds of $16.3 million after deducting sales commissions and offering expenses. On January 30, 2020, the Company entered into an underwriting agreement with Oppenheimer & Co. Inc. relating to an underwritten public offering (the “January 2020 Financing”) of 5,290,000 shares of common stock at a price to the public of $5.00 per share. This resulted in gross proceeds of $26.5 million, and net proceeds of $24.6 million. On February 6, 2019, the Company entered into an underwriting agreement with Oppenheimer & Co. Inc. relating to an underwritten public offering (the “February 2019 Financing”) of 4,000,000 shares of common stock and accompanying warrants to purchase up to 2,000,000 shares of common stock, at a combined price to the public of $5.00 per unit, for gross proceeds of $20.0 million and net proceeds of $18.5 million. The Company is subject to a number of risks similar to other life science companies, including, but not limited to, successful discovery and development of its drug candidates, raising additional capital, development by its competitors of new technological innovations, protection of proprietary technology and regulatory approval and market acceptance of the Company's products. The Company has been primarily involved with research and development activities and has incurred operating losses and negative cash flows from operations since its inception. The Company anticipates that it will continue to incur significant operating losses for the next several years as it continues to develop its product candidates. As of December 31, 2020, the Company had an accumulated deficit of $260.9 million. The Company will require substantial additional capital to fund operations. The Company has not generated any product revenues and has financed its operations primarily through public offerings and private placements of its equity securities. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenues from collaborative partners, on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company's business, results of operations, and financial condition. As of December 31, 2020, the Company had available cash, cash equivalents and short-term investments of $44.9 million. Subsequent to December 31, 2020, the Company raised gross proceeds of $110.0 million, and net proceeds of $104.0 million, through the February 2021 Financing (as described below). As part of the Quellis acquisition and the February 2021 Financing, the Company issued 86,077 shares of Series X Preferred Stock, which upon stockholder approval can be converted to 86,077,000 shares of common stock. The terms of the Series X Preferred Stock include a cash redemption feature. The redemption feature provides that, if the Company’s common stockholders fail to approve the ability of the holders of the Series X Preferred Stock to convert their respective shares into common stock by July 28, 2021, the Company could, at the holder’s option, be required to make a redemption payment to the holders of Series X Preferred Stock based on the then fair value of the Company’s common stock underlying the redeemed Series X Preferred Stock significantly in excess of current liquidity. Based on precedent transactions and the terms of the Series X Preferred Stock, the Company believes that stockholders who are entitled to vote on the conversion proposal at the Company's 2021 Annual Meeting of Stockholders, which is scheduled for June 2, 2021, will vote to approve the proposal. However, as the vote of the Company’s common stockholders is outside of the control of the Company, there is substantial doubt about its ability to continue as a going concern for at least 12 months following the issuance of these consolidated financial statements. The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

1. Organization and Operations

The Company

Catabasis Pharmaceuticals, Inc (the “Company”) is a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics. Its mission is to bring hope with life-changing therapies to patients and families that are affected by rare diseases. On October 26, 2020, the Company announced that the Phase 3 PolarisDMD trial of the Company's previous lead product candidate, edasalonexent, for the treatment of Duchenne muscular dystrophy (DMD) did not meet its primary and secondary endpoints. Based on these results, the Company announced that it was stopping activities related to the development of edasalonexent, including the Company's ongoing open-label extension trial. On January 28, 2021, the Company acquired Quellis Biosciences, Inc ("Quellis"). The Company's lead product candidate, which was acquired in the Quellis acquisition, is QLS-215, a monoclonal antibody inhibitor of plasma kallikrein in preclinical development for the treatment of hereditary angioedema, or HAE, a rare, debilitating and potentially life-threatening disease. The Company was incorporated in the State of Delaware on June 26, 2008.

Liquidity

The Company has entered into various sales agreements with Cowen and Company LLC, (“Cowen”), pursuant to which the Company could issue and sell shares of common stock under at-the-market offering programs (the “ATM Programs”). Shares sold pursuant to these sales agreements were sold pursuant to shelf registration statements, one of which became effective on July 19, 2016 and which was replaced by a new shelf registration statement, which became effective May 22, 2019. The Company pays Cowen 3% of the gross proceeds from any common stock sold through these sales agreements. The Company currently has $27.9 million remaining available under its sales agreement.

During the year ended December 31, 2020, the Company sold an aggregate of 2,353,737 shares of common stock pursuant to the ATM Programs, at an average price of $7.13 per share, for gross proceeds of $16.8 million, resulting in net proceeds of $16.3 million after deducting sales commissions and offering expenses.

On January 30, 2020, the Company entered into an underwriting agreement with Oppenheimer & Co. Inc. relating to an underwritten public offering (the “January 2020 Financing”) of 5,290,000 shares of common stock at a price to the public of $5.00 per share. This resulted in gross proceeds of $26.5 million, and net proceeds of $24.6 million.

On February 6, 2019, the Company entered into an underwriting agreement with Oppenheimer & Co. Inc. relating to an underwritten public offering (the “February 2019 Financing”) of 4,000,000 shares of common stock and accompanying warrants to purchase up to 2,000,000 shares of common stock, at a combined price to the public of $5.00 per unit, for gross proceeds of $20.0 million and net proceeds of $18.5 million.

The Company is subject to a number of risks similar to other life science companies, including, but not limited to, successful discovery and development of its drug candidates, raising additional capital, development by its competitors of new technological innovations, protection of proprietary technology and regulatory approval and market acceptance of the Company's products. The Company has been primarily involved with research and development activities and has incurred operating losses and negative cash flows from operations since its inception. The Company anticipates that it will continue to incur significant operating losses for the next several years as it continues to develop its product candidates.

As of December 31, 2020, the Company had an accumulated deficit of $260.9 million. The Company will require substantial additional capital to fund operations. The Company has not generated any product revenues and has financed its operations primarily through public offerings and private placements of its equity securities. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenues from collaborative partners, on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company's business, results of operations, and financial condition.

As of December 31, 2020, the Company had available cash, cash equivalents and short-term investments of $44.9 million. Subsequent to December 31, 2020, the Company raised gross proceeds of $110.0 million, and net proceeds of $104.0 million, through the February 2021 Financing (as described below). As part of the Quellis acquisition and the February 2021 Financing, the Company issued 86,077 shares of Series X Preferred Stock, which upon stockholder approval can be converted to 86,077,000 shares of common stock. The terms of the Series X Preferred Stock include a cash redemption feature. The redemption feature provides that, if the Company’s common stockholders fail to approve the ability of the holders of the Series X Preferred Stock to convert their respective shares into common stock by July 28, 2021, the Company could, at the holder’s option, be required to make a redemption payment to the holders of Series X Preferred Stock based on the then fair value of the Company’s common stock underlying the redeemed Series X Preferred Stock significantly in excess of current liquidity. Based on precedent transactions and the terms of the Series X Preferred Stock, the Company believes that stockholders who are entitled to vote on the conversion proposal at the Company's 2021 Annual Meeting of Stockholders, which is scheduled for June 2, 2021, will vote to approve the proposal. However, as the vote of the Company’s common stockholders is outside of the control of the Company, there is substantial doubt about its ability to continue as a going concern for at least 12 months following the issuance of these consolidated financial statements. The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.