The Company	3 Months Ended
Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
The Company	1. The Company Clearside Biomedical, Inc. (the “Company”) is a biopharmaceutical company dedicated to developing and delivering treatments that restore and preserve vision for people with serious back of the eye diseases. The Company’s proprietary SCS Microinjector targets the suprachoroidal space and offers unique access to the macula, retina and choroid where sight-threatening disease often occurs. This suprachoroidal space injection is an inherently flexible, in-office, non-surgical procedure, intended to provide targeted delivery to the site of disease and to work with both established and new formulations of medications, as well as future therapeutic innovations. Incorporated in the State of Delaware on May 26, 2011, the Company has its corporate headquarters in Alpharetta, Georgia. The Company’s activities since inception have primarily consisted of developing product and technology rights, raising capital and performing research and development activities. The Company has no current source of revenue to sustain present activities, and does not expect to generate meaningful revenue until and unless the Company receives regulatory approval of and successfully commercializes its product candidates, either on its own or with a third party. The Company is subject to a number of risks and uncertainties similar to those of other life science companies at a similar stage of development, including, among others, the need to obtain adequate additional financing, successful development efforts including regulatory approval of products, compliance with government regulations, successful commercialization of potential products, protection of proprietary technology and dependence on key individuals. Liquidity The Company had cash and cash equivalents of $26.1 million as of March 31, 2021. On January 6, 2021, the Company entered into a securities purchase agreement with certain institutional purchasers that purchased 4.2 million shares of its common stock in a registered direct offering at a price of $2.851 per share. The Company raised net proceeds of $11.1 million after deducting offering expenses. In addition, during the three months ended March 31, 2021, the Company sold 1.2 million shares of its common stock for net proceeds of $3.2 million under its at-the-market agreement with Cowen and Company, LLC. The Company has funded its operations primarily through the sale of common stock and convertible preferred stock and the issuance of long-term debt. The Company will continue to need to obtain additional financing to fund future operations, including completing the development, partnering and potential commercialization of its primary product candidates. The Company will need to obtain financing to conduct additional trials for the regulatory approval of its product candidates if requested by regulatory bodies, and completing the development of any product candidates that might be acquired. If such products were to receive regulatory approval, the Company would need to obtain financing to prepare for the potential commercialization of its product candidates, if the Company decides to commercialize the products on its own. The Company has suffered recurring losses and negative cash flows from operations since inception and anticipates incurring additional losses until such time, if ever, that it can obtain regulatory approval to sell, and then generate significant revenue from commercializing its lead product candidate, XIPERE™ (triamcinolone acetonide suprachoroidal injectable suspension) with its licensees. In the absence of product or other revenues, the amount, timing, nature or source of which cannot be predicted, the Company’s losses will continue as it conducts its research and development activities. These conditions raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the financial statements are issued. Based on its current plans and forecasted expenses, the Company expects that its cash and cash equivalents as of the filing date, May 17, 2021, will enable it to fund its planned operating expenses and capital expenditure requirements into the first quarter of 2022. This estimate does not give effect to additional development milestone payments the Company might receive under the agreements with Bausch, REGENXBIO or Arctic Vision, or in connection with any other potential license or collaboration agreement for XIPERE or any future product candidates. The Company has based this estimate on assumptions that may prove to be wrong, and it could exhaust its capital resources sooner than expected. Until the Company can generate sufficient revenue, the Company will need to finance future cash needs through public or private equity offerings, license agreements, debt financings or restructurings, collaborations, strategic alliances and marketing or distribution arrangements. The Company’s financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result should the Company be unable to continue as a going concern.

The Company

3 Months Ended

Mar. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. The Company

Clearside Biomedical, Inc. (the “Company”) is a biopharmaceutical company dedicated to developing and delivering treatments that restore and preserve vision for people with serious back of the eye diseases. The Company’s proprietary SCS Microinjector targets the suprachoroidal space and offers unique access to the macula, retina and choroid where sight-threatening disease often occurs. This suprachoroidal space injection is an inherently flexible, in-office, non-surgical procedure, intended to provide targeted delivery to the site of disease and to work with both established and new formulations of medications, as well as future therapeutic innovations. Incorporated in the State of Delaware on May 26, 2011, the Company has its corporate headquarters in Alpharetta, Georgia.

The Company’s activities since inception have primarily consisted of developing product and technology rights, raising capital and performing research and development activities. The Company has no current source of revenue to sustain present activities, and does not expect to generate meaningful revenue until and unless the Company receives regulatory approval of and successfully commercializes its product candidates, either on its own or with a third party. The Company is subject to a number of risks and uncertainties similar to those of other life science companies at a similar stage of development, including, among others, the need to obtain adequate additional financing, successful development efforts including regulatory approval of products, compliance with government regulations, successful commercialization of potential products, protection of proprietary technology and dependence on key individuals.

Liquidity

The Company had cash and cash equivalents of $26.1 million as of March 31, 2021. On January 6, 2021, the Company entered into a securities purchase agreement with certain institutional purchasers that purchased 4.2 million shares of its common stock in a registered direct offering at a price of $2.851 per share. The Company raised net proceeds of $11.1 million after deducting offering expenses. In addition, during the three months ended March 31, 2021, the Company sold 1.2 million shares of its common stock for net proceeds of $3.2 million under its at-the-market agreement with Cowen and Company, LLC.

The Company has funded its operations primarily through the sale of common stock and convertible preferred stock and the issuance of long-term debt. The Company will continue to need to obtain additional financing to fund future operations, including completing the development, partnering and potential commercialization of its primary product candidates. The Company will need to obtain financing to conduct additional trials for the regulatory approval of its product candidates if requested by regulatory bodies, and completing the development of any product candidates that might be acquired. If such products were to receive regulatory approval, the Company would need to obtain financing to prepare for the potential commercialization of its product candidates, if the Company decides to commercialize the products on its own.

The Company has suffered recurring losses and negative cash flows from operations since inception and anticipates incurring additional losses until such time, if ever, that it can obtain regulatory approval to sell, and then generate significant revenue from commercializing its lead product candidate, XIPERE™ (triamcinolone acetonide suprachoroidal injectable suspension) with its licensees. In the absence of product or other revenues, the amount, timing, nature or source of which cannot be predicted, the Company’s losses will continue as it conducts its research and development activities.

These conditions raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the financial statements are issued. Based on its current plans and forecasted expenses, the Company expects that its cash and cash equivalents as of the filing date, May 17, 2021, will enable it to fund its planned operating expenses and capital expenditure requirements into the first quarter of 2022. This estimate does not give effect to additional development milestone payments the Company might receive under the agreements with Bausch, REGENXBIO or Arctic Vision, or in connection with any other potential license or collaboration agreement for XIPERE or any future product candidates. The Company has based this estimate on assumptions that may prove to be wrong, and it could exhaust its capital resources sooner than expected. Until the Company can generate sufficient revenue, the Company will need to finance future cash needs through public or private equity offerings, license agreements, debt financings or restructurings, collaborations, strategic alliances and marketing or distribution arrangements.

The Company’s financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result should the Company be unable to continue as a going concern.