Employee Retention Credit. Employee retention credit income was $0.2 million for the nine months ended March 31, 2022. This amount is a result of the benefits we qualified for under the Coronavirus Aid, Relief, and Economic Security Act during the nine months ended March 31, 2022. We did not recognize any income for employee retention credits for the nine months ended March 31, 2021.
Income Taxes. For the nine months ended March 31, 2022 and 2021 we did not recognize any income tax benefit due to our net losses, and our determination that a valuation allowance was required for all of our deferred tax assets.
Liquidity and Capital Resources
We have incurred cumulative net losses of $199.8 million since our inception, and as a clinical stage company we have not generated any revenue to date. For the nine months ended March 31, 2022, we incurred a net loss of $31.6 million and we used $27.5 million of cash in our operating activities. As of March 31, 2022, our unrestricted cash and cash equivalents balance was $63.4 million and working capital was approximately $61.5 million. Presented below is a summary of the key events affecting our liquidity and capital resources for the nine months ended March 31, 2022, and the expected impact of financing activities completed in April and May 2022.
In October and November 2021, we completed an underwritten offering that resulted in net proceeds of $47.3 million (the “2021 Underwritten Offering”) and a registered direct offering that resulted in net proceeds of $5.0 million (the “2021 RDO”), for total net proceeds of approximately $52.3 million.
In December 2020, we entered into an Equity Distribution Agreement (the “EDA”) with Oppenheimer & Co. Inc. as sales agent that provided for an “at the market offering” for the sale of up to $50.0 million in shares of our common stock (the “Placement Shares”). For the nine months ended March 31, 2022, we sold 138,388 Placement Shares for which aggregate net proceeds of approximately $1.5 million were received. We provided notice of termination of the EDA to Oppenheimer & Co. Inc. in May 2022 and no further equity securities are issuable under the agreement. Accordingly, the EDA is no longer a potential source of liquidity. For additional information about the EDA, please refer to Note 6 to the financial statements included in Part I, Item 1 of this Report.
In August 2021, we entered into a purchase agreement (the “Purchase Agreement”) with Lincoln Park Capital Fund, LLC (“LPC”), which provides that we may sell to LPC up to an aggregate of $20.0 million of shares of our common stock (the “Purchase Shares”). The aggregate number of shares that we can sell to LPC under the Purchase Agreement was 1,669,620 shares of common stock. For the nine months ended March 31, 2022, LPC purchased 115,708 Purchase Shares and we received net proceeds of $1.2 million. We provided notice of termination of the Purchase Agreement to LPC in May 2022 and no further equity securities are issuable under the agreement. Accordingly, the Purchase Agreement is no longer a potential source of liquidity. For additional information about the Purchase Agreement, please refer to Note 6 to the financial statements included in Part I, Item 1 of this Report.
In April 2021, we entered into a $30.0 million Loan and Security Agreement (the “Loan Agreement”) with SLR Investment Corp. and certain other lenders (the “Lenders”). The Lenders agreed to loan up to $30.0 million in three tranches consisting of (i) a $15.0 million term A loan that was funded on April 14, 2021, (ii) term B and term C loans for an aggregate of $15.0 million that were subject to our ability to obtain prescribed amounts of financing and the achievement of certain clinical. We did not achieve the initial clinical milestones by January 2022 and accordingly, term B and term C loans are no longer a potential source of liquidity.
The term A loan has a maturity date of April 1, 2026. Outstanding borrowings under the term A loan bear interest at a floating rate equal to (a) 8.75% per annum plus (b) the greater of (i) the rate per annum published by the Intercontinental Exchange Benchmark Administration Ltd. (“IEBA”) for a term of one month and (ii) 0.12% per annum. For the period from April 14, 2021 through December 31, 2021, the IEBA rate for a term of one month was approximately 0.12% per annum. As of March 31, 2022, the IEBA rate for a term of one month was approximately 0.23% per annum. Therefore, the contractual rate was 8.98% as of March 31, 2022 and 8.87% as of June 30, 2021. We are permitted to make interest-only payments on the term A loan at least through May 1, 2023.
As a condition of the Loan Agreement, our cash and cash equivalents became subject to a blocked account control agreement (“BACA”) in favor of the Lenders whereby a cash balance of at least $5.0 million was required beginning on December 31, 2021. In the event of a default under the Loan Agreement, the BACA would enable the Lenders to prevent the release of funds from our cash accounts until the default is cured or waived. For additional information about the Loan Agreement, please refer to Note 5 to the financial statements included in Part I, Item 1 of this Report.