COVID-19 vaccines, and compliance with vaccine mandates. Future developments in these and other areas present material uncertainty and risk with respect to our clinical trials, business, financial condition and results of operations.
There is substantial doubt about our ability to continue as a going concern, which may affect our ability to obtain future financing and may require us to curtail our operations. We will need to raise additional capital to support our operations.
The unaudited condensed financial statements and accompanying notes thereto included disclosures that our recurring losses and negative cash flows from operations raise substantial doubt about our ability to continue as a going concern. Our financial statements as of June 30, 2022 and December 31, 2021 were prepared under the assumption that we will continue as a going concern and do not include any adjustments that might result from the outcome of this uncertainty. As of June 30, 2022, we had unrestricted cash and cash equivalents of $37.0 million, and we have had recurring losses from operations and negative operating cash flows since inception.
We will need to raise additional capital to support our operations and product development activities. In the near term, we expect to continue to fund our operations, if at all, primarily through equity and debt financings. Our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions, including the current recession, and the recent disruptions to, and volatility in, financial markets in the United States and worldwide resulting from the ongoing COVID-19 pandemic. We may also seek funds through arrangements with collaborators, grant agencies or others that may require us to relinquish rights to the product candidates that we might otherwise seek to develop or commercialize independently. If we are unable to secure additional funds when needed or on acceptable terms, we may be required to defer, reduce or eliminate significant planned expenditures, restructure, curtail or eliminate some or all of our development programs or other operations, dispose of technology or assets, pursue an acquisition of our company by a third party at a price that may result in a loss on investment for our stockholders, enter into arrangements that may require us to relinquish rights to certain of our product candidates, technologies or potential markets, file for bankruptcy or cease operations altogether. Any of these events could have a material adverse effect on our business, financial condition and results of operations.
On March 27, 2020, we completed a private placement (“2020 Private Placement”) transaction in which we sold to Innoviva a total of 8,710,800 newly issued shares of the Company’s common stock and warrants to purchase 8,710,800 shares of common stock, with an exercise price per share of $2.87. The 2020 Private Placement was closed in two tranches for total aggregate gross proceeds of $25.0 million.
During 2021, we entered into a securities purchase agreement in connection with certain private placements. See Note 2 to condensed consolidated financial statements contained in this report for a description of the 2021 private placements.
On October 28, 2021, we completed a private placement (the “October 2021 Private Placement”) transaction in which we sold to CFF and Innoviva Strategic Opportunities LLC, a total of 2,121,213 shares of our newly issued shares of common stock, par value $0.01 per share, for aggregate gross proceeds of approximately $7.0 million, before deducting transaction expenses.
On February 9, 2022, we entered into a securities purchase agreement to sell our common stock and warrants to Innoviva (“February 2022 Private Placement”). Pursuant and subject to the terms and conditions of the securities purchase agreement and related agreements, Innoviva agreed to purchase 9,000,000 newly issued shares of our common stock, at a price of $5.00 per share, and warrants to purchase up to 4,500,000 additional shares of our common stock, with an exercise price of $5.00 per share. The stock purchases occurred in two tranches. On February 9, 2022, Innoviva purchased 3,614,792 shares of common stock and warrants to purchase 1,807,396 shares of common stock for an aggregate purchase price of approximately $18.1 million. On March 31, 2022, upon our stockholders voting in favor of the transaction, Innoviva purchased 5,385,208 shares of common stock and warrants to purchase 2,692,604 shares of common stock for an aggregate purchase price of $26.9 million.
While we believe that our existing resources and expected proceeds from the second tranche of the February 2022 Private Placement will be sufficient to fund our planned operations into the first quarter of 2023, we cannot provide