General and Administrative Expenses
General and administrative expenses increased by $6.6 million to $25.0 million for the nine months ended September 30, 2024 from $18.4 million for the nine months ended September 30, 2023, an increase of 36%. The increase in general and administrative expenses was attributable to a $5.2 million increase in employee expenses primarily due to a $3.1 million increase in employee stock-based compensation expenses and additional costs related to company growth, a $1.0 million increase in professional services due to increased legal fees and consulting expenses, and a $0.4 million increase in other costs, including general office, facilities, and insurance expenses.
Other Income, Net
Other income, net increased by $6.0 million to $13.3 million for the nine months ended September 30, 2024 from $7.3 million for the nine months ended September 30, 2023. The increase was primarily attributable to an increase in interest and investment income due to an increase in interest-earning assets from the proceeds of financing activities.
Liquidity and Capital Resources
From our inception through September 30, 2024, we raised an aggregate of $839.2 million through equity financings including private placements of preferred stock before we became a public company, our private placement of preferred stock in February 2021 and registered offerings of our common stock, including our at-the-market offering programs.
As of September 30, 2024, we had $344.3 million in cash, cash equivalents and short-term investments which we expect will enable us to fund our operating expenses and capital expenditure requirements into mid-2027, including all navenibart program activities through the completion of a planned Phase 3 pivotal trial, as well as advancing our STAR-0310 OX40 program through submission of an IND and early proof-of-concept results from a Phase 1a trial. We have based this estimate on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Furthermore, our operating plan may change as a result of many factors currently unknown to us, and we may need to seek additional financing to fund our long-term operations sooner than planned.
Advancing the development of navenibart, STAR-0310, or any future product candidates will require a significant amount of capital and our existing cash, cash equivalents and short-term investments will not be sufficient to enable us to fund the completion of development of any of our product candidates, including navenibart, STAR-0310 or any future product candidate. In addition, navenibart, STAR-0310, or any future product candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of product candidates that we do not expect to be commercially available for years, if at all. Accordingly, we will need to obtain substantial additional funding to complete the development and commercialization of navenibart, STAR-0310 or any future product candidates, support our continuing operations, future clinical trials and the expansion of our pipeline. Adequate additional financing may not be available to us on acceptable terms, or at all. The terms of any financing may adversely affect the holdings or the rights of our stockholders. General economic conditions, both inside and outside the United States, including heightened inflation, capital market instability and volatility, interest rate and currency rate fluctuations and economic slowdown or recession as well as pandemics, epidemics and geopolitical events, including civil or political unrest (such as the Ukraine-Russian war and the conflict in the Middle East), may have a significant impact on the availability of funding sources and the terms on which any funding may be available. In addition, market instability and volatility, high levels of inflation and interest rate fluctuations may increase our cost of financing or restrict our access to potential sources of future liquidity. If we fail to raise capital as, and when, needed, we may be unable to continue our operations at planned levels and be forced to modify our business strategies and reduce or terminate our operations. Although we will continue to pursue these plans, there is no assurance that we will be successful in obtaining sufficient funding on terms acceptable to us to fund continuing operations when needed or at all.
October 2023 Financing
On October 16, 2023, we closed the October 2023 Financing, in which we sold (i) 8,253,895 shares of our common stock and accompanying common stock warrants to purchase an aggregate of 6,190,418 shares of common stock and (ii), in lieu of common stock to certain investors, pre-funded warrants to purchase up to an aggregate of 1,571,093 shares of common stock and accompanying common stock warrants to purchase up to an aggregate of 1,178,320 shares of common stock for aggregate gross proceeds of $64.0 million and net proceeds of $59.5 million.