Personnel-related costs, including employee payroll and related expenses, decreased by $0.6 million, from $6.0 million for the six months ended June 30, 2023 to $5.4 million for the six months ended June 30, 2024, mainly due to $0.4 million lower stock based compensation expense as there were no expense related to the equity awards that fully vested after June 30, 2023, $0.1 million reduction in outsourced services expenses and $0.1 million decrease in other personnel-related costs.
Facilities and overheads decreased by $0.4 million for the three months ended June 30, 2024 compared to the 2023 period, which is related to fewer expenses incurred on consumables and lab equipment maintenance.
Facilities and overheads increased by $0.2 million for the six months ended June 30, 2024 compared to the 2023 period, as a result of an increase in expenses related to our McConnell leased facility.
General and Administrative
General and administrative expenses were $3.4 million and $2.4 million for the three months ended June 30, 2024 and 2023, respectively. The increase of $1.1 million is primarily related to an increase of $1.0 million in stock-based compensation expenses due to stock-based awards granted during the first quarter of 2024, and $0.1 million increase in personnel, recruitment, lease and other facilities and overhead expenses.
General and administrative expenses were $6.6 million and $4.9 million for the six months ended June 30, 2024 and 2023, respectively. The increase of $1.7 million is primarily related to an increase of $1.1 million in stock-based compensation expense due to stock-based awards granted during the first quarter of 2024, an increase of $0.3 million in legal, accounting and other consulting expenses, an increase of $0.2 million in expenses related to our McConnell leased facility and an increase of $0.1 million in other facilities and overhead expenses.
Interest Income
Interest income for the three months ended June 30, 2024 and 2023 was $0.2 million and less than $0.1 million, respectively, and related to interest income on our money market fund investments.
Interest income for the six months ended June 30, 2024 and 2023 was $0.3 million and $0.1 million, respectively, and related to interest income on our money market fund investments.
Interest Expense
We recognized interest expense of $2.7 million for the three months ended June 30, 2024, related to the interest expenses and the amortization of debt discount and issuance costs for the 2023 Loan and 2024 Loan received from Innoviva in July 2023 and March 2024, respectively. Stated interest is accrued and is payable at the maturity of the 2023 Loan and the 2024 Loan in 2025.
We recognized interest expense of $4.5 million for the six months ended June 30, 2024, related to the interest expenses and the amortization of debt discount and issuance costs for the 2023 Loan and 2024 Loan received from Innoviva in July 2023 and March 2024, respectively. Stated interest is accrued and is payable at the maturity of the 2023 Loan and the 2024 Loan in 2025.
Change in Fair Value of Convertible Debt
We recognized a gain on change in the fair value of the Convertible Loan for the three months ended June 30, 2024 and 2023 of $23.4 million and $6.0 million, respectively. Such gain is primarily attributable to the decrease in our Common Stock price in the three months ended June 30, 2024, and 2023.
We recognized a loss on change in the fair value of the Convertible Loan for the six months ended June 30, 2024 and 2023 of $10.4 million and $2.9 million, respectively. Such losses are primarily attributable to the changes in our estimated probabilities of various settlement scenarios, changes in our Common Stock price, remaining loan term and