Cost of goods sold and gross margin
Cost of goods sold increased $0.7 million, or 32%, to $2.8 million for the six months ended June 30, 2023, compared to the six months ended June 30, 2022. This increase was primarily due to higher sales of Barostim.
Gross profit was $14.6 million for the six months ended June 30, 2023, an increase of $7.7 million, or 110%, over the six months ended June 30, 2022. Gross margin increased to 84% for the six months ended June 30, 2023, compared to 76% for the six months ended June 30, 2022. This increase was due primarily to a decrease in the cost per unit driven by an increase in the production volume.
Research and development expenses
R&D expenses increased $2.1 million, or 45%, to $6.7 million for the six months ended June 30, 2023, compared to the six months ended June 30, 2022. This change was driven by a $1.1 million increase in compensation expenses as a result of increased headcount, a $0.5 million increase in non-cash stock-based compensation expense and a $0.5 million increase in consulting fees.
Selling, general and administrative expenses
SG&A expenses increased $8.6 million, or 37%, to $31.9 million for the six months ended June 30, 2023, compared to the six months ended June 30, 2022. This change was primarily driven by a $5.0 million increase in compensation expenses, mainly as a result of increased headcount, a $1.3 million increase in marketing and advertising expenses associated with the commercialization of Barostim in the U.S, a $1.2 million increase in travel expenses, and a $0.8 million increase in non-cash stock-based compensation expense.
Interest expense
Interest expense increased $0.7 million for the six months ended June 30, 2023, compared to the six months ended June 30, 2022. This increase was driven by the interest expense on borrowings under the Loan Agreement entered into on October 31, 2022.
Other income (expense), net
Other income, net was $1.7 million for the six months ended June 30, 2023, compared to other expense, net of $0.1 million for the six months ended June 30, 2022. The income for the six months ended June 30, 2023 was primarily driven by interest income on our interest-bearing accounts.
Provision for income taxes
Provision for income taxes was nominal for each of the six months ended June 30, 2023 and June 30, 2022.
Liquidity, capital resources and plan of operations
We have incurred significant operating losses and negative cash flows from operations since our inception, and we anticipate that we will incur significant losses for at least the next several years. As of June 30, 2023 and December 31, 2022, we had cash and cash equivalents of $90.8 million and $106.2 million, respectively. For the three months ended June 30, 2023 and 2022, our net losses were $11.7 million and $11.1 million, respectively. For the six months ended June 30, 2023 and 2022, our net losses were $23.0 million and $21.1 million, respectively. Our net cash used in operating activities for the six months ended June 30, 2023 and 2022 was $23.1 million and $20.7 million, respectively.