Glenn A. Eisenberg
Executive Vice President and Chief Financial Officer at Laboratory Co. of America
Thank you, Adam. I'm going to start my comments with a review of our second quarter results, followed by a discussion of our performance in each segment and conclude with an update on our full year guidance. For reference, we've also included additional business information that can be found in our supplemental deck on our Investor Relations website.
Revenue for the quarter was $3.2 billion, an increase of 6.2% compared to last year, primarily due to organic base business growth and the impact from acquisitions, partially offset by lower COVID testing and foreign exchange. The base business grew 6.9% compared to the base business last year, driven primarily by organic growth of 4.5%. Operating income for the quarter was $295 million or 9.2% of revenue or 14.9% on an adjusted basis.
During the quarter, we had $100 million of restructuring charges and special items, primarily related to acquisitions and LaunchPad initiatives. In addition, we had $23 million of expense for the transition service agreements related to the spin-off Fortrea with the corresponding income recorded in other income. Excluding these items and amortization of $62 million, adjusted operating income in the quarter was $480 million or 14.9% of revenue, compared to $448 million or 14.8% last year. The increase in operating income and margin was due to the benefit of demand and LaunchPad savings that were partially offset by higher personnel expenses.
Our LaunchPad initiative continues to be on track to deliver $100 million to $125 million of savings this year, consistent with our long-term target. The adjusted tax rate for the quarter was 23% compared to 23.9% last year. The lower adjusted tax rate was primarily due to the geographic mix of earnings and additional R&D tax credits. We continue to expect the full year adjusted tax rate to be approximately 23%.
Net earnings from continuing operations for the quarter were $206 million or $2.43 per diluted share. Adjusted EPS were $3.94 in the quarter, up 15% from last year. Operating cash flow from continuing operations was $561 million in the quarter compared to $162 million a year ago. The increase in cash flow was due to cash earnings and working capital. Capital expenditures totaled $128 million in the quarter or 4% of revenue. This compares to $103 million or 3.4% in the prior year. For the full year, we continue to expect capital expenditures to be approximately 3.5% of revenue. Free cash flow from continuing operations for the quarter was $433 million.
During the quarter, the company invested $34 million in acquisitions, paid out $60 million in dividends and repurchased $100 million of stock. The Board of Directors has approved an increase in its share repurchase authorization by $1 billion to a total of $1.4 billion. At quarter end, we had $265 million in cash, while debt was $5.1 billion. Our leverage was 2.4 times gross debt to trailing 12 months adjusted EBITDA. We have $2 billion of debt maturing over the next 12 months, and we expect to refinance it later this year.
Now I'll review our segment performance, beginning with Diagnostics Laboratories. Revenue for the quarter was $2.5 billion, an increase of 7.9% compared to last year, with organic growth of 4.7% and acquisitions net of divestitures contributing 3.2%, partially offset by foreign currency translation of 0.1%. The base business grew 8.9% compared to the base business last year, driven primarily by organic growth of 5.7%. Total volume increased 5.7% compared to last year. Base Business volume grew 6.3% compared to the Base Business last year as organic volume increased 3.5% while acquisitions contributed 2.9%.
Price mix increased 2.1% versus last year due to an organic base business increase that was partially offset by lower COVID testing. Base Business organic price/mix was up 2.2% compared to the Base Business last year. Diagnostics adjusted operating income for the quarter was $442 million or 17.5% of revenue, compared to $410 million or 17.5% last year. Adjusted operating income was up due to organic demand, acquisitions and LaunchPad savings, partially offset by higher personnel costs.
Operating margins were flat but would have been up approximately 20 basis points, were it not for the impact of a cyber event that affected a large partner.
Now I'll review the segment performance in Biopharma Laboratory Services. Revenue for the quarter was $707 million, an increase of 1.1% compared to last year due to an increase in organic revenue of 1.2%, partially offset by foreign currency translation of 0.1%. The revenue growth was driven by continued strength in Central Labs, which was up 9%, while early development was down 15% due to the higher than normal cancellations and lower orders in prior periods. However, we did see a sequential improvement in early development, gross orders and cancellations, which we expect will lead to higher revenues in the second half of the year and deliver year-over-year growth beginning in the fourth quarter.
Biopharma adjusted operating income for the quarter was $107 million or 15.2% of revenue compared to $105 million or 15% last year. Adjusted operating income and margin increased due to organic growth and LaunchPad savings, partially offset by higher personnel costs. We ended the quarter with a backlog of $7.9 billion and we expect approximately $2.5 billion of this backlog to convert into revenue over the next 12 months. The trailing 12 months book-to-bill held at 1.00 compared to last quarter and is expected to increase in the second half.
Now I'll discuss our updated 2024 full year guidance, which assumes foreign exchange rates effective as of June 30, 2024, for the remainder of the year. The enterprise guidance also includes the impact from currently anticipated capital allocation, with free cash flow targeted for acquisitions, share repurchases and dividends. The acquisition of select assets of Invitae, which is expected to close next week, is now included in our guidance for 2024.
For the remainder of the year, we expect Invitae to add approximately $120 million in revenue, lower adjusted earnings per share by approximately $0.40 and reduced cash flow by approximately $150 million, primarily due to onetime costs related to retention, severance and integration as well as an increase in working capital. We expect Enterprise revenue to grow 6.4% to 7.5% compared to 2023 versus prior guidance, we are increasing the midpoint 135 basis points with Invitae contributing approximately 100 basis points of the growth.
We continue to perform well in Diagnostics. We expect Diagnostics revenue to be up 6.9% to 7.9% compared to 2023. This is an increase at the midpoint from our prior guidance of 200 basis points due to stronger base business demand and Invitae, which is expected to contribute around 130 basis points of the growth. We expect Biopharma revenue to grow 3.7% to 5% compared to 2023. The decrease at the midpoint from our prior guidance of 35 basis points is due to early development, partially offset by continued strength in central labs. We expect Early Development to have a slower recovery than previously anticipated, but with year-over-year growth still expected to begin in the fourth quarter.
We expect enterprise margins to be flat versus the prior year despite the negative impact from Invitae of approximately 40 basis points. Diagnostics margins are now expected to be down due to the inclusion of Invitae of approximately 60 basis points. We continue to expect margins in biopharma to be up year-over-year.
Our guidance range for adjusted EPS is $14.30 to $14.90. We have decreased the midpoint of guidance by $0.30, driven by the expected dilution from Invitae of approximately $0.40 and partially offset by a $0.10 increase in the underlying business. The free cash flow guidance range is now $850 million to $1 billion and includes approximately $150 million of a cash use from Invitae, which is primarily due to onetime costs. Excluding Invitae, the free cash flow guidance range is unchanged from prior guidance.
In summary, Labcorp is well positioned for profitable growth, both organically as well as through acquisitions. We're excited about the acquisition of Invitae from both a strategic and financial perspective. Strategically, this strengthens our position in key long-term specialty testing growth areas of oncology and select rare diseases. From a financial perspective, while it's dilutive in 2024, we expect it to be accretive in 2025 and deliver a very attractive return on investment as we profitably grow the business. In addition, Labcorp continues to generate strong free cash flow that will be used for acquisitions while returning capital to shareholders through our dividend and share repurchase program.
Operator, we'll now take questions.