Also on the call and available for questions are Dr. Carole Ben-Maimon, President of Global Pharmaceuticals; and Michael Nestor, President of Impax Pharmaceuticals.
Our discussion today may include certain forward-looking statements, and actual results may differ from those presented here. The factors that could cause such a difference are outlined in our SEC filings and on our website. Our discussion today includes certain non-GAAP measures as defined by the SEC.
Management uses both GAAP financial measures and the disclosed non-GAAP financial measures internally to evaluate and manage the company's operations and to better understand its business. Further, management believes the inclusion of non-GAAP financial measures provide meaningful supplementary information to and facilitate analysis by investors in evaluating the company's financial performance, results of operations and trends. A reconciliation of GAAP to non-GAAP measures is available in our second quarter 2012 earnings release, which can be found within the Investor Relations section of our website at www.impaxlabs.com.
With that, it's a pleasure to turn our call over to Dr. Larry Hsu.Larry Hsu Thank you, Mark. Good morning, and thanks for joining us. The second quarter was a good revenue and earnings quarter for Impax. Total net revenue increased to 32% to $166 million and adjusted earnings per diluted share increased to $0.41 to $0.60 over last year's second quarter. Our adjusted results benefited from U.S. Zomig tables sales, which we began selling under the Impax Pharmaceutical label on April 1, and the gross profit earnings from AstraZeneca on sales of the Zomig ODT and the nasal spray formulations. These accretive transactions contributed just over 2/3 of the growth in our second quarter 2012 revenue and adjusted EPS, compared to the second quarter of 2011. Also contributing to our year-over-year growth was higher generic Adderall XR sales due to increased delivery from our third-party supplier.