Grifols' performance in the first half and particularly the second quarter clearly shows the ongoing efforts we have made to confront the challenges of COVID-nineteen, but also our delivery on our commitments to reduce debt and our ability to secure long term growth, investing in plasma capacity, innovation and global expansion. Our 2nd quarter revenues were especially strong with a 5.3% growth at constant currency, Thanks to solid performance by Bioscience, Diagnostic and Hospital. Bioscience revenue grew 5.1% in the 2nd quarter, a notable improvement after declining 5.6 percent in the first quarter. We saw strong demand for all key including intravenous immunoglobulin subcutaneous albumin alpha-one and specialty proteins. Revenue growth was also back by mid single digit price increases.
Diagnostics reported another strong quarter and grew double digit, thanks to revenues of the SARS CoV-two test and underlying NAT technology solutions. Hospital also grew double digit in the 2nd quarter and over the first half with the pharmatec and the intravenous therapy lines as the main growth drivers. Additionally, we'd like to mention the contribution from new products, which represented 5% of our sales in the first half of the year. These results are promising, and we expect to see continued growth. In terms of gross margin, it was still impacted by a higher cost per liter of plasma.
Our €100,000,000 cost savings plan allowed us to deliver an EBITDA margin of 25% while increasing our innovation efforts. Recent strategic acquisitions of roughly $1,000,000,000 have increased our leverage ratio. These are important investments since they'll allow us to secure plasma supply and continue to innovate and expand globally. Deleveraging is a key priority As our result can attest, our debt leverage ratio now stands at 4.9 times, down from 5.1 times in the 1st quarter. Our agreement with GIC, the Sovereign Wealth Fund of Singapore, is an important step forward in our efforts to deleverage.
They'll become a long term strategic investor for the next 30 years, and it will help us reduce our debt leverage ratio by an additional 0.6 times from the Q2 year 2021 levels. We anticipate a neutral P and L effect and we'll allocate all proceeds to repay senior debt. Recent acquisitions and agreements, we have expanded and diversified our supply by 1,400,000 liters capacity per year. We'll also continue to work to meet current and projected strong demand. As of today, plasma collections in Europe are not only ahead of year 2020 levels but also ahead of pre COVID levels.
Collections are on the rise in the U. S. As expected and continue to grow every week. Regarding recent events along the Southern U. S.
Border, we have seen an impact in collections, but it's not significant at this point. In the meantime, we are working with peers and the BPTA to try to address these issues. There is no doubt that we will continue to face challenges in the short term, but our efforts to increase our plasma capacity, optimize our operations, expand into new markets,