Welcome to Virtual Investor Conferences. On behalf of OTC Markets and our co-host, Zacks Small Cap Research, we're very pleased you joined us for our quarterly Life Sciences Conference. Our first presentation of the second day of the event is from CSL. Please note you may submit questions for the presenter in the box to the left of the slides. You can also view a company's availability for one-on-one meetings by clicking "Book Meeting" in the top toolbar. At this point, I'm very pleased to welcome Bernard Ronchi. He's the Director of Investor Relations of CSL, which trades on the OTCQX Best Market under the symbol CSLLY and on the ASX under the symbol CSL. Welcome, Bernard.
Thank you, John, and good evening or good morning, everyone. As John said, I'm Bernard Ronchi, the Director of Investor Relations for CSL Limited. CSL is a global biotech company that is headquartered down in Melbourne, Australia, which I will talk to you about shortly. I've been at CSL for nearly 10 years, and I'm pleased to be able to present to you today, and I thank you for your interest. Before I begin, I draw your attention to the disclaimer up on the screen now. This relates to the information provided throughout the presentation today. A little bit about CSL. CSL began more than a century ago as the Commonwealth Serum Laboratories under the Australian government.
Today, CSL is a global biotech company that develops and delivers innovative medicine that helps people with serious and life-threatening conditions live full lives and protect the health of communities around the world. We have market-leading positions in large and growing markets. As you can see on the slide, we are either number one or number two in the major sectors that we operate in. CSL was privatized and listed on the Australian Securities Exchange in 1994, and since then, we have achieved a great deal as a public company. We currently provide life-saving products to patients in more than 100 countries and employ around 32,000 people globally. Around 2,000 of these people are scientists in our research and development team, where we have an annual spend of over $1 billion a year to develop our pipeline of new and innovative products.
We have also spent over $5 billion in capital expenditure over the last five years to expand our capacity to meet the expected future demand for our medicines. What does CSL do? At CSL, as I said, we are a global biotech company with a dynamic portfolio of life-saving medicines. We comprise three business units. There's CSL Behring, which develops and delivers innovative therapies for people living with rare and serious diseases across a range of therapeutic areas. As you can see, this is the real growth engine of the business, accounting for over 70% of our revenue in the 2024 financial year. In order to produce many of these therapies, we rely on human plasma. At CSL Plasma, we operate one of the world's largest and most sophisticated plasma collection networks, with nearly 350 collection centers, predominantly in the U.S. and Europe.
As one of the largest influenza vaccine providers in the world, CSL Seqirus is a major contributor to the prevention of influenza globally and a leading partner in pandemic preparedness. We also have been a partner of choice for governments around the world in mitigating the risk of avian influenza. Thirdly, we have CSL Vifor, a global partner of choice for innovative leading therapies in iron deficiency and nephrology. I'll quickly go through our strategy. CSL is a company that operates with a long-term mindset. Our strategy in its current form was devised in 2019 and is up on the screen now. At the heart of our organization are our people and culture, our values, and our commitment to patients and public health. We have five key areas of our strategy. It really starts with focus. I've said before that in the biotech industry, it's easy to get distracted.
CSL has typically been very deliberate about targeting areas where we know we can develop a competitive advantage. Innovation has also been vital to our success so far and will continue to underpin CSL's future. Our work in hereditary angioedema is a great example of this. We have been improving on our offering to patients for 15 years and are in the process of launching a new product called ANDEMBRY, which is an Australian homegrown monoclonal antibody, which we believe will become the standard of care for those suffering from HAE. We know that to remain a top-tier company, we need to focus not only on reliability, but maximizing efficiency. This manifests through technology and continuous improvement and reinvesting in our business. I'll talk a little bit more about this shortly.
For the sustainable growth of the enterprise, we are committed to serving our populations with the best available therapies across our strategic scientific platforms, which I'll also talk to shortly. Finally, we are progressing on our digitization journey, and we are very focused on simplifying our technology platforms, leveraging digital technology, including generative AI where it makes sense. As I said, CSL was listed on the ASX in 1994, and since then, we have been on a consistent growth trajectory enabled by this strategy that I just talked about. This is a very strong track record, but we realize that this type of performance will not be afforded to us in the future if we do not work hard and make the right strategic and capital allocation decisions today. We have leading positions in large global markets with significant unmet need.
This, along with the investments we have made into our business, underpins our confidence that we are well-positioned for long-term growth. In terms of our global presence, as you can see on this slide, on the Behring side of the business, we have large modern manufacturing plants in Switzerland, Australia, the United States, and Germany. For our other businesses, so for Seqirus, our facilities are located in the U.K., North Carolina in the United States, and also in Australia. In Melbourne, we are in the process of transitioning from our Parkville site, which has been operating for over 100 years, to our new state-of-the-art facility at Tullamarine, which is just near the Melbourne Airport. This will be operational in the coming year.
As you can see, we have a truly global operational footprint, and this has been a big focus for a lot of our investors and shareholders in light of President Trump's recent tariff announcements. I'll just quickly touch on that. This, of course, is a very fluid situation, but I'd like to make a few comments as we've been getting a lot of questions from investors of late. There's been a Section 232 investigation into potential tariffs on pharmaceutical products. We are openly participating in this consultation, but I want to share a few important points in relation to tariffs with you. Firstly, patients around the world rely on our essential products to live or maintain their quality of life. Any impediment to this is harmful to public health. CSL employs more than 19,000 people across 44 U.S. states, about 60% of our global workforce.
Over the past seven years alone, we have invested more than $3 billion across our U.S. manufacturing, plasma collection, and corporate operations. The CSL Behring, all the plasma products that we produce for U.S. patients, are derived from plasma that is sourced within the U.S., and this is where the majority of our value creation occurs. We believe this is consistent with the U.S. administration's policy objectives and should preclude these products from being subject to any future potential tariffs on the pharmaceutical sector. Of course, we can't say this with complete certainty at this stage. For Seqirus, it operates a manufacturing plant in Holly Springs, North Carolina, which makes the majority of our vaccines for the U.S. market. Seasonal flu vaccine doses coming into the U.S. from our overseas manufacturing sites are limited.
For V4, there are certain businesses or products, I should say, that may be impacted, which we are working through mitigation strategies to optimize our global supply chain. As you would expect, we've been monitoring this situation very closely and have been planning different scenarios for many months. Our global supply chain is proving to be a helpful asset right now, and we continue to work through opportunities to further optimize this, recognizing that any changes could take time. We are prepared to implement further mitigation strategies should they be required. A little bit about our recent results, which is on the screen now. These are the results, our half-year results, which we presented to the market in February for the six months up to 31 December 2024.
CSL delivered a solid result for the first half of financial year 2025, driven by a strong performance by the CSL Behring business and also growth in CSL Vifor. Importantly, we reaffirmed our guidance to the market for fiscal year 2025, which was for NPATA growth of between 10% and 13%. Just quickly, the headline numbers were as follows: revenue was $8.5 billion, up 5% at constant currency. NPATA was $2.1 billion, also up 5%, while our net profit after tax was $2 billion, up 7%. In terms of the major highlights for the period, the CSL Behring business delivered strong growth of 10%, driven once again by our immunoglobulins franchise, which grew 15%, and another robust performance by albumin. The gross margin for CSL Behring continues to improve and was up 170 basis points at constant currency.
We are rolling out some new plasmapheresis machines at our plasma collection centers called RECA, and this is well advanced, and we expect to have this complete by the end of this month. We have also implemented a new iNomogram technology in our centers as well, and this is delivering planned benefits as expected. The growth of HEMGENIX, which is a gene therapy product for Hemophilia B, is going well. It's slow and steady, and we've had four-year data that's come out to reinforce the strength of this product, which is a really outstanding set of results for that product. We also have a product which, as I mentioned before, ANDEMBRY, which is for patients suffering HAE. This is currently with the FDA at the moment, and we expect to hear from them very shortly.
We've already had approvals for this product in Japan, Australia, U.K., and Europe, and, as I said, just waiting on the FDA. In our Seqirus business, its performance has been negatively impacted by the significant decline in influenza immunization rates in the U.S., specifically in the 18- to 64-year-old cohort, which has led to competitive pressures. While this has been a disappointing outcome for public health, there are signs that vaccination rates outside the U.S. are stabilizing. During this period, CSL Seqirus secured several pandemic tenders for avian influenza, which will deliver revenue in our second half. Switching over to CSL Vifor, this business delivered revenue growth of 6%, driven by both iron and nephrology. Ferinject, which is the high-dose iron product, delivered volume growth of 6% in Europe, despite competition from generic market entrants.
In our nephrology segment, which is focused on therapies targeting kidney disease, TAVNEOS performed strongly, and we successfully launched a treatment called FILSPARI in Europe. Moving on to the next slide, I'll now talk a little bit more about the future of CSL. On the screen now, you can see our therapeutic areas that we focus on. I'd just like to remind you of the areas that we concentrate on. These are on the screen now. Improving our R&D productivity is a significant priority for us. With the accelerating speed of science, we have to further strengthen our product development and commercialization capabilities after a few setbacks we've had in the past.
This means accelerating our development pipelines, sharpening our focus areas, and being clear about where we add value internally versus externally, enhancing lifestyle management opportunities, of which we believe there are many, as well as exploring new novel molecules, and partnering more effectively with external innovators. This isn't about material M&A; it's about partnerships and collaboration opportunities that will enable us to accelerate development. Moving on to the next slide is capital management. The investment process underpins the future of our business. Allocating capital to its most valuable use is the most important task we have. Our goal is to maximize shareholder value, so it is important that our shareholders understand this process. I'd like to talk about this referencing the framework you can see on the slide now. First, we aim to maintain our efficient balance sheet, and we don't want to be too highly geared.
Our gearing ratio at the moment is around two times, and we think that will continue to deleverage. We do, however, have a strong appetite to retain our investment-grade credit ratings. A few years ago, we made a significant investment in acquiring the Vifor pharma business, and we see great potential for this business, which fits in well with our ambition to deliver enduring patient impact, addressing high areas of unmet medical need. Since then, we have been actively deleveraging the balance sheet, and I'm pleased to say this is progressing to plan. We continue to assess all options for capital management beyond that. Moving to shareholder returns, our spend on research, sorry, our dividend practice has been consistent for many years. We aim to grow our dividend in line with the growth in the company's profitability, with a typical payout ratio over the year of between 40 and 45%.
To reinvestment, our spend on research and development underpins the sustainability of our future growth. It's imperative that we continue to innovate in our platforms and in new therapies for medicines. Our capital expenditure is, of course, another way to invest back into the business, increasing capacity to support sales, building new capabilities to support production of new products, as well as directing maintenance CapEx to our existing sites. Finally, cost control is an important part of this discussion as well. We must drive greater efficiencies across the organization, and we are in the process of reviewing a range of initiatives. We must remain committed to being the most efficient plasma collector.
As we near completion of the rollout of the RECA plasmapheresis machines and the iNomogram in our plasma centers, we are delivering improved yields as expected, and we continue to focus on the next phase of center efficiencies and optimize our collection network. We are exploring opportunities outside of our manufacturing network to streamline our footprint, to reduce fixed costs, and increase productivity. We are also simplifying our technology platforms and seeking to further reduce the cost of low-value activities. While our core business remains strong, we are laser-focused on cost control, and we will share our plans as we continue to formulate them. Finally, I'd just like to finish up with a summary and make a few comments about the company's growth outlook. CSL has demonstrated a strong track record of success over a long time frame.
We are well positioned to keep delivering sustainable and profitable growth well into the future. We have leading positions in high-growth markets where there is significant unmet patient need. We have durable products driven by our continued innovation. We have made substantial capital investment to expand our manufacturing network and now have the capacity to meet demand and deliver future growth. As part of our capacity expansion, we have also invested in new innovative processes to deliver higher Ig and vaccine yields, improving efficiencies. Underpinning this is our disciplined approach to capital allocation. Our strong cash flows enable us to maintain a strong balance sheet, reinvest back into the business, and deliver returns back to our shareholders. I will conclude my presentation, and happy to take your questions. There has been a couple that have come through already.
The first one, what is your dividend policy, and do you have an active buyback plan? We do not have a formal dividend policy as such, but as I mentioned in the presentation, we aim to deliver or return around 40-45% of our profits to shareholders and then reinvest the rest back into the business, either through R&D, CapEx, etc. Yeah, around 40-45% of our profit is paid in the form of dividends. The next question is, can you discuss the prospect for your avian flu vaccine and U.S. government award? As I said in my presentation, we have been successful in securing a number of avian flu contracts for governments around the world.
We have won about 90% of the contracts on the market, and most of this revenue will be delivered in the second half of our financial year 2025, so in the six months just finishing now. I mean, avian flu is still around, so we may see some more contracts in the future, and we are well placed if that does happen. Obviously, we do not want a pandemic, but as I said, we are well placed to secure more contracts if that is the case. Another question, can you speak to your growth drivers over the next several years? There is organic growth within the business, so we think there is still large growth potential in all our business, particularly the Behring business.
Demand for our products is growing at sort of high single digits, our plasma products, underpinned by the growth in our immunoglobulins, and we see good medium-term growth in that business. Even though I mentioned that Seqirus, which is our vaccines business, has had a difficult time of late, we do think that vaccination rates will recover. It is a cyclical business. We think they will recover over time, and Seqirus has a really good portfolio of influenza products, namely the cell-based product, and we have an adjuvanted product, which we call FluAd. They are really good products, and we think once vaccination rates pick up, we are in a strong position to continue to grow that business. With Vifor, our other business, there is really good potential for the iron product.
When we took over Vifor, they were only sort of selling into 20 or 30 countries, whereas the CSL footprint, we sell into over 100 countries, so there's good opportunity to expand the iron portfolio. We've recently launched in China and Canada as well, so we think there's some other good markets for iron. And then for nephrology, we also think there's good growth in the renal business. As I said, we've launched a couple of products recently that have been growing strongly. Another question, has CSL been active in M&A? CSL hasn't really been an acquisitive company. I mean, in the early 2000s, if I give you a bit of background, CSL, as I said, was spun out of the Australian government in the 1990s, and we made a couple of large acquisitions in the early 2000s.
Aventis Behring was one, and we also made an acquisition in Switzerland, and that really kind of set the company up to what it is today. Since then, we've made a couple of acquisitions. We bought some flu assets from Novartis in 2015, and that became the CSL Seqirus business. In 2022, we bought CSL Vifor in Switzerland. Whilst I say we haven't been that acquisitive, we have made a few acquisitions over the years. We're still bedding down the Vifor acquisition. It's been two years now, so we don't have any appetite in the sort of near-term for any material M&A transactions. We may look to do some smaller business development deals, like buying in some R&D assets, licensing some products, perhaps where we have some gaps in our pipeline. That's kind of the strategy at the moment.
I think that's all the questions that I have for now. If there are any others, feel free to put them in the chat. Given there are no other questions, I think I'll wrap it up there. My contact details are on the screen now. You'll see my email. Also, if you go to our website, csl.com.au, you'll also find my contact details in the investors section. Thank you very much for your time. Yeah, if anyone has any more questions, feel free to get in touch. Thank you very much.