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CSL makes life-saving plasma-based medicines and vaccines that treat people with rare and serious diseases.
CSL is a biotech company that turns human blood plasma into medicines. Plasma is the yellowish liquid part of blood, and it contains proteins that help fight infection, clot bleeding, and keep the body working properly. CSL collects plasma from donors at hundreds of centers around the world, then separates it into specialized drugs that treat immune disorders, bleeding disorders, and other rare conditions. It also makes vaccines, including most of the world's flu shots.
The plasma business, called CSL Behring, is the engine. People with conditions like hemophilia or immune deficiencies need these therapies for life, which makes the revenue steady and recurring. The company also runs CSL Seqirus, a major flu vaccine maker, and CSL Vifor, which makes iron-deficiency drugs and helps kidney patients. CSL's biggest challenge is that plasma is expensive and slow to collect—donors need to show up, and each donation takes time—so competition for donors is fierce. CSL spends heavily on research and development to find new uses for plasma proteins and to make its products easier to use. Its main competitors include large drugmakers like Takeda and Grifols, but CSL's scale gives it an edge in collection and manufacturing. The company also invests in gene therapies and new treatments through partnerships and acquisitions, betting that these will reduce reliance on plasma collection over time.
CSL is headquartered in Melbourne and lists on the Australian Securities Exchange. It pays dividends and buys back shares, but its biggest use of cash is expanding plasma collection and manufacturing capacity. One notable fact: the company's origins trace back to a government-run blood lab in Australia in the 1900s, and it later became a private firm that grew into a global powerhouse. Today, it's one of Australia's largest companies by market value.
Saved answer · last researched 19 Oct 2026