CSL Ltd (ASX: CSL) shares have had a rough run this year.
The biotech giant ended last week at $212.47, meaning its share price has tumbled about 28% over the past year.
For a company long viewed as one of the ASX's most dependable performers, that is a serious shock.
So, what has gone wrong for this blue chip share, and could this actually be a buying opportunity for long-term investors? Let's look deeper into things.
Short-term headwinds weigh on sentiment
CSL remains one of the highest-quality businesses on the ASX. It develops and manufactures plasma therapies, vaccines, and specialty medicines used by millions of patients globally.
However, investors have grown concerned about short-term challenges.
In its FY 2025 results, CSL reported solid revenue and profit growth but still fell short of expectations due to its key CSL Behring business.
The team at E&P summarised why investors were hitting the sell button after the results. It said:
[CSL] Behring drove the gross profit shortfall in 2H25 and into FY26, with sales more heavily affected than expected by the US Medicare Pt D redesign (-1.9% vs. our -1.0%), and the loss of several ex-US Ig tenders (-3–4% sales impact in FY26). Margins were lower for several reasons, most notably the Medicare Pt D impact which is all margin, and additional investment in headcount for the Rika/i-nomogram rollout. CSL also stepped away from previous Behring GP margin guidance; they still expect to get there, all the levers are still in place, but they are no longer committing to timing (i.e. it's likely been pushed out).
In addition, there are concerns about the impact of US pharmaceutical tariffs and the uncertainty caused by plans to spin off its CSL Seqirus vaccines business.
The long-term picture remains strong
Despite the above, CSL's growth story is far from over. Plasma collections are rebounding strongly after pandemic disruptions, and demand for its therapies continues to expand worldwide.
The company is also investing heavily in next-generation facilities and a world-class R&D pipeline to sustain its leadership for decades to come.
CSL has weathered plenty of market storms before. Each time, it has emerged stronger, which is a testament to the resilience of its business model and the essential nature of its products.
Should you buy CSL shares?
For investors with a long-term mindset, this pullback could be a gift.
The company is still growing, it is still profitable, and it is still one of the best-run biotechs in the world.
Analysts at Macquarie remain confident in the investment opportunity here. They recently maintained their outperform rating on CSL shares with a $275.20 price target. This implies potential upside of around 30% from current levels.
Overall, while the market frets over short-term headwinds, patient investors could be setting themselves up for long-term gains by buying CSL shares while they are trading at a rare discount.
