CSL (ASX: CSL) has reported its first-half results for FY21. We take a look at the company's headline figures, key commentary and guidance outlook, plus review the share market's reaction across the trading day.

Headline result

CSL has today unveiled a 45% increase in reported net profit after tax, with the company generating US$1.81bn across the half-year ending December 31, 2020. Meanwhile, sales revenue grew by 18% to reach US$5.6 billion. In constant currency terms, both metrics were broadly in line with these same numbers.Supporting the strength of the result, the global biotechnology firm has declared a bumper dividend of US$1.04 per share. This payment will be 9% higher than a year ago in USD-denominated terms, however, adverse currency movements mean that it will be 9% lower than the prior corresponding period when converted to Australian currency. The ex-dividend date for CSL shares is Thursday, March 4. Payment will be made to shareholders on Thursday, April 1.

Key commentary

Once again, CSL's core immunoglobulin portfolio has proven to be a standout for the company, particularly the HIZENTRA product.Sales for the HIZENTRA product, designed to treat the neurological condition of Chronic Inflammatory Demyelinating Polyneuropathy, were 19% higher than in 1H FY20. Management cited the benefit of home administration in driving sales growth, whereas there was only "modest" growth for intravenous product PRIVIGEN, which was also impacted by supply issues amid COVID-19.Following the transition to an internal distribution model in China, sales for Albumin soared 93%, returning to normalised levels as forecast a year ago.After manufacturing constraints weighed on the production of its HAEGARDA product in the prior corresponding period, these problems now seem a distant memory for the company as sales growth was restored by 16%.Within the influenza division, the company's Seqirus product performed exceptionally well, with total revenue up 38% and EBIT more than doubling to US$693 million. High demand for seasonal flu vaccines (+44%) underpinned the result, while a shift in the product portfolio mix optimised earnings.Elsewhere, there were 17 new plasma collection centres opened by the company in the US across the half.

CSL's half-year results also include a one-off contribution related to vaccine development works that it performed in conjunction with the University of Queensland, and which have since concluded.

Guidance outlook

The company has provided guidance that FY21 net profit after tax is set to be in the range of approximately US$2.17 billion to US$2.27 billion at constant currency, which would represent growth of 8%. According to the company, this is supported by "robust" demand for its core plasma and influenza vaccine products. Notwithstanding the strength of its vaccine portfolio, a seasonal drop-off in demand for influenza vaccine over the second-half of the year will lead to losses in the Seqirus segment for the period.

The impact of COVID-19 on CSL's plasma collection centres continues to be felt, although the company is responding to this by seeking to drive increased plasma collection and equitable distribution of medicine.

In light of CSL concluding its primary efforts to work towards a COVID-19 vaccine candidate, the company will ramp up operational and R&D expenditure as it restarts postponed projects. With that said, CSL is currently manufacturing the AstraZeneca COVID-19 vaccine with the first doses planned for release in late-March, 2021.