Pfizer Inc. (NYSE: PFE) reported financial results for first-quarter 2021 and raised 2021 guidance for revenues and adjusted diluted EPS (Earnings per share) driven by the updated expectations for contributions to 2021 performance from the Pfizer-BioNTech SE (BioNTech) COVID-19 vaccine, as well as the strong performance of the business excluding this partnership, partially offset by anticipated additional R&D investments into vaccines to protect against COVID-19, as well as other mRNA-based development programs and COVID-19 antivirals.

Following the completion of the spin-off of the Upjohn Business in the fourth quarter of 2020, Pfizer now operates as a focused innovative biopharmaceutical company engaged in the discovery, development, manufacturing, marketing, sales and distribution of biopharmaceutical products worldwide.

Revenues and expenses associated with the Upjohn Business for first-quarter 2020 have been recategorized as discontinued operations and excluded from adjusted results. Pfizer’s Meridian subsidiary, the manufacturer of EpiPen and other auto-injector products, which had been reported within the results of the Upjohn Business in the first three quarters of 2020, is now included within the Hospital therapeutic area for all periods presented.

First-quarter 2021 revenues totaled $14.6 billion, an increase of $4.5 billion, or 45%, compared to the prior-year quarter, reflecting operational growth of $4.2 billion, or 42%, as well as a favorable impact of foreign exchange of $284 million, or 3%.

Compared with the prior-year quarter, first-quarter 2021 revenues were favorably impacted by approximately $400 million as a result of first-quarter 2021 having three additional selling days in the U.S. and four additional selling days in international markets. This increase in selling days will be offset in fourth-quarter 2021, resulting in essentially the same number of selling days in full-year 2021 as full-year 2020.

The favorable impact in first-quarter 2021 from selling days was partially offset by the non-recurrence of favorable impacts related to COVID-19 on first-quarter 2020, including increased demand for certain products of approximately $150 million and additional wholesaler inventories of approximately $100 million.

The net favorable impact on first-quarter 2021 revenues of all of the above factors was approximately $150 million, accounting for approximately 1.5 percentage points of operational growth. First-quarter 2021 operational growth was primarily driven by Covid-19 vaccine, which contributed $3.5 billion in global revenues.

Business development activities completed in 2020 and 2021 impacted financial results in the periods presented.

2021 financial guidance

Pfizer is raising its guidance ranges for revenues, Adjusted cost of sales as a percentage of revenues, Adjusted R&D expenses and Adjusted diluted EPS to reflect the updated expectations for contributions to 2021 performance from BioNTech) COVID-19 and the continued strong performance of the business excluding that, partially offset by anticipated additional R&D investments into vaccines to protect against COVID-19, as well as early research investments into other mRNA-based development programs and COVID-19 antivirals.