
	Statement of Operations Classification	Three Months Ended March 31,
(In millions)		2021		2020
Antibody:
Regeneron's share of profits in connection with commercialization of antibodies	Collaboration revenue	$	260.6	$	170.9
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	105.6	$	80.1
Reimbursement of research and development expenses	Reduction of Research and development expense	$	30.1	$	77.6
Regeneron's obligation for its share of Sanofi research and development expenses	Research and development expense	$	(11.9)	$	(16.7)
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	60.4	$	91.2

Immuno-oncology:
Regeneron's share of losses in connection with commercialization of Libtayo outside the United States	Collaboration revenue	$	(6.1)	$	(6.2)
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	4.7	$	2.1
Reimbursement of research and development expenses	Reduction of Research and development expense	$	21.9	$	39.9
Reimbursement of commercialization-related expenses	Reduction of Selling, general, and administrative expense	$	18.5	$	10.4
Regeneron's obligation for Sanofi's share of Libtayo U.S. gross profits	Cost of goods sold	$	(30.4)	$	(26.8)
Amounts recognized in connection with up-front payments received	Other operating income	$	22.9	$	16.5

The Company is party to a global, strategic collaboration with Sanofi to research, develop, and commercialize fully human monoclonal antibodies (the "Antibody Collaboration"), which currently consists of Dupixent® (dupilumab), Kevzara® (sarilumab), and itepekimab. Under the terms of the Antibody License and Collaboration Agreement ("LCA"), Sanofi is generally responsible for funding 80%–100% of agreed-upon development costs.

In April 2020, the Company and Sanofi entered into an amendment to the LCA in connection with, among other things, the removal of Praluent from the LCA such that (i) effective April 1, 2020, the LCA no longer governs the development, manufacture, or commercialization of Praluent and (ii) the quarterly period ended March 31, 2020 was the last quarter for

which Sanofi and the Company shared profits and losses for Praluent under the LCA. The parties also entered into a Praluent Cross License & Commercialization Agreement (the "Praluent Agreement") pursuant to which, effective April 1, 2020, the Company, at its sole cost, became solely responsible for the development and commercialization of Praluent in the United States, and Sanofi, at its sole cost, became solely responsible for the development and commercialization of Praluent outside of the United States. Under the Praluent Agreement, Sanofi will pay the Company a 5% royalty on Sanofi’s net product sales of Praluent outside the United States until March 31, 2032. The Company will not owe Sanofi royalties on the Company’s net product sales of Praluent in the United States. Although each party will be responsible for manufacturing Praluent for its respective territory, the parties have entered into definitive supply agreements under which, for a certain transitional period, the Company will continue to supply drug substance to Sanofi and Sanofi will continue to supply finished product to Regeneron.

With respect to any intellectual property or product liability litigation relating to Praluent, the parties have agreed that, effective April 1, 2020, Regeneron and Sanofi each will be solely responsible for any such litigation (including damages and other costs and expenses thereof) in the United States and outside the United States, respectively, arising out of Praluent sales or other activities on or after April 1, 2020 (subject to Sanofi's right to set off a portion of any third-party royalty payments resulting from certain patent litigation proceedings against up to 50% of any Praluent royalty payment owed to Regeneron). The parties will each bear 50% of any damages arising out of Praluent sales or other activities prior to April 1, 2020. See Note 12 for discussion of legal proceedings related to Praluent.

The Company is party to a collaboration with Sanofi to research, develop, and commercialize antibody-based cancer treatments in the field of immuno-oncology (the "IO Collaboration"). The IO Collaboration is governed by an Amended and Restated Immuno-oncology Discovery and Development Agreement ("Amended IO Discovery Agreement"), and an Immuno-oncology License and Collaboration Agreement ("IO License and Collaboration Agreement").

Effective December 31, 2018, the Company and Sanofi entered into the Amended IO Discovery Agreement, which narrowed the scope of the existing discovery and development activities conducted by the Company under the 2015 IO Discovery Agreement to developing therapeutic bispecific antibodies targeting (i) BCMA and CD3 (the "BCMAxCD3 Program") and (ii) MUC16 and CD3 (the "MUC16xCD3 Program") through clinical proof-of-concept. During the first quarter of 2021, Sanofi did not exercise its options to license rights to these product candidates; as a result, we retain the exclusive right to develop and commercialize such product candidates and Sanofi will receive a royalty on sales (if any). In addition, the Company has no further obligations to to develop drug product candidates under the Amended IO Discovery Agreement.

Under the terms of the IO License and Collaboration Agreement, the parties are co-developing and co-commercializing Libtayo (cemiplimab), an antibody targeting the receptor known as programmed cell death protein 1 (PD-1). The parties share equally, on an ongoing basis, agreed-upon development and commercialization expenses for Libtayo. The Company has principal control over the development of Libtayo and leads commercialization activities in the United States (see Note 2 for related product sales information), while Sanofi leads commercialization activities outside of the United States. The parties share equally in profits and losses in connection with the commercialization of Libtayo.

The aggregate amount of the estimated consideration under the IO Collaboration related to the Company's obligation that was unsatisfied (or partially unsatisfied) as of March 31, 2021 was $515.4 million. This amount is expected to be recognized over the remaining period in which the Company is obligated to satisfy its obligation in connection with performing development activities.

The Company is party to a license and collaboration agreement with Bayer for the global development and commercialization of EYLEA outside the United States. All agreed upon EYLEA development expenses incurred by the Company and Bayer are shared equally. Bayer markets EYLEA outside the United States, where, for countries other than Japan, the companies share equally in profits and losses from sales of EYLEA. In Japan, the Company is currently entitled to receive a tiered percentage of between 33.5% and 40.0% of EYLEA net product sales through 2021, and thereafter, the companies will share equally in profits and losses from sales of EYLEA.


	Statement of Operations Classification	Three Months Ended March 31,
(In millions)		2021		2020
Regeneron's net profit in connection with commercialization of EYLEA outside the United States	Collaboration revenue	$	308.9	$	253.8
Reimbursement for manufacturing of commercial supplies	Collaboration revenue	$	13.9	$	27.6
Reimbursement of research and development expenses	Reduction of Research and development expense	$	10.8	$	12.0
Regeneron's obligation for its share of Bayer research and development expenses	Research and development expense	$	(12.5)	$	(8.1)

The Company and Teva are parties to a collaboration agreement (the "Teva Collaboration Agreement") to develop and commercialize fasinumab globally, excluding certain Asian countries that are subject to our collaboration agreement with Mitsubishi Tanabe Pharma Corporation. The Company leads global development activities, and the parties share development costs equally, on an ongoing basis, under a global development plan. The Company is also responsible for the manufacture and supply of fasinumab globally.


	Statement of Operations Classification	Three Months Ended March 31,
(In millions)		2021		2020
Reimbursement of research and development expenses	Reduction of Research and development expense	$	19.8	$	25.2
Amounts recognized in connection with up-front and development milestone payments received	Other operating income	$	12.2	$	16.6

The aggregate amount of the estimated consideration under the Teva Collaboration Agreement related to the Company's obligation that was unsatisfied (or partially unsatisfied) as of March 31, 2021 was $123.9 million. This amount is expected to be recognized over the remaining period in which the Company is obligated to satisfy its obligation in connection with performing development activities.

In the first quarter of 2020, we announced an expansion of our Other Transaction Agreement with the Biomedical Advanced Research Development Authority ("BARDA"), pursuant to which the U.S. Department of Health and Human Services ("HHS") was obligated to fund certain of our costs incurred for research and development activities related to COVID-19 treatments. In July 2020, we entered into an agreement with entities acting at the direction of BARDA and the U.S. Department of Defense to manufacture and deliver filled and finished drug product of REGEN-COV to the U.S. government. During the first quarter of 2021, the Company completed its final deliveries of drug product under this agreement. See Note 2 for REGEN-COV net product sales recognized in connection with this agreement during the three months ended March 31, 2021.

In January 2021, the Company announced an agreement with an entity acting on behalf of the U.S. Department of Defense and HHS to manufacture and deliver additional filled and finished drug product of REGEN-COV to the U.S. government. Pursuant to the agreement, the U.S. government is obligated to purchase all filled and finished doses of drug product delivered by June 30, 2021, and may accept doses during the period from July 1, 2021 through September 30, 2021 at its discretion. The U.S. government will acquire doses at the lowest treatment dose authorized or approved by the FDA for the indication authorized under the EUA, resulting in payments to the Company of up to $2.625 billion in the aggregate. During the three months ended March 31, 2021, we did not recognize any net product sales in connection with this agreement.

In August 2020, we entered into a collaboration agreement (the "Roche Collaboration Agreement") with Roche to develop, manufacture, and distribute the casirivimab with imdevimab antibody cocktail (known as REGEN-COV in the United States). We continue to lead global development activities for casirivimab with imdevimab, and the parties jointly fund certain ongoing studies, as well as any mutually agreed additional new global studies to evaluate further the potential of casirivimab with imdevimab in treating or preventing COVID-19. Roche will be responsible for securing regulatory approvals outside the United States, following the initial European Medicines Agency ("EMA") approval (if any), and conducting any additional studies specifically required for approval by regulators outside the United States.

Under the terms of the agreement, each party is obligated to dedicate a certain amount of manufacturing capacity to casirivimab with imdevimab each year. We distribute the product in the United States and Roche distributes the product outside of the United States. The parties share gross profits from worldwide sales based on a pre-specified formula, depending on the amount of manufactured product supplied by each party to the market.


	Statement of Operations Classification	Three Months Ended March 31,
(In millions)		2021		2020
Regeneron's share of gross profits in connection with sales of casirivimab with imdevimab	Collaboration revenue	$	66.8	—
Reimbursement of research and development expenses	Reduction of Research and development expense	$	86.8	—