Revenues

Product Revenues

Revenues by product are summarized as follows:



	For the Years Ended December 31,
	2018						2017						2016
(In millions)	United States		Rest of World		Total		United States		Rest of World		Total		United States		Rest of World		Total
Multiple Sclerosis (MS):
TECFIDERA	$	3,253.2	$	1,020.9	$	4,274.1	$	3,294.0	$	920.0	$	4,214.0	$	3,169.4	$	798.7	$	3,968.1
Interferon*	1,668.3		694.7		2,363.0		1,889.1		756.7		2,645.8		1,980.3		814.9		2,795.2
TYSABRI	1,025.0		839.0		1,864.0		1,113.8		859.3		1,973.1		1,182.9		780.9		1,963.8
FAMPYRA	—		92.7		92.7		—		91.6		91.6		—		84.9		84.9
ZINBRYTA	—		1.4		1.4		—		52.7		52.7		—		7.8		7.8
Subtotal: MS Product Revenues	5,946.5		2,648.7		8,595.2		6,296.9		2,680.3		8,977.2		6,332.6		2,487.2		8,819.8

Spinal Muscular Atrophy:
SPINRAZA	854.0		870.2		1,724.2		657.0		226.7		883.7		4.6		—		4.6

Biosimilars:
BENEPALI	—		485.2		485.2		—		370.8		370.8		—		100.6		100.6
FLIXABI	—		43.2		43.2		—		9.0		9.0		—		0.1		0.1
IMRALDI	—		16.7		16.7		—		—		—		—		—		—
Subtotal: Biosimilar product revenues	—		545.1		545.1		—		379.8		379.8		—		100.7		100.7

Other:
FUMADERM	—		22.3		22.3		—		39.6		39.6		—		45.9		45.9

Hemophilia:
ELOCTATE	—		—		—		42.2		6.2		48.4		445.2		68.0		513.2
ALPROLIX	—		—		—		21.0		5.0		26.0		268.0		65.7		333.7
Subtotal: Hemophilia product revenues	—		—		—		63.2		11.2		74.4		713.2		133.7		846.9

Total product revenues	$	6,800.5	$	4,086.3	$	10,886.8	$	7,017.1	$	3,337.6	$	10,354.7	$	7,050.4	$	2,767.5	$	9,817.9

*Interferon includes AVONEX and PLEGRIDY.

We recognized revenues from two wholesalers accounting for 32% and 18% of gross product revenues in 2018, 34% and 21% of gross product revenues in 2017 and 35% and 22% of gross product revenues in 2016, respectively.

As of December 31, 2018, two wholesale distributors individually accounted for approximately 27.7% and 15.6% of net accounts receivable associated with our product sales, as compared to 26.5% and 19.0% as of December 31, 2017.

An analysis of the change in reserves for discounts and allowances is summarized as follows:



(In millions)	Discounts			Contractual Adjustments			Returns			Total
2018
Beginning balance	$	109.6		$	606.0		$	46.0		$	761.6
Current provisions relating to sales in current year	679.3			2,686.7			23.1			3,389.1
Adjustments relating to prior years	(0.3		)	(10.0		)	(1.8		)	(12.1		)
Payments/returns relating to sales in current year	(551.7		)	(1,887.6		)	(1.1		)	(2,440.4		)
Payments/returns relating to sales in prior years	(109.1		)	(506.3		)	(31.5		)	(646.9		)
Ending balance	$	127.8		$	888.8		$	34.7		$	1,051.3



(In millions)	Discounts			Contractual Adjustments			Returns			Total
2017
Beginning balance	$	71.6		$	482.7		$	51.2		$	605.5
Current provisions relating to sales in current year	583.0			2,307.4			26.9			2,917.3
Adjustments relating to prior years	(0.1		)	15.0			(8.9		)	6.0
Payments/returns relating to sales in current year	(475.8		)	(1,756.9		)	(0.1		)	(2,232.8		)
Payments/returns relating to sales in prior years	(69.1		)	(442.2		)	(23.1		)	(534.4		)
Ending balance	$	109.6		$	606.0		$	46.0		$	761.6



(In millions)	Discounts			Contractual Adjustments			Returns			Total
2016
Beginning balance	$	56.1		$	548.7		$	57.9		$	662.7
Current provisions relating to sales in current year	592.6			2,044.5			30.9			2,668.0
Adjustments relating to prior years	(1.4		)	1.5			(16.8		)	(16.7		)
Payments/returns relating to sales in current year	(522.5		)	(1,576.0		)	(1.0		)	(2,099.5		)
Payments/returns relating to sales in prior years	(53.2		)	(536.0		)	(19.8		)	(609.0		)
Ending balance	$	71.6		$	482.7		$	51.2		$	605.5

The total reserves above, which are included in our consolidated balance sheets, are summarized as follows:



	As of December 31,
(In millions)	2018		2017
Reduction of accounts receivable	$	176.6	$	189.6
Component of accrued expenses and other	874.7		572.0
Total revenue-related reserves	$	1,051.3	$	761.6

Revenues from Anti-CD20 Therapeutic Programs

Revenues from anti-CD20 therapeutic programs are summarized as follows:



	For the Years Ended December 31,
(In millions)	2018		2017		2016
Biogen's share of pre-tax profits in the U.S. for RITUXAN and GAZYVA, including the reimbursement of selling and development expenses	$	1,431.9	$	1,316.4	$	1,249.5
Other revenues from anti-CD20 therapeutic programs	548.3		242.8		65.0
Total revenues from anti-CD20 therapeutic programs	$	1,980.2	$	1,559.2	$	1,314.5

Approximately 15%, 13% and 11% of our total revenues in 2018, 2017 and 2016, respectively, are derived from our collaboration arrangements with Genentech. For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to these consolidated financial statements.

Other Revenues

Other revenues are summarized as follows:



	For the Years Ended December 31,
(In millions)	2018			2017			2016
Revenues from collaborative and other relationships:
(Loss) profit earned under our 50% share of the co-promotion losses on ZINBRYTA in the U.S. with AbbVie	$	(8.6	)	$	(16.9	)	$	(21.9	)
Revenues earned under our technical development agreement, manufacturing service agreements and royalty revenues on biosimilar products with Samsung Bioepis	96.4			42.7			20.2
Revenues earned under manufacturing services agreement on shipments of ELOCTA and ALPROLIX to Sobi and royalties from Sobi on sales of ELOCTA and ALPROLIX	—			10.7			41.0
Other royalty and corporate revenues:
Royalty	38.7			69.8			46.5
Other corporate	459.4			253.7			230.6
Total other revenues	$	585.9		$	360.0		$	316.4

Other corporate revenues primarily reflect amounts earned under contract manufacturing agreements with our strategic partners, including Bioverativ.

For additional information on our collaboration arrangements with AbbVie and Samsung Bioepis, please read Note 19, Collaborative and Other Relationships, to these consolidated financial statements. For additional information on our contract manufacturing agreements with Bioverativ, please read Note 3, Hemophilia Spin-Off, to these consolidated financial statements.