v3.26.1
Revenues
 6 Months Ended
Jun. 30, 2026
Revenue from Contract with Customer [Abstract]  
Revenues
Note 5:
Revenue
Product Revenue
Revenue by product is summarized as follows:
 For the Three Months Ended June 30,
20262025
(In millions)United
States		Rest of
World		TotalUnited
States		Rest of
World		Total
Multiple Sclerosis:
TECFIDERA$32.4 $58.5 $90.9 $47.2 $146.4 $193.6 
VUMERITY172.0 24.5 196.5 188.0 24.3 212.3 
Total Fumarate204.4 83.0 287.4 235.2 170.7 405.9 
AVONEX120.9 49.1 170.0 121.7 56.0 177.7 
PLEGRIDY25.2 29.9 55.1 28.3 40.7 69.0 
Total Interferon146.1 79.0 225.1 150.0 96.7 246.7 
TYSABRI270.5 180.3 450.8 272.2 182.4 454.6 
Subtotal: Multiple Sclerosis621.0 342.3 963.3 657.4 449.8 1,107.2 
Rare Disease:
SPINRAZA204.3 197.6 401.9 149.3 243.4 392.7 
SKYCLARYS82.3 85.6 167.9 78.0 52.3 130.3 
QALSODY8.3 23.6 31.9 7.5 12.5 20.0 
Subtotal: Rare Disease294.9 306.8 601.7 234.8 308.2 543.0 
Specialized Immunology:
SYFOVRE(1)
97.4 — 97.4 — — — 
EMPAVELI(1)
30.4 — 30.4 — — — 
Subtotal: Specialized Immunology127.8 — 127.8 — — — 
Biosimilars:
BENEPALI— 106.8 106.8 — 112.1 112.1 
IMRALDI— 37.8 37.8 — 46.7 46.7 
FLIXABI— 8.1 8.1 — 14.3 14.3 
BYOOVIZ(2)
0.1 — 0.1 2.5 6.1 8.6 
Subtotal: Biosimilars0.1 152.7 152.8 2.5 179.2 181.7 
Other:
ZURZUVAE70.7 0.1 70.8 46.4 — 46.4 
Other(3)
— — — — 0.4 0.4 
Subtotal: Other70.7 0.1 70.8 46.4 0.4 46.8 
Total product revenue, net$1,114.5 $801.9 $1,916.4 $941.1 $937.6 $1,878.7 
(1) EMPAVELI and SYFOVRE were obtained as part of our acquisition of Apellis in May 2026.
(2) In the fourth quarter of 2025 we completed the sale of our rights to BYOOVIZ.
(3) Other includes FUMADERM.
 For the Six Months Ended June 30,
20262025
(In millions)United
States		Rest of
World		TotalUnited
States		Rest of
World		Total
Multiple Sclerosis:
TECFIDERA$63.8 $136.6 $200.4 $87.0 $312.7 $399.7 
VUMERITY325.4 50.1 375.5 305.1 46.0 351.1 
Total Fumarate389.2 186.7 575.9 392.1 358.7 750.8 
AVONEX229.4 103.8 333.2 230.3 114.2 344.5 
PLEGRIDY49.5 69.9 119.4 52.4 76.1 128.5 
Total Interferon278.9 173.7 452.6 282.7 190.3 473.0 
TYSABRI512.3 380.0 892.3 473.0 363.1 836.1 
FAMPYRA(1)
— — — — 0.3 0.3 
Subtotal: Multiple Sclerosis1,180.4 740.4 1,920.8 1,147.8 912.4 2,060.2 
Rare Disease:
SPINRAZA346.5 429.4 775.9 303.7 512.9 816.6 
SKYCLARYS154.1 164.5 318.6 147.1 107.1 254.2 
QALSODY18.8 45.6 64.4 15.0 20.5 35.5 
Subtotal: Rare Disease519.4 639.5 1,158.9 465.8 640.5 1,106.3 
Specialized Immunology:
SYFOVRE(2)
97.4 — 97.4 — — — 
EMPAVELI(2)
30.4 — 30.4 — — — 
Subtotal: Specialized Immunology127.8 — 127.8 — — — 
Biosimilars:
BENEPALI— 228.9 228.9 — 223.4 223.4 
IMRALDI— 87.4 87.4 — 94.1 94.1 
FLIXABI— 18.6 18.6 — 27.4 27.4 
BYOOVIZ(3)
0.1 — 0.1 6.7 10.8 17.5 
TOFIDENCE(3)
— — — 0.1 — 0.1 
Subtotal: Biosimilars0.1 334.9 335.0 6.8 355.7 362.5 
Other:
ZURZUVAE126.0 0.2 126.2 74.1 — 74.1 
Other(4)
— — — 0.4 1.7 2.1 
Subtotal: Other126.0 0.2 126.2 74.5 1.7 76.2 
Total product revenue, net$1,953.7 $1,715.0 $3,668.7 $1,694.9 $1,910.3 $3,605.2 
(1) Effective January 1, 2025, our collaboration and license agreement for FAMPYRA global commercialization rights was terminated.
(2) EMPAVELI and SYFOVRE were obtained as part of our acquisition of Apellis in May 2026.
(3) In 2025 we completed the sale of our rights to TOFIDENCE and BYOOVIZ.
(4) Other includes FUMADERM and ADUHELM.
We recognized revenue from three wholesalers accounting for 29.9%, 16.5% and 10.9%, respectively of gross product revenue for the three months ended June 30, 2026, and 28.7%, 15.7% and 9.8%, respectively of gross product revenue for the six months ended June 30, 2026.
We recognized revenue from two wholesalers accounting for 28.2% and 15.8% of gross product revenue for the three months ended June 30, 2025, and 27.1% and 15.0% of gross product revenue for the six months ended June 30, 2025.
An analysis of the change in reserves for discounts and allowances is summarized as follows:
(In millions)DiscountsContractual
Adjustments		ReturnsTotal
Balance, December 31, 2025$115.7 $1,046.1 $49.0 $1,210.8 
Apellis acquisition13.3 32.3 6.4 52.0 
Current provisions relating to sales in current year439.8 1,352.1 13.4 1,805.3 
Adjustments relating to prior years(2.0)(69.2)13.7 (57.5)
Payments/credits relating to sales in current year(316.1)(745.0)(0.1)(1,061.2)
Payments/credits relating to sales in prior years(129.0)(549.5)(27.9)(706.4)
Balance, June 30, 2026$121.7 $1,066.8 $54.5 $1,243.0 
The total reserves above, which are included in our condensed consolidated balance sheets, are summarized as follows:
(In millions)As of June 30, 2026As of December 31, 2025
Component of accrued expense and other$980.2 $1,000.4 
Reduction of accounts receivable262.8 210.4 
Total revenue-related reserves$1,243.0 $1,210.8 
Revenue from Anti-CD20 Therapeutic Programs
Revenue from anti-CD20 therapeutic programs is summarized in the table below. For the purposes of this footnote, we refer to RITUXAN and RITUXAN HYCELA collectively as RITUXAN.
 For the Three Months Ended June 30,For the Six Months Ended June 30,
(In millions)2026202520262025
Royalty revenue on sales of OCREVUS$381.4 $353.8 $698.6 $642.6 
Biogen’s share of pre-tax profits in the U.S. for RITUXAN, GAZYVA and LUNSUMIO125.7 107.7 220.4 191.4 
Other revenue from anti-CD20 therapeutic programs6.4 5.8 13.6 11.5 
Total revenue from anti-CD20 therapeutic programs$513.5 $467.3 $932.6 $845.5 
For additional information on our collaboration arrangements with Genentech, please read Note 18, Collaborative and Other Relationships, to these condensed consolidated financial statements.
Alzheimer's Collaboration Revenue
Alzheimer's collaboration revenue consists of our 50.0% share of LEQEMBI product revenue, net and cost of sales, including royalties, as we are not the principal. We began recognizing Alzheimer's collaboration revenue upon the accelerated approval of LEQEMBI in the U.S. during the first quarter of 2023.
For the three and six months ended June 30, 2026, we recognized Alzheimer's collaboration revenue of approximately $63.7 million and $123.2 million, respectively, compared to $54.9 million and $87.9 million, respectively, in the prior year comparative periods.
For additional information on our collaboration arrangements with Eisai, please read Note 18, Collaborative and Other Relationships, to these condensed consolidated financial statements.
Contract Manufacturing, Royalty and Other Revenue
Contract manufacturing, royalty and other revenue is summarized as follows:
 For the Three Months Ended June 30,For the Six Months Ended June 30,
(In millions)2026202520262025
Contract manufacturing revenue$232.4 $225.0 $469.6 $507.3 
Royalty and other revenue
10.0 19.6 19.7 30.6 
Total contract manufacturing, royalty and other revenue$242.4 $244.6 $489.3 $537.9 
Contract Manufacturing Revenue
Contract manufacturing revenue primarily reflects amounts earned under contract manufacturing agreements with our strategic customers and batches of LEQEMBI related to our collaboration with Eisai.
Royalty and Other Revenue
Royalty and other revenue primarily reflects royalty revenue on biosimilar products from our license arrangements with Samsung Bioepis and royalties we receive from net sales on products related to patents that we have out-licensed, including arrangements with Sobi that we inherited through our acquisition of Apellis.
For additional information on our arrangements with Samsung Bioepis, Eisai and Sobi, please read Note 18, Collaborative and Other Relationships, to these condensed consolidated financial statements.