v3.26.1
Revenues (Tables)
 6 Months Ended
Jun. 30, 2026
Revenue from Contract with Customer [Abstract]  
Revenues by product
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.
Analysis of change In reserves
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 
Total reserves included in consolidated balance sheets
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 
Revenues 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 
Other revenues
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