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v3.25.1

Revenues - Revenues by product (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Disaggregation of Revenue [Line Items] |  |
Total revenue | $ 2,431.0 | $ 2,290.5
Product revenue, net |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 1,726.5 | 1,711.9
Product revenue, net | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 753.8 | 746.1
Product revenue, net | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 972.7 | 965.8
MS Product Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 953.0 | 1,075.9
MS Product Revenues | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 490.4 | 503.2
MS Product Revenues | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 462.6 | 572.7
Fumarate |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 344.9 | 381.8
Fumarate | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 156.9 | 149.6
Fumarate | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 188.0 | 232.2
TECFIDERA |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 206.1 | 254.3
TECFIDERA | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 39.8 | 43.7
TECFIDERA | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 166.3 | 210.6
VUMERITY |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 138.8 | 127.5
VUMERITY | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 117.1 | 105.9
VUMERITY | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 21.7 | 21.6
Interferon |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 226.3 | 243.6
Interferon | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 132.7 | 139.8
Interferon | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 93.6 | 103.8
AVONEX |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 166.8 | 178.5
AVONEX | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 108.6 | 111.2
AVONEX | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 58.2 | 67.3
PLEGRIDY |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 59.5 | 65.1
PLEGRIDY | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 24.1 | 28.6
PLEGRIDY | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 35.4 | 36.5
TYSABRI |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 381.5 | 431.3
TYSABRI | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 200.8 | 213.8
TYSABRI | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 180.7 | 217.5
FAMPYRA |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.3 | 19.2
FAMPYRA | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
FAMPYRA | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.3 | 19.2
Rare Disease Product Revenue |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 563.3 | 423.9
Rare Disease Product Revenue | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 231.0 | 225.9
Rare Disease Product Revenue | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 332.3 | 198.0
QALSODY |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 15.5 | 4.6
QALSODY | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 7.5 | 4.4
QALSODY | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 8.0 | 0.2
SPINRAZA |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 423.9 | 341.3
SPINRAZA | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 154.4 | 148.5
SPINRAZA | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 269.5 | 192.8
SKYCLARYS |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 123.9 | 78.0
SKYCLARYS | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 69.1 | 73.0
SKYCLARYS | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 54.8 | 5.0
Biosimilars |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 180.8 | 196.9
Biosimilars | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 4.3 | 3.7
Biosimilars | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 176.5 | 193.2
BENEPALI |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 111.3 | 118.7
BENEPALI | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
BENEPALI | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 111.3 | 118.7
IMRALDI |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 47.4 | 54.8
IMRALDI | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
IMRALDI | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 47.4 | 54.8
FLIXABI |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 13.1 | 17.8
FLIXABI | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
FLIXABI | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 13.1 | 17.8
BYOOVIZ |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 8.9 | 5.6
BYOOVIZ | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 4.2 | 3.7
BYOOVIZ | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 4.7 | 1.9
TOFIDENCE |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.1 | 0.0
TOFIDENCE | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.1 | 0.0
TOFIDENCE | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
Other |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 29.4 | 15.2
Other | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 28.1 | 13.3
Other | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 1.3 | 1.9
ZURZUVAE |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 27.7 | 12.4
ZURZUVAE | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 27.7 | 12.4
ZURZUVAE | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.0 | 0.0
FUMADERM And ADUHELM |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 1.7 | 2.8
FUMADERM And ADUHELM | U.S. |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | 0.4 | 0.9
FUMADERM And ADUHELM | Rest of World |  |
Disaggregation of Revenue [Line Items] |  |
Total revenue | $ 1.3 | $ 1.9

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