ChemoCentryx: $3.9 Billion for TAVNEOSThin moat

Amgen (AMGN) — moat facet

Amgen paid $3.9 billion for TAVNEOS, which was growing well until the FDA proposed in 2026 to withdraw its approval.

Amgen bought ChemoCentryx in October 2022 for $52.00 a share in cash, a total consideration of $3.9 billion1. It got TAVNEOS, approved in October 2021 for severe active ANCA-associated vasculitis alongside standard therapy, which had been on the market for a year when Amgen bought it2. TAVNEOS sold $21 million in 2022, $134 million in 2023, $283 million in 2024 and $459 million in 202534, and $269 million in the first half of 20265.

TAVNEOS sales ($M)212022134202328320244592025269H1 2026Amgen results releases FY2023, FY2025 and 2026; bought for $3.9bn in 2022
Growing well until the regulator stepped in.

As a business it was working. Sales were growing and the drug's American patent runs to January 20346. It is the smallest of Amgen's large purchases and the one where the growth curve most resembled the plan.

Then the regulator reversed. The FDA asked Amgen on 16 January 2026 to withdraw TAVNEOS voluntarily, and Amgen refused on 28 January7. On 27 April the FDA's drug centre proposed to withdraw the approval, a hearing was requested on 1 June, and Amgen submitted its materials on 23 July8. The drug stays on sale while the proceeding runs.

The accounting exposure is precise. The TAVNEOS intangible had a carrying value of $2.4 billion at 30 June 2026, $2.3 billion of it related to the United States9. If approval is withdrawn, most of that would be written off.

Amgen is not conceding. In the second-quarter 2026 release it said it continues to engage with the FDA and believes that TAVNEOS demonstrates clinical effectiveness and a favorable benefit-risk profile10, and the drug's sales rose 36% in the quarter, driven by volume growth11. Doctors, at least, are still prescribing it.

This is the risk that no amount of scale removes: a regulator deciding that the evidence for a drug is not sufficient. The outcome of the hearing is the event to watch. A decision to withdraw would turn a $3.9 billion purchase into a write-off of about $2.4 billion, and TAVNEOS sales, $150 million in the second quarter of 202612, would go to zero in America.

Moat trajectory: Narrowing

FDA withdrawal proposal April 2026; hearing pending.

The number that tests this moat
Reported
TAVNEOS sales, latest quarter
$150M (Q2 2026)

Sales during the FDA proceeding; a withdrawal would end the American business and write off most of the $2.4bn intangible.

Source: Amgen Q2 2026 results release ↗
⚠ Threats to the moat
⚠ THREAT 01
The FDA's Withdrawal Proposal
The FDA has proposed withdrawing TAVNEOS, and $2.4 billion of intangible assets depends on the hearing.
References
  1. ReportedAmgen bought ChemoCentryx in October 2022 for $52.00 a share in cash, a total consideration of $3.9 billion.
    Amgen Form 10-K for fiscal 2023 - the Horizon and ChemoCentryx acquisitions, their purchase-price allocation and the debt that funded them; sales deductions for 2021-2023. — FY2023 · publ. February 2024 · source ↗
  2. ReportedIt got TAVNEOS, approved in October 2021 for severe active ANCA-associated vasculitis alongside standard therapy, which had been on the market for a year when Amgen bought it.
    Amgen Form 10-K for fiscal 2025 - Item 1 business: products, collaborations, staff and pipeline. — FY2025 · publ. 13 February 2026 · source ↗
  3. ReportedTAVNEOS sold $21 million in 2022, $134 million in 2023, $283 million in 2024 and $459 million in 2025, and $269 million in the first half of 2026.
    Amgen fourth-quarter and full-year 2023 results release, Form 8-K exhibit 99.1 - product sales for 2022-2023. — FY2023 · publ. February 2024 · source ↗
  4. ReportedTAVNEOS sold $21 million in 2022, $134 million in 2023, $283 million in 2024 and $459 million in 2025, and $269 million in the first half of 2026.
    Amgen fourth-quarter and full-year 2025 results release, Form 8-K exhibit 99.1 - product sales for 2024-2025, non-GAAP EPS and 2026 guidance. — FY2025 · publ. 3 February 2026 · source ↗
  5. Moat Explorer calcTAVNEOS sold $21 million in 2022, $134 million in 2023, $283 million in 2024 and $459 million in 2025, and $269 million in the first half of 2026.
    Moat Explorer calculation from Amgen's reported product sales and financial statements ($ millions unless stated). Sales deductions: 2019 rebates 6,825 + chargebacks 7,090 + other 1,292 = 15,207; 2025 21,697 + 16,988 + 3,298 = 41,983; 41,983 / 35,148 = 1.19 times net product sales; implied gross product sales 35,148 + 41,983 = 77,131. Growth 2019-2025: deductions 41,983 / 15,207 = 2.76 times; net product sales 35,148 / 22,204 = 1.58 times (up 58%); rebates 21,697 / 6,825 = 3.18 times; chargebacks 16,988 / 7,090 = 2.4 times. Wholesalers 2025 gross: 26,253 + 20,986 + 12,562 = 59,801; 59,801 / 36,751 = 1.63 times total revenues; McKesson 26,253 / 36,751 = 71%. ENBREL: 2,226 / 5,433 - 1 = -59%; share of product sales 5,226 / 22,204 = 23.5% (2019), 2,226 / 35,148 = 6.3% (2025). ENBREL + Otezla 2025: 2,226 + 2,265 = 4,491; 4,491 / 36,751 = 12%. Otezla sales 2020-2025: 2,195 + 2,249 + 2,288 + 2,188 + 2,126 + 2,265 = 13,311; impairment 1,200 / 13,400 = 9%. Horizon products: 2023 448 + 272 + 65 + 164 = 949; 2024 1,851 + 1,185 + 379 + 758 = 4,173; 2025 1,903 + 1,340 + 655 + 719 = 4,617, 4,617 / 27,800 = 16.6%; Q2 2026 576 + 400 + 335 + 149 = 1,460, x4 = 5,840. TEPEZZA + KRYSTEXXA 2025 1,903 + 1,340 = 3,243; KRYSTEXXA 1,340 / 1,185 - 1 = 13.1%; TEPEZZA 1,903 / 1,851 - 1 = 2.8%; UPLIZNA 655 / 379 - 1 = 72.8%; H1 2026 262 + 335 = 597; ultra-rare 719 / 758 - 1 = -5.1%; UPLIZNA + ultra-rare 655 + 719 = 1,374. TAVNEOS H1 2026 119 + 150 = 269. Acquisitions: 13.4 + 3.9 + 27.8 = 45.1 bn; acquired products 2025 2,265 + 459 + 4,617 = 7,341, 7,341 / 36,751 = 20%. Interest 2,755 / 9,080 = 30%. Net debt 30 June 2026: 57.3 - 13.989 = 43.3 bn. Goodwill + intangibles 18,680 + 22,276 = 40,956, 40,956 / 90,586 = 45%. EPS gap 21.84 - 14.23 = 7.61. R&D 7,272 / 4,784 - 1 = 52%; 7,272 / 36,751 = 19.8%. Growth drivers 2025: Repatha 3,016 + EVENITY 2,100 + TEZSPIRE 1,478 + BLINCYTO 1,559 = 8,153 (2024: 2,222 + 1,563 + 972 + 1,216 = 5,973; 2023: 1,635 + 1,160 + 567 + 861 = 4,223; 2021: 1,117 + 530 + 0 + 472 = 2,119; 2019: 661 + 189 + 0 + 312 = 1,162); 8,153 / 5,973 - 1 = 36.5%, about 37%; 8,153 / 36,751 = 22%. Repatha 3,016 / 661 = 4.6 times, 3,016 / 2,222 - 1 = 36%; EVENITY 2,100 / 189 = 11 times; BLINCYTO 1,559 / 312 = 5.0 times. KYPROLIS 1,412 / 1,503 - 1 = -6%; KYPROLIS + Nplate 1,412 + 1,524 = 2,936, 2,936 / 6,660 = 44%; BLINCYTO + IMDELLTRA 1,559 + 627 = 2,186; Q2 2026 472 + 288 = 760. IMDELLTRA run rate 288 x 4 = 1,152, 1,152 / 6,498 = 18%. Biosimilars: 2025 AMJEVITA 597 + PAVBLU 700 + WEZLANA 273 + MVASI 771 + in other products 683 = 3,024; 3,024 / 35,148 = 8.6% of product sales; 3,024 / 36,751 = 8.2% of total revenues; PAVBLU 700 / 3,024 = 23%; AMJEVITA 597 / 761 - 1 = -22%; band 2022 1,831 / 2,177 - 1 = -16%; in other products 683 / 667 - 1 = 2%; WEZLANA and other biosimilars added (273 - 27) + (683 - 667) = 262; Q2 2026 155 + 287 + 61 + 153 + 199 = 855; Q2 2025 133 + 130 + 35 + 191 + 172 = 661; 855 / 661 - 1 = 29%; shares of total revenues 568 / 23,362 = 2.4% (2019), 2,177 / 25,979 = 8.4% (2021), 1,916 / 28,190 = 6.8% (2023). Bands 2025: general medicine and bone 3,016 + 2,100 + 4,414 + 2,084 = 11,614 (31.6%); inflammation and rare disease 2,226 + 2,265 + 1,478 + 1,903 + 1,340 + 655 + 459 + 719 = 11,045 (30.1%); oncology 1,559 + 627 + 1,175 + 1,412 + 363 + 1,524 = 6,660 (18.1%); biosimilars 3,024 (8.2%); established and other 1,389 + 435 + 353 + (1,311 - 683 = 628) + 1,603 = 4,408 (12.0%); total 36,751. 2019 bands 5,457; 5,404; 2,895; 568; 9,038; total 23,362. General medicine 11,614 / 5,457 = 2.1 times, 11,614 / 10,384 - 1 = 11.8%; inflammation 2020 7,191, 2024 10,870 / 7,535 - 1 = 44%, 2025 11,045 / 10,870 - 1 = 1.6%, non-ENBREL-Otezla 11,045 - 4,491 = 6,554; oncology 6,660 / 2,895 = 2.3 times, 6,660 / 5,685 - 1 = 17.2%; established 4,408 / 9,038 = 0.49. Q2 bands 2026 vs 2025: general medicine 953 + 714 + 759 + 352 = 2,778 vs 696 + 518 + 1,122 + 532 = 2,868, down 3%; Repatha + EVENITY 1,667 vs 1,214; denosumab 1,111 vs 1,654, down 33%; inflammation 3,167 vs 604 + 618 + 342 + 505 + 349 + 176 + 110 + 183 = 2,887, up 9.7%; oncology 1,953 vs 384 + 134 + 305 + 378 + 90 + 369 = 1,660, up 17.7%; established and other 632 + (351 - 199) + 517 = 1,301 vs 359 + 82 + 92 + (334 - 172) + 408 = 1,103, up 18%. Denosumab 2025 4,414 + 2,084 = 6,498, 6,498 / 36,751 = 17.7%; Q1 2026 727 + 411 = 1,138; H1 2026 1,486 + 763 = 2,249 vs 2,221 + 1,098 = 3,319. Neulasta 435 / 4,534 - 1 = -90%. Geography: US 25,656 / 35,148 = 73%; rest of world 9,492 / 35,148 = 27.0%; Q2 2026 2,547 / 9,537 = 26.7%; AMJEVITA 129 / 155 = 83.2%; Aranesp 258 / 352 = 73.3%; ENBREL 6 / 580 = 1.0%. Novartis-facing 2025 3,016 + 2,265 + 2,226 + 1,524 + 1,478 = 10,509, 10,509 / 36,751 = 29%. Other revenues 1,603 / 36,751 = 4.4%. Receivables 9,570 / 6,782 - 1 = 41%. Guidance midpoints: (37.0 + 38.4) / 2 = 37.7; (37.1 + 38.5) / 2 = 37.8; (38.2 + 39.4) / 2 = 38.8; non-GAAP EPS (22.30 + 23.50) / 2 = 22.90. IRS: 3.6 + 5.1 + 2.0 = 10.7 bn before interest; offsets 0.9 + 2.2 = 3.1 bn; 10.7 / 7.711 = 1.4 times 2025 net income; 10.7 / 224.15 = 4.8% of market value. Trailing free cash flow 8,100 - 2,891 + 4,966 = 10,175; 10,175 / 224,150 = 4.5%. Shares 538.8 / 629.6 - 1 = -14%. Gross margin (total revenues - cost of sales) / total revenues: (28,190 - 8,451) / 28,190 = 70.0% (2023); (33,424 - 12,858) / 33,424 = 61.5% (2024); (36,751 - 12,037) / 36,751 = 67.2% (2025). Pre-tax income 2025 7,711 + 1,265 = 8,976. Total revenues 36,751 / 21,662 = 1.70 times 2015. Market value 224.15 / 176.25 - 1 = 27% in 2026; added 224.15 - 176.25 = 47.9 bn against 176.25 - 122.45 = 53.8 bn in 2015-2025. Trailing net income 7,711 - 3,162 + 4,194 = 8,743; trailing revenue 36,751 - 17,328 + 18,672 = 38,095 - product and band totals, growth and sales deductions. — 2015-2026 · publ. September 2026 · source ↗
    Method: Arithmetic on figures reported in Amgen's Forms 10-K, 10-Q, results releases and market data; operands shown in the source line.
  6. ReportedSales were growing and the drug's American patent runs to January 2034.
    Amgen Form 10-K for fiscal 2025 - Item 1 patents, biosimilars and competitors. — FY2025 · publ. 13 February 2026 · source ↗
  7. ReportedThe FDA asked Amgen on 16 January 2026 to withdraw TAVNEOS voluntarily, and Amgen refused on 28 January.
    Amgen Form 10-K for fiscal 2025 - Item 1A risk factors, government pricing and legal proceedings including the IRS dispute. — FY2025 · publ. 13 February 2026 · source ↗
  8. ReportedOn 27 April the FDA's drug centre proposed to withdraw the approval, a hearing was requested on 1 June, and Amgen submitted its materials on 23 July.
    Amgen Form 10-Q for the quarter ended 30 June 2026 - product sales, the TAVNEOS proceeding, the IRS dispute, the BeOne stake and the balance sheet. — Q2 2026 · publ. 5 August 2026 · source ↗
  9. ReportedThe TAVNEOS intangible had a carrying value of $2.4 billion at 30 June 2026, $2.3 billion of it related to the United States.
    Amgen Form 10-Q for the quarter ended 30 June 2026 - product sales, the TAVNEOS proceeding, the IRS dispute, the BeOne stake and the balance sheet. — Q2 2026 · publ. 5 August 2026 · source ↗
  10. ReportedIn the second-quarter 2026 release it said it continues to engage with the FDA and believes that TAVNEOS demonstrates clinical effectiveness and a favorable benefit-risk profile, and the drug's sales rose 36% in the quarter, driven by volume growth.
    Amgen second-quarter 2026 results release, Form 8-K exhibit 99.1 - product sales performance: inflammation, rare disease and established products, and sales by region. — Q2 2026 · publ. 4 August 2026 · source ↗
  11. ReportedIn the second-quarter 2026 release it said it continues to engage with the FDA and believes that TAVNEOS demonstrates clinical effectiveness and a favorable benefit-risk profile, and the drug's sales rose 36% in the quarter, driven by volume growth.
    Amgen second-quarter 2026 results release, Form 8-K exhibit 99.1 - product sales performance: inflammation, rare disease and established products, and sales by region. — Q2 2026 · publ. 4 August 2026 · source ↗
  12. ReportedA decision to withdraw would turn a $3.9 billion purchase into a write-off of about $2.4 billion, and TAVNEOS sales, $150 million in the second quarter of 2026, would go to zero in America.
    Amgen second-quarter 2026 results release, Form 8-K exhibit 99.1 - product sales performance: inflammation, rare disease and established products, and sales by region. — Q2 2026 · publ. 4 August 2026 · source ↗
Sources
Generated September 28, 2026