Pharma BD Deal Intelligence
Merck's $600M-upfront, ~$4.2B collaboration with Seagen paired ladiratuzumab vedotin with Keytruda in triple-negative breast cancer while handing Merck ex-U.S. rights to TUKYSA—though Seagen scrapped ladiratuzumab vedotin in 2022 after newer ADCs raised the efficacy bar, leaving TUKYSA as the deal's lasting asset.
In September 2019 Merck & Co. and Seattle Genetics (later Seagen) entered two strategic oncology collaborations, finalized and announced September 14, 2020. (1) Global co-development and co-commercialization of ladiratuzumab vedotin (LV), Seagen's investigational anti-LIV-1 antibody-drug conjugate, in combination with Keytruda for triple-negative breast cancer and other solid tumors: $600M upfront, a $1.0B Merck equity investment (5.0M shares at $200), and up to $2.6B in milestones ($850M development + $1.75B sales) — a ~$4.2B headline — on a 50:50 cost/profit-share basis. (2) An exclusive license granting Merck commercialization rights to TUKYSA (tucatinib), Seagen's HER2 tyrosine kinase inhibitor, in Asia, the Middle East, Latin America and other regions outside the U.S., Canada and Europe: $125M upfront, up to $65M in milestones, $85M prepaid R&D and tiered royalties. Seagen deprioritized and discontinued LV in 2022, citing a higher efficacy threshold set by newer ADCs; Pfizer subsequently acquired Seagen for ~$43B in 2023.
310K US cases/yr · $12.0B Global ADC Market (breast cancer, 2024)
Breast cancer is the most common cancer among U.S. women, with NCI SEER estimating approximately 310,000 new invasive cases and 42,000 deaths per year. Subtyping by hormone receptor (ER/PR) and HER2 status defines treatment: HR+/HER2- (most common), HER2+ (~15-20%), and triple-negative (~10-15%). Risk factors include age, family history, BRCA1/2 and other germline mutations, early menarche, late menopause, nulliparity, dense breasts, and prior chest radiation. Screening mammography has reduced mortality in average-risk women; higher-risk women are considered for supplemental MRI and earlier screening. Diagnosis combines imaging with core-needle biopsy and pathology including receptor testing. Staging follows AJCC TNM with biomarker incorporation. Treatment is stage- and subtype-specific: surgery (lumpectomy or mastectomy) with sentinel lymph node biopsy, radiotherapy, endocrine therapy for HR+ disease, HER2-directed therapy (trastuzumab, pertuzumab, T-DM1, trastuzumab deruxtecan) for HER2+ or HER2-low disease, chemotherapy, CDK4/6 inhibitors and PI3K/AKT pathway inhibitors, PARP inhibitors for germline BRCA1/2 carriers, and immunotherapy in select triple-negative settings. Metastatic disease remains incurable but increasingly chronic.
The breast cancer ADC landscape has been reshaped by Enhertu's dominance. Trodelvy (Gilead) targets Trop-2 in TNBC. Padcev (Pfizer/Seagen) is focused on bladder cancer. The LIV-1 target proved less productive than hoped. Pfizer inherited the Seagen partnership portfolio and prioritized differently.
Merck paid $600M upfront + $1B equity for ladiratuzumab vedotin co-development with Keytruda.
Seagen deprioritized LV citing higher efficacy threshold from newer ADCs. Program discontinued.
LV discontinued. Seagen later acquired by Pfizer for $43B (2023), superseding remaining collaboration.
| Deal | Year | Value | Outcome |
|---|---|---|---|
| Merck & Co. Inc. / Seagen Inc. (this deal) | 2019 | $4.2B | 48 |
| Merck & Co. Inc. / Acceleron Pharma Inc. | 2021 | $11.5B | 90 |
| Merck & Co. Inc. / Peloton Therapeutics Inc. | 2019 | $2.2B | 88 |
| Merck & Co. Inc. / AstraZeneca PLC | 2017 | $8.5B | 87 |
| Merck & Co. Inc. / Moderna, Inc. | 2022 | $250M | 86 |
| Merck & Co. Inc. / Moderna, Inc. | 2016 | $250M | 84 |
| Merck & Co. Inc. / Eisai Co., Ltd. | 2018 | $5.8B | 83 |
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More: 2019 deals · Merck & Co. Inc. deals · Oncology deals