By Fineline Cube Daiichi Sankyo (TYO: 4568) announced that Raludotatug Deruxtecan (R‑DXd, DS‑6000a), a first‑in‑class CDH6‑targeted antibody‑drug conjugate (ADC), has received Breakthrough Therapy Designation (BTD) from the U.S. FDA for adult patients with platinum‑resistant epithelial ovarian, primary peritoneal, or fallopian tube cancer expressing CDH6 who have received prior bevacizumab therapy.
Regulatory Milestone & Clinical Context
| Item | Detail |
|---|---|
| Company | Daiichi Sankyo (TYO: 4568) |
| Drug | Raludotatug Deruxtecan (R‑DXd, DS‑6000a) |
| Designation | Breakthrough Therapy Designation (FDA) |
| Indication | Platinum‑resistant ovarian, peritoneal, or fallopian tube cancer (CDH6‑positive) |
| Patient Population | Post‑bevacizumab, advanced stage |
| Mechanism | CDH6‑targeted ADC (anti‑CDH6 IgG1, peptide linker, topoisomerase I inhibitor) |
| Market Status | No approved CDH6‑targeted therapies currently exist |
Drug Profile & Innovation
- First‑in‑Class: R‑DXd is the only ADC specifically targeting CDH6 (Cadherin‑6), a cell adhesion protein overexpressed in 65–85% of ovarian cancers
- ADC Technology: Humanized anti‑CDH6 IgG1 monoclonal antibody, enzymatically cleavable peptide linker, and potent topoisomerase I inhibitor payload
- Clinical Rationale: CDH6 overexpression correlates with poor prognosis, creating high unmet need in platinum‑resistant disease
- Differentiation: Novel target allows for precise tumor cell killing while sparing healthy tissue
Partnership Structure with Merck
- Global Collaboration: Daiichi Sankyo and Merck & Co. (MSD outside US/Canada) entered worldwide partnership in October 2023 for three ADCs: Patritumab deruxtecan, Ifinatamab deruxtecan, and Raludotatug deruxtecan
- Regional Rights: Daiichi Sankyo holds exclusive rights in Japan; Merck leads ex‑Japan development/commercialization
- Manufacturing: Daiichi Sankyo fully responsible for ADC manufacturing and supply
- Expanded Agreement: In August 2024, collaboration added MK‑6070 (bispecific), with Merck holding Japan rights and manufacturing responsibility
Market Impact & Commercial Outlook
- Ovarian Cancer Market: Global market valued at $2.5 billion in 2025; platinum‑resistant segment represents 30% of patients with limited treatment options
- Revenue Potential: Analysts project $3–5 billion peak sales potential for R‑DXd in ovarian cancer if approved, based on CDH6 prevalence and lack of competition
- Strategic Value: BTD accelerates FDA review timeline, potential for 2027 NDA submission and 2028 launch
- Pipeline Leverage: Validates Daiichi Sankyo’s ADC platform, strengthening position in ADC leadership rivalry with AstraZeneca/Daiichi’s Enhertu franchise
- Next Steps: Phase II trial readout expected mid‑2026; BTD enables rolling review and priority FDA engagement
Forward‑Looking Statements
This brief includes forward‑looking statements regarding clinical development timelines, regulatory pathways, and revenue projections for Raludotatug Deruxtecan. Actual results may differ due to clinical trial outcomes, competitive developments, and FDA review processes.-Fineline Info & Tech