BeOne Medicines Ltd. ("BeOne") (NASDAQ:ONC, HKEX: 06160, SSE: 688235))), a global oncology company, today announced new data from its solid tumor pipeline being presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting (May 29–June 2, Chicago). These data underscore the significant acceleration across the Company's high-priority breast, gynecologic and gastrointestinal (GI) cancer development programs.

Data from three differentiated BeOne pipeline assets will be presented, including:

  • CDK4 inhibitor (BGB-43395) (poster presentation): First disclosure of anti-tumor activity in first-line (1L) HR+/HER2- metastatic breast cancer.
  • B7-H4 ADC (BG‑C9074) (rapid oral presentation): Phase 1 dose-escalation and safety expansion data in advanced solid tumors.
  • GPC3x4-1BB (BGB-B2033) bispecific antibody (rapid oral presentation): First clinical data in advanced solid tumors, including hepatocellular carcinoma (HCC), the most common type of liver cancer.

Mark Lanasa, M.D., Ph.D., Chief Medical Officer, Solid Tumors, BeOne Medicines, said: "2026 is an inflection year for BeOne's solid tumor portfolio, marked by the encouraging data we are presenting at ASCO combined with upcoming readouts at other major congresses. These programs validate our strategy of pairing the right biology with the right modality, and support advancing several assets in different indications into pivotal trials in 2026."

Selective CDK4 inhibitor shows promising efficacy and differentiated safety in first-line breast cancer (Poster Presentation: 180; June 1, 2026, 1:30 PM-4:30 PM CDT)

BeOne will present data about its highly selective CDK4 inhibitor, BGB-43395, in 1L HR+/HER2- metastatic breast cancer, in combination with letrozole, showing promising anti-tumor activity and a favorable safety profile, characterized by infrequent low-grade hematologic toxicities and manageable GI events, which were further mitigated when administered with food. Highlights include:

  • The 240 mg dose of BGB-43395 plus letrozole resulted in a confirmed overall response rate (ORR) of 68.4% (95% CI: 43.4–87.4) and unconfirmed ORR of 73.7% (95% CI: 48.8-90.9).
  • The 400 mg dose plus letrozole resulted in a confirmed ORR of 63.2% (95% CI: 38.4–83.7) and unconfirmed ORR of 73.7% (95% CI: 48.8-90.9).
  • Low levels of hematologic treatment-related adverse events (TRAEs) with Grade ≥3 neutropenia reported in 5.3% of patients at the 240 mg dose level and 0% at 400 mg, as well as low frequency of fatigue and asthenia; supports profile and validates the molecule's high selectivity for CDK4.
  • GI TRAEs were mitigated when administered with food, all of which were Grade 1.
  • Median study follow-up was 12.5 (range, 3.1-15.2) months, 12.4 (range, 8.0-15.0) months, and 10.8 (range, 3.2-12.9) months for the 240 mg, 400 mg, and 600 mg dose groups, respectively.

These compelling safety and efficacy findings support the rationale to initiate a global, randomized Phase 3 clinical trial with BGB-43395 in combination with letrozole in 1L HR+/HER2- metastatic breast cancer. The trial, KANDELA-302 (NCT07492641), will begin enrolling patients this month.

B7-H4 ADC demonstrates encouraging efficacy supporting advancement in ovarian cancer (Rapid Oral Abstract: 3013; June 2, 2026, 9:45-11:15 AM CDT)

Data at ASCO from BeOne's B7‑H4-targeting antibody-drug conjugate (ADC), BG‑C9074, include results from Phase 1 dose‑escalation and safety‑expansion cohorts, demonstrating a combination of early efficacy signals and a favorable tolerability profile. Highlights include:

  • At doses under consideration for future development, confirmed ORR of 45.5% and unconfirmed ORR of 54.5% in ovarian cancer (OC), and 40.0% in triple-negative breast cancer, with median study follow-up of 6.6 (range, 0.3-20.8) months.
  • Anti-tumor activity demonstrated in OC regardless of B7-H4 expression level.
  • Treatment was generally well tolerated with low rates of discontinuation at <5%; 31.5% of patients experienced Grade ≥3 TRAEs, with no Grade ≥3 nausea at 6 mg/kg adjusted ideal body weight (AIBW) and 1.2% at 8 mg/kg AIBW. Grade ≥3 neutropenia rates were 14.8% at 6 mg/kg AIBW and 34.6% at 8 mg/kg AIBW.
  • AIBW-based dosing used in the ongoing phase 1 study of BG-C9074 effectively reduced pharmacokinetic variability compared with total body weight dosing, as presented in a separate abstract (Poster 166) at ASCO.

These results support continued advancement of the BG‑C9074 development program, with efforts focused on early‑line OC and additional B7‑H4-expressing tumor types.

Potential first-in-class GPC3x4-1BB bispecific demonstrates unprecedented anti-tumor activity in heavily pre-treated HCC patients (Rapid Oral Abstract: 3016; June 2, 2026, 9:45-11:15 AM CDT)

The first clinical data (Phase 1a) for BGB-B2033, a GPC3x4-1BB bispecific antibody, will be presented in a rapid oral session highlighting the first-in-class potential of this program in advanced solid tumors, including heavily pre-treated HCC. BGB-B2033 was rationally designed to target GPC3-expressing tumors, a protein commonly expressed in HCC, the sixth most prevalent cancer and third leading cause of cancer death worldwide,1 with five-year survival rates of only approximately 20%.