ESMO Congress 2026

Disitamab vedotin (RC48) is a HER2-targeting antibody-drug conjugate in which hertuzumab is linked via a cleavable linker to the cytotoxic payload MMAE ^[2]. Its published evidence base: in June 2021 it was approved in China for HER2-overexpressing (IHC2+ or 3+) locally advanced or metastatic gastric/gastroesophageal junction adenocarcinoma after at least two systemic chemotherapy regimens ^[4]; it was recorded by the 2022 annual antibodies-to-watch review as one of the novel antibody therapeutics approved in China that year ^[1], and has been described as the third approved HER2-directed ADC ^[6]. In urothelial carcinoma, published data come from a combined analysis of two single-arm phase II studies, RC48-C005 and RC48-C009: 107 patients with HER2-positive (IHC 3+ or 2+) locally advanced or metastatic urothelial carcinoma previously treated with chemotherapy received DV 2 mg/kg once every two weeks, with a BIRC-confirmed ORR of 50.5% and consistent results in prespecified subgroups including liver metastasis and prior anti-PD-(L)1 therapy ^[3].

What was reported at ESMO 2026 moves this ADC into earlier lines and the perioperative setting. GUARD-01 (Phase II) evaluated neoadjuvant DV plus gemcitabine in HER2-positive muscle-invasive bladder cancer (MIBC): pCR was 62.5% (15/24), 3-year EFS after cystectomy was 78.1%, the field post called the long-term outcomes promising, and Phase III GUARD-02 is ongoing. WUTSUP-02 (Phase II, n=42) evaluated neoadjuvant DV plus perioperative tislelizumab in high-risk, non-metastatic upper tract urothelial carcinoma (UTUC), where 81% were HER2-positive; the field post described promising antitumor activity and suggested that higher HER2 expression may predict response, without disclosing specific efficacy numbers.

The site news independently reported that RemeGen (Rongchang Bio) presented three studies at ESMO 2026—advanced EMPD, neoadjuvant therapy in MIBC, and HER2 detection in bladder CIS—corroborating the MIBC neoadjuvant thread from the field posts, though it gave no GUARD-01 readouts; what the news added was an indication not covered by the field posts: in the Formula-10 study, 25 patients met the imaging-based evaluability criteria, with an ORR of 88%, DCR of 100%, median PFS of 14.23 months, and grade 3 or higher treatment-related adverse events in 29.6%.

Relative to what was already known, the step forward is the shift to earlier settings and combination strategies: prior evidence was confined to monotherapy in treated advanced or metastatic urothelial carcinoma ^[3], whereas GUARD-01 moved DV into neoadjuvant non-metastatic MIBC combined with gemcitabine, delivered pCR and 3-year EFS signals from a single-arm phase II, and has Phase III GUARD-02 carrying the strategy forward; WUTSUP-02 combined DV with the PD-1 antibody tislelizumab in the perioperative UTUC setting and proposed HER2 expression level as a possible predictive factor. The limitations are equally clear: both are single-arm phase II studies, pCR was assessed in only 24 patients in GUARD-01, specific efficacy numbers for WUTSUP-02 were not disclosed, and the predictive value of HER2 expression and long-term benefit await confirmation in larger samples and phase III data.