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ESMO 2025 – Datroway and Trodelvy face off in triple-negative breast

Both are heralded as a new first-line standard of care, but Datroway seems to have the edge.

Data with the rival TROP2 ADCs Datroway and Trodelvy mark a shift in the treatment paradigm in first-line triple-negative breast cancer, ESMO heard on Sunday. Both agents impressed, in the Tropion-Breast02 and Ascent-03 studies respectively, but the results suggest that Daiichi Sankyo/AstraZeneca's Datroway could have an edge over Gilead’s Trodelvy.Both agents demonstrated a statistically significant improvement on progression-free survival when compared against chemotherapy. Only Datroway also showed a benefit on overall survival, although Trodelvy’s Ascent-03 trial isn’t powered to test OS superiority – and in any case might be confounded by allowing control patients to progress to second-line Trodelvy on progression.Given similar PFS benefits, and the complications in comparing OS between trials, the toxicity profile of the compounds could become especially important, noted the ESMO discussant, Dana-Farber Cancer Institute’s Dr Ana Garrido-Castro.She added that the safety profile of Datroway “appears more favourable” than that of Trodelvy, with the former showing fewer grade 3 or higher adverse events. There were also six treatment-related deaths with Trodelvy, all being due to infection, versus none with Datroway.Cross-trial comparisonBoth Tropion-Breast02 and Ascent-03 enrolled patients who were ineligible for PD-(L)1 inhibitors, and the former also included patients without regulatory access. 60-70% of first-line TNBC patients aren’t candidates for checkpoint inhibitors.In Tropion-Breast02, median PFS was 10.8 months with Datroway, versus 5.6 months with investigator’s choice of chemo, equating to a 43% reduction in the risk of disease progression or death.In Ascent-03, which was simultaneously published in NEJM, mPFS was 9.7 months versus 6.9 months with chemo, equating to a 38% reduction in the risk of progression or death. Garrido-Castro noted that the larger absolute difference in mPFS seen in Tropion-Breast02, versus Ascent-03, might be down to the former enrolling higher-risk patients than the latter. Overall, she called the PFS benefit between the two trials “consistent”. Cross-trial comparison of Trodelvy and Datroway in first-line TNBC Ascent-03Tropion-Breast02RegimenTrodelvyChemoDatrowayChemomPFS9.7 mths6.9 mths10.8 mths5.6 mthsStatsHR=0.62; p<0.001HR=0.57; p<0.0001mOS21.5 mths20.2 mths23.7 mths18.7 mthsStatsHR=0.98 (37% maturity)HR=0.79; p=0.0291ORR48%46%63%29%mDoR12.2 mths7.2 mths12.3 mths7.1 mths≥Gr3 TRAEs61%53%33%29%Treatment-related deaths2%<1%0%0%Note: OS analysis was “descriptive” only in Ascent-03 & OS was co-primary endpoint in Tropion-Breast02. Source: ESMO 2025. Overall survival was a different story, however. This was a co-primary endpoint of Tropion-Breast02, which found a 21% reduction in the risk of death with Datroway versus chemo.There was no OS benefit in Ascent-03, with a reported hazard ratio of 0.98. However, OS was only a secondary endpoint of Ascent-03, the analysis was described as “descriptive”, and data were only 37% mature. No OS curve was presented at ESMO, but Gilead said it would continue to monitor OS, with further analysis planned.Ascent-03 allowed progressing control patients to cross over to second-line Trodelvy. Crossover to Datroway wasn't possible in Tropion-Breast02 because the Daiichi/Astra drug isn't approved for TNBC, though patients could of course drop out and receive Trodelvy off study.As for grade 3 or higher treatment-related adverse events, these were seen in 61% of Trodelvy-treated patients in Ascent-03, and in 33% of Datroway-treated patients in Tropion-Breast02. There was less neutropenia and GI toxicity with Datroway than with Trodelvy, noted Garrido-Castro. However, oral mucositis/stomatitis and ocular surface toxicity were seen with Datroway.There could be questions again about interstitial lung disease, a known issue with deruxtecan-containing ADCs like Datroway. One patient in the Datroway arm of Tropion-Breast02 had grade 3 pneumonitis and then died; however, the death itself was attributed to disease progression. This phenomenon has been seen before in Datroway studies.TNBC has an extremely poor prognosis, so ILD could be a risk worth taking for patients. And doctors could soon face a choice between two agents in the front line – which could be a nice problem to have in this underserved disease.
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Molecular Drug Targets