Datroway and Trodelvy's new breast cancer battle

After facing off at ESMO, the rival TROP2-targeting ADCs Datroway and Trodelvy could soon be going head-to-head in the first-line triple-negative breast cancer market. AstraZeneca and Daiichi revealed on Tuesday that Datroway has a June PDUFA date in PD-(L)1-ineligible disease, putting the drug slightly ahead of Gilead’s Trodelvy, which faces an FDA decision in the second half of 2026.

However, it wasn’t all good news, with Daiichi reporting several Datroway lung cancer setbacks on Friday. The partners have abandoned one phase 3 study, Tropion-Lung12, and results from a handful of trials have been delayed, including the key Avanzar study, which won’t now yield data until the second half of the year.

These issues were disclosed in Daiichi’s third-quarter presentation, and first reported by Fierce Biotech.

Avanzar delay

Avanzar, in first-line NSCLC, relies on an Astra in-house diagnostic to identify patients who might be especially susceptible to treatment with an anti-TROP2 ADC; as such, Astra and Daiichi are taking a different approach to their TROP2 rivals.

The trial is comparing Datroway plus Imfinzi and chemo, versus Keytruda plus chemo, and will primarily test PFS and OS – both in TROP2-positive patients, and in all comers.

Results from the study had once been expected in the second half of last year, but in July Astra noted that this had been pushed back to the first half of 2026. Now Daiichi has said that the results have been delayed further, until the second half of calendar year 2026.

The Japanese group also disclosed delays to two more first-line NSCLC studies, Tropion-Lung07 and 08. These are now expected to read out in the second half of fiscal 2026 (Daiichi’s financial year runs from April to March). Astra had previously guided to results in the first half of 2026.

Daiichi also said that in Tropion-Lung07 the partners have added PFS and OS in TROP2-positive patients as extra primary endpoints; the study had previously been evaluating the same endpoints, but only in all comers. This suggests that Astra's TROP2 assay is being employed here too.

Meanwhile, Tropion-Lung12 is a dead end. The study was enrolling patients with ctDNA-positive stage I NSCLC, and testing adjuvant Datroway alongside Astra’s anti-TIGIT x PD-1 MAb rilvegostomig, or rilvegostomig alone, versus chemo.

Daiichi said that recruitment had been stopped owing to “operational complexity”. The group added that there had been no new safety signals; Datroway has been linked with interstitial lung disease.

The writing was on the wall for Tropion-Lung12 when, in January, recruitment was stopped at 24 patients, versus a planned 660, and the trial's status changed from “recruiting” to “active, not recruiting”.

Datroway delays and discontinuations in NSCLC

Source: OncologyPipeline & Daiichi Q3 2025 presentation.

At least in TNBC it looks like better news for Datroway. The partners are expecting an approval decision by 2 June in patients ineligible for or unable to receive PD-(L)1 inhibitors, based on Tropion-Breast02.

At ESMO, the Astra/Daiichi drug looked to have an edge over Trodelvy, which prevailed in its own PD-(L)1-ineligible study, Ascent-03. Gilead said last October that it had filed Trodelvy with the FDA based on that trial, but hasn’t provided a PDUFA date, only saying that a decision is expected in the second half.

That group also expects a verdict around the same time on Trodelvy in PD-L1-positive first-line TNBC, based on Ascent-04, which was presented at ASCO. Datroway’s analogous study, Tropion-Breast05, isn’t expected to yield data until after 2026, according to Astra’s third-quarter earnings presentation; the company, which reports its full-year results on 10 February, had previously expected results in 2026.

Datroway vs Trodelvy in first-line TNBC

Note: *at 37% maturity. Source: OncologyPipeline.