EU backs Tevimbra's stomach restriction – and then some
While BeiGene awaits US Tevimbra approvals for front-line oesophageal squamous cell and gastric/gastroesophageal junction cancers, it has a pretty good idea that the FDA will limit these to PD-L1-expressing patients. That view has been more than endorsed by the EU regulator, which has just greenlit Tevimbra chemo combos in these two settings, backed by the Rationale-306 and 305 trials respectively, in patients whose cancers express PD-L1 with a tumour area positivity (TAP) score of ≥5%. The precise PD-L1 cutoff the FDA will apply is unknown. The issue was debated at length during a September adcom, as a result of which Tevimbra missed its July 2024 PDUFA date for the Rationale-306 indication (the other use has a December 2024 PDUFA date). The adcom's upshot was that PD-(L)1 drug approvals in these cancers should be restricted to PD-L1-expressers – but at 1% rather than the 5% the EMA has opted for. Matters aren't helped by the fact that Rationale-306 subgroup data provided analysis for neither cutoff, but rather for ≥10% PD-L1 expression. And, to complicate things further, TAP is just one of three PD-L1 scoring methods being used, with no agreement on future uniformity.
Selected Tevimbra + chemo approvals
Trial | 1st-line setting | HR for OS in all-comers | HR for OS in PD-L1 subgroup | EU status | US status |
---|---|---|---|---|---|
Rationale-306 | Oesophageal squamous cell carcinoma | 0.66 | 0.62 in PD-L1 ≥10% | Approved 27 Nov 2024 for PD-L1 ≥5% expressers | Missed Jul 2024 PDUFA date because of Sep 2024 adcom |
Rationale-305 | HER2-ve gastric/GEJ adenocarcinoma | 0.80 | 0.74 in PD-L1 ≥5% | Approved 27 Nov 2024 for PD-L1 ≥5% expressers | Dec 2024 PDUFA date |
Source: OncologyPipeline.
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