Tarlatamab

7.1 The PBAC did not recommend tarlatamab for the treatment of extensive-stage small cell lung cancer (ES-SCLC) with disease progression on or after first line treatment with platinum-based chemotherapy. The PBAC noted there is a high clinical need as ES- SCLC is a rapidly progressive disease and there are limited effective treatments in the second- and later-line settings.PSD · Mar 2026

The PBAC agreed with the ESC that revision to the economic model was required to address key uncertainties. The PBAC noted that incorporating the ESC’s recommended revisions, together with the price proposed in the pre-PBAC Response, resulted in an unacceptably high incremental cost-effectiveness ratio (ICER).PSD · Mar 2026

6.51 The submission presented a modelled economic evaluation comparing tarlatamab with topotecan (as a proxy for SOC) for the second-line treatment of ES-SCLC in patients with disease progression on or after platinum-based chemotherapy. Third- line tarlatamab treatment was not modelled in the economic evaluation. The economic evaluation was based on the results of the DeLLphi-304 trial, with additional modelled data.PSD · Mar 2026

6.52 Table 8 summarises the key components of the economic evaluation. 22PSD · Mar 2026

6.45 The submission described tarlatamab as superior in terms of effectiveness and safety compared to SOC for the treatment of second-line and subsequent treatment of ES- SCLC in patients who had progressed on or after platinum-based chemotherapy. The ESC agreed with the evaluation that this claim may be reasonable in terms of efficacy, but not safety. 6.46 The following issues should be considered:PSD · Mar 2026

• The generalisability of the DeLLphi-304 trial results to the proposed PBS population is unclear, given patients in the trial were required to have an ECOG performance status of 0 or 1 and a minimum life expectancy of 12 weeks, the trial included patients with limited stage disease, and 40% of patients received tarlatamab beyond disease progression (which is inconsistent with the proposed restriction).PSD · Mar 2026

6.84 The PSCR noted that the proposed treatment duration for tarlatamab used in the financial analysis reflects treatment until progression however acknowledged there was a risk of use beyond progression. The sponsor noted it was willing to adopt a risk sharing arrangement to manage the risk of treatment beyond that projected in the financial estimates. For more detail on PBAC’s view, see section 7 PBAC outcome.PSD · Mar 2026