A View on Drug Development for Cancer Prevention

Despite some notable successes, there are still relatively few agents approved for cancer prevention. Here we review progress thus far in the development of medicines for cancer prevention, and we outline some key concepts that could further enable or accelerate drug development for cancer prevention in the future. These are summarized under six key themes: (i) unmet clinical need, (ii) patient identification, (iii) risk stratification, (iv) pharmacological intervention, (v) clinical trials, and (vi) health care policy. These concepts, if successfully realized, may help to increase the number of medicines available for cancer prevention.

SIGNIFICANCE

The huge potential public health benefits of preventing cancer, combined with recent advances in the availability of novel early detection technologies and new treatment modalities, has caused us to revisit the opportunities and challenges associated with developing medicines to prevent cancer. Here we review progress in the field of developing medicines to prevent cancer to date, and we present a series of ideas that might help in the development of more medicines to prevent cancer in the future.

Cost Effectiveness of Durvalumab in Unresectable Stage III NSCLC: 4-Year Survival Update and Model Validation from a UK Healthcare Perspective

BACKGROUND

In the phase III PACIFIC study, durvalumab improved survival versus placebo in patients with unresectable stage III non-small-cell lung cancer (NSCLC) whose disease had not progressed after platinum-based concurrent chemoradiotherapy. The appraisal by the UK's National Institute for Health and Care Excellence (NICE) included a cost-effectiveness analysis based on an early data readout from PACIFIC [March 2018 data cut-off (DCO); median follow-up duration 25.2 months; range 0.2-43.1]. Uncertainties regarding long-term survival outcomes with durvalumab led to some challenges in estimating the cost effectiveness of this therapy.

OBJECTIVE

Here, we validate the survival extrapolations used in the original company base-case analysis by benchmarking them against updated survival data from the 4-year follow-up analysis of PACIFIC (i.e. approximately 4 years after the last patient was randomised; March 2020 DCO; median follow-up duration 34.2 months; range 0.2-64.9). Moreover, we update the original analysis with these more mature survival data to examine the consistency of key economic outputs with the original analysis.

METHODS

The original analysis used a semi-Markov (state-transition) approach and was based on patients whose tumours expressed programmed cell death-ligand 1 on ≥ 1% of cells (to reflect the European licence for durvalumab). We benchmarked the survival extrapolations used in the original company base-case analysis against survival data from the 4-year follow-up of PACIFIC and updated the cost-effectiveness analysis with these more mature survival data. Early deaths avoided by the adoption of durvalumab into the UK Cancer Drugs Fund (CDF) in March 2019 were estimated using the 4-year follow-up survival data and an assumed uptake of 125 patients/year (lower estimate) and 367 patients/year (higher estimate).

RESULTS

The original company base-case analysis had a good visual fit with the observed overall survival (OS) distribution for the durvalumab arm and accurately predicted the 48-month OS rate (predicted 55%; observed 55%); by comparison, the fit was less precise for the placebo arm, for which the analysis underestimated the 48-month OS rate (predicted 32%; observed 38%). In the updated company base-case analysis, durvalumab yielded 2.51 incremental quality-adjusted life-years (QALYs) (- 0.43 vs. the original company base-case analysis), corresponding to an incremental cost-effectiveness ratio of £22,665/QALY (+£3298 vs. the original analysis), which falls within the upper bound of NICE's willingness-to-pay threshold (£30,000/QALY gained). We estimate that between 31 and 91 early patient deaths may have been avoided by the adoption of durvalumab into the CDF.

CONCLUSIONS

These findings reinforce the patient benefit observed with durvalumab in unresectable stage III NSCLC, support the routine use and cost effectiveness of this therapy, and demonstrate how appropriate modelling can inform the early adoption of therapies by payers to achieve patient benefit.