We presented the NorthStar study, it’s a phase II randomised trial that took place at multiple centres across the US. It’s a study in metastatic lung cancer for patients with an EGFR exon 19 deletion or L858R mutation. The idea is that many patients respond really well to osimertinib but many go on to progress pretty quickly. So in this study patients received osimertinib for 6-12 weeks and as long as they did not have any progressive disease they were randomised to continuing osimertinib, which is the standard of care, versus receiving local consolidative therapy to their primary tumours or any other residual sites of disease, either with radiation or surgery, to see if that can prolong the time that patients are on osimertinib.

What was the study design?

It was a phase II randomised study and the primary endpoint was progression free survival. The study actually met its primary endpoint, this was presented at ESMO last year. In the study that we presented here we focussed in on really questions of how effective is radiation and we reported that about 70% of the patients received radiation as part of their local consolidative treatment. It was really effective in terms of controlling their tumours – over 90% of patients had good local control from the radiation.

We also wanted to look into patients who really drove the benefits, or who are the subset of patients that really benefit from this treatment. We found that patients who were able to not have a pleural effusion or not have mediastinal nodes after induction therapy are really the ones that benefit the most from local consolidation.

What could be the clinical significance of these results?

This looks like we were able to prolong the amount of time that patients were able to stay on osimertinib. It’s a drug that is very well tolerated and we showed that radiation is also really well tolerated. So by adding radiation to Tagrisso patients are able to stay on treatment for a longer period of time before having to move on to second-line therapies that potentially could be more toxic.

What’s next for this study?

Next we’re looking to do another phase II randomised study that looks at osimertinib as well as chemotherapy with local consolidation. So there’s a study, FLAURA-2, that was presented last year which showed that patients who received chemotherapy with osimertinib tend to do better than osimertinib alone. So we’re going to add local consolidation on top of that systemic therapy backbone to see what the outcomes look like.