The PACIFIC trial is concerned with stage 3 non-small cell lung cancer. Typical treatment for those patients with a resectable disease is concomitant chemoradiation. With that treatment that has been the same for the last two decades what you expect to get is median progression free survival of about nine months and 15% of patients being alive at fifteen years. Of course, we need to improve those results and this is one of the recent trials with a novel immunotherapeutic agent had been put forwards.
So the design of the trial had taken patients that did not progress after the chemoradiation treatment with stage 3 disease and then randomised them to receive durvalumab versus placebo in a 2:1 fashion, primary endpoints being progression free survival and overall survival.
We present today the interim progression free survival analysis and show that there was a significant, robust improvement in progression free survival with a hazard ratio of 0.52 at a p level of 0.001. That means an increase in progression free survival in the median time from 5.6 months on the control arm to 16.8 on the durvalumab arm. Consistent with those data there was an improvement in response rates from 16% to 28% and a decrease in the appearance of new metastatic lesions. The safety profile was as expected, as previously described in metastatic patients.
Were there any immune adverse related events?
There was, of course, some increase in the number of immune adverse events. The rate of immune adverse events is in the region of 24% but the number of severe adverse events are pretty low, something like 3.4% which is quite manageable I would say.
Is there any expectation of when the overall survival data might be mature?
For that trial, for the final mature survival you need 491 death events. It’s difficult to say when this is going to happen but at least two to three years to go.
Would you say this brings durvalumab a step closer to approval perhaps?
My particular opinion, of course, is the agency to say it but in my particular opinion it is very likely that an approval would be perceived for that specific indication of stage 3.
Any comparison to other PD-1 antibodies?
The data we have so far comparing one antibody to another are just by comparing across trials. There are no direct comparisons one to each other. So it’s really difficult to say how to compare one to each other. The only thing I can tell you, we are sure about the efficacy of some of the other agents for metastatic disease because the right trial has been performed and in stage 3 disease the only anti-PD-L1 agent that had been actually tested properly and is the only one with robust data.
Would you feel comfortable passing any comment on the results from the MYSTIC trial that came out a little while ago?
To be honest, the only information I got about the MYSTIC trial is the press release and I don’t think I have much data, nothing much to add.