ESMO 2024: Latest in EGFR mutated NSCLC
Prof Ignacio Gil-Bazo – Catholic University of Valencia, Valencia, Spain
Dr Mariana Brandão – Institut Jules Bordet, Brussels, Belgium
Prof Benjamin Besse – Institut Gustave Roussy, Villejuif, France
Prof Enriqueta Felip – Vall d'Hebron University Hospital, Barcelona, Spain
IGB: Good morning. My name is Ignacio Gil-Bazo, I’m a professor at the Catholic University of Valencia in Valencia, Spain, and it’s my real pleasure to chair this session, this specific expert roundtable on EGFR mutant non-small-cell lung cancer, with a special focus on exon 20 insertions. With me I have a wonderful panel of experts, international experts, to brief a little bit what we’ve seen at ESMO 2024.
MB: Hello. My name is Mariana Brandão, I’m a medical oncologist at Institut Jules Bordet in Brussels in Belgium.
EF: Hello, my name is Enriqueta Felip, I’m a medical oncologist working at Vall d'Hebron University Hospital in Barcelona, Spain.
BB: Hello, my name is Benjamin Besse, I’m a medical oncologist at Gustave Roussy in Paris, France.
IGB: So I think we have a wonderful subset of different clinical trials that have been discussed during ESMO 2024. I think we can start with the LAURA trial in the adjuvant setting after chemoradiation. Mariana, what do you think is the most relevant data presented at that topic?
MB: I think that we were all astonished already this year when we had the first data, the survival data, coming from LAURA, but at ESMO now we had the more detailed information about CNS, so central nervous system, progression in these patients in the trial. I think this is very relevant because Stage 3 actually it’s almost premetastatic, so it’s a very systemic disease, and we know that these patients with EGFR mutations have a very high risk of developing brain metastases. So what we’ve seen, well, it was not so surprising, is that there was a huge decrease in the risk of CNS progression in the patients that received adjuvant osimertinib. So we see that at one year the patients in the placebo arm, already more than one-third had a relapse in their brain, while the patients on osimertinib it was only 9%. So that’s a hazard ratio of 0.17 so it’s a huge decrease. I think that probably none of us was so surprised, because we already have seen this as well in the resectable stage population, but still I think it’s very relevant and maybe this could help us to get osimertinib for these patients in our countries. I don’t know what you think.
EF: I think the results are really interesting. It’s true that we thought at the beginning that perhaps in patients with a stage 3 unresectable there is more the possibility for a cure, but I think these reinforce the treatment until disease progression, these data on CNS metastases.
BB: Maybe one of the limitations is that the baseline workup of these patients is not completely clear, meaning before chemoradiation, PET scan, brain MRI, the population is not clearly defined, and this lifetime treatment in stage 3 is also something we will have to question, because it was three years, first up, maybe three years would be enough, plus chemorad.
IGB: Yes, I think it’s true. We don’t really know what subset of patients are going to really benefit from the whole long-lasting treatment with the potential harm that that can cause, right? And the other thing, regarding the CNS, is that we don’t really know if that protection is going to be long-lasting or if it will eventually end at some point, and we still have the same problem with the patients, right?
MB: Exactly that. I think for that [??] we have that minimal residual disease concept. That would be something that eventually could apply for this population as well. So those with ctDNA clearance, those maybe we could safely stop after one year or two years or three, while those without this clearance, or that have a slower decrease over time, maybe those ones we’ll be more cautious. Maybe another strategy is also monitor them over time and when there is a molecular relapse to restart osimertinib in order to avoid macroscopic disease. That could be another possible way.
IGB: Perfect. And what about the first-line EGFR mutant non-small cell lung cancer for sensitising mutations, what’s been presented at ESMO 2024?
EF: I think the MARIPOSA trial was updated during the World Conference. In this trial patients in first-line EGFR sensitising mutations were randomised to receive osimertinib or amivantamab plus lazertinib or lazertinib. The lazertinib arm was only to analyse the activity of the component. And during the whole conference it was an update of the analysis of the combination versus osimertinib. In this updated information there is a trend towards an improvement in overall survival with amivantamab and lazertinib, when compared to osimertinib. It’s still not statistically significant but there was also numerically a higher number of patients without CNS progression at three years when comparing amivantamab/lazertinib versus osimertinib. So all data suggests that perhaps in the next overall survival analysis we may have differences significant. So the study is positive for PFS and now we have this updated information. So this is another treatment option, knowing the first-line setting, we have the FLAURA2, chemo plus osimertinib, amivantamab plus lazertinib and also osimertinib alone. So now our discussion is what we should consider the first-line treatment approach and define perhaps the patients who most benefit with each treatment strategy.
IGB: Yes, you’re right. And what about MARIPOSA2, what is the update that we have?
BB: So amivantamab can be given either in first-line, MARIPOSA, either in second line plus osimertinib or maybe in stage 3 when they receive osimertinib. The trial compared chemo and chemo plus amivantamab. There is a third arm with lazertinib/amivantamab but without any benefit and more toxicity. So now there is an access to this chemo/amivantamab regimen, there is a benefit in PFS, the OS is still maturing, there is a benefit of around two months in terms of overall survival. It’s borderline significant but it’s not yet. The toxicity profile didn’t change. I think it’s interesting information. We still don’t know what is the best strategy, as you said, and the best sequence between all these treatments.
IGB: And do we have anything relating to mechanisms of resistance that would be worth mentioning?
BB: The mechanism of resistance of amivantamab plus lazertinib were never reported. An analysis of the MARIPOSA trial that you just mentioned, Enriqueta, was presented. We know that with osimertinib the mechanism of resistant cells is usually EGFR mutation and MET amplification. We know the rate, it’s in osimertinib around 13% MET amplification and around 9% EGFR secondary resistance mutation. We know from the FLAURA2 trial that if you give chemotherapy and osimertinib, the mechanism of resistance to osimertinib at the end will be roughly similar. With lazertinib and amivantamab you decrease the amplification of MET, which is expected because it’s a bispecific antibody against MET and EGFR, so you go from 13 to 4%. More surprising, you also decrease the rate of secondary EGFR mutation, you go from 9% to roughly 1%. It means that the drug really works through the two pathways and not only through MET. The other pathways of resistance were roughly similar, a bit less small cell lung cancer transformation with amivantamab/lazertinib but most of the patients that progress on amivantamab/lazertinib have unknown mechanism of resistance. It was done with NGS panel on the circulating tumour DNA, so there is much more to understand. I think this data tells us how the drug works but cannot help us to sequence the different strategies and say this is the best drug you should give first, amivantamab and lazertinib.
IGB: And regarding the SKIPPirr trial with the prevention of the infusion-related reactions, what would you mention about it? Do you think it is really relevant?
BB: So, we know that with IV amivantamab the rate of reaction, it’s really the first drop, the other infusions usually are really safe but the first drop you can have around 67% reaction. The SKIPPirr trial tested prevention with dexamethasone, 4mg twice daily, 3 days, and you start two days before amivantamab and you decrease from 67% to 24% with only one grade 3 in the patients treated, so it seems to be a good strategy. We all know that the sub-cue version of amivantamab also decreases this reaction. It’s a two-hour infusion, so I think we all wait for the sub-cue that will be much easier for the patients and the staff of our hospital.
IGB: OK, but I think we can say that we could be ready to treat or pretreat our patients with 8mg of dexamethasone until we have…
BB: Yes, I agree. I’m saying we can implement right now.
IGB: Perfect. So good. And we also have two relevant studies in the exon 20 insertion landscape that are probably worth mentioning. I think the PAPILLON trial is a very well-known trial for the first-line, associating chemotherapy and amivantamab in these patients, and for the first time we’ve seen that that combination is really the standard of care for a hard to treat population in the setting. What has been updated is how the current mutations and specifically TP53 alterations that are very well-known to be mechanisms of resistance to third-generation EGFR TKIs, in this case with that combination we are still protecting the patients and we are delivering the same amount of benefit for the concurrent TP53 positive population as compared to the wild type. The other alterations that currently happen also in that resistance mechanism do not appear to be the case when we use amivantamab in combination with chemotherapy. So I think that is another interesting way to see how the drug is working, which is completely different from what we’ve seen with the traditional EGFR TKIs. And we also have the RESILIENT trial.
MB: Indeed. It’s about the new TKI that is really targeting EGFR exon 20. Which is interesting because all of a sudden we have now more options for these very hard to treat mutations. So zipalertinib is a TKI specific for EGFR exon 20 and we already had some data for patients progressing on platinum-based chemotherapy with an overall response rate about 40%, but like we were discussing, now the new standard of care is chemo plus amivantamab, so it will be interesting to see if this is still working on these pretreated patients. So that’s the data that we have now in these patients that have received amivantamab. It’s interesting to see that overall the response rate is still very high, it’s also 40%. In patients that only receive pure amivantamab, so no other TKIs, no other things, it’s up to 50%. In terms of toxicity, it’s the common rash, dry skin, so nothing really different from what we already know from previous TKIs. So I think it’s nice to see that now we could have something to sequence for patients with EGFR exon 20, and maybe this could even make us think in the future that we could actually associate amivantamab with these new TKIs, like we have amivantamab plus lazertinib, and provide a chemo-free option in first line for these patients. Then eventually they will have chemotherapy or other targeted therapies afterwards. So I think it’s very good news because the previous TKIs in this setting were a bit disappointing, and this could be an alternative, especially for patients that already received amivantamab.
IGB: I think we also have some data for the EGFR mutant population in general, for the second line we also have this eternal question regarding the immunotherapy activity and maybe this may change since we use different drugs, targeting not only PD-1/PD-L1 but also something else. Benjamin, what do you think about this?
BBL The phase IIIs that have compared chemo and chemo plus single agent PD-1 blocker are all negative and we know that it doesn’t bring any benefit to these patients. The only one that is a bit positive is the IMpower150 where it’s atezolizumab plus bevacizumab and we know that the antiandrogenic works in the space of EGFR. We don’t know really the biology but there are drugs that are approved, like ramucirumab or bevacizumab, combined with a TKI. There is a new generation of bispecific antibodies like evinacumab that target both VGFR and PD-1. The evinacumab is I think currently in phase 3 with chemotherapy plus a TKI and there is a newcomer, PM8001, that is exactly the same design, the bispecific antibody, and it’s the phase II data that we have seen, chemo plus this agent, in patients with activating EGFR mutation. The response rate is around 50%, up to 90% in the patients with high PD-L1. Interesting to see that there is a trend with PD-L1 because it means that it might work not only through VGFR, VGF inhibition, but also through PD-1. So the story of immunotherapy is not completely over in the space.
IGB: I agree. So we don’t really have much time, but maybe if you just want to say a take-home message, very quick, for what you’ve seen more relevant in this ESMO. Mariana?
MB: For the EGFR I think we are starting to really dissect the possibilities that we have in first line in understanding the mechanisms of resistance and really trying to understand how we can sequence these treatments better. Still, of course, these are still clues, we don’t have clear directions. But for me, my take-home message is indeed on the stage III I was a bit still waiting for the OS data but now also the CNS, despite the problems with methodology, I also accept that, I think it reinforces the value of treating these patients in the earlier setting with EGFR inhibitors.
EF: I think for me, for patients with sensitising EGFR mutations we have more treatment options and it’s important in first line and also in second line. I think we have learnt mechanisms of acquired resistance that could help us in the future to define the strategy. And in the area of EGFR exon 20 insertions, I think also the sequence. For me, what you have mentioned, we have treatments that may be active after amivantamab and also I think we’ll have to find that probably the baseline p53 mutations in all the tumours activating and also EGFR exon 20 insertions is more prognostic than predictive.
BB: We have a lot of options for activating EGFR mutations. I think there is no perfect first line and no strategy should be better. Even single-agent osimertinib could also be a strategy and then escalate at the time of resistance. We all have very long responders to osimertinib and we say why should I escalate from the beginning in these patients that in fact will have three, four, five years of osimertinib? I’m a real believer on the ctDNA monitoring and I think that that has been shown that after four weeks of OZ or amivantamab/lazrtinib around 25% of the patients don’t have clearance of ctDNA. I think this is the prognostic population in which we have to escalate. So a strategy based on that, I think really something we should explore.
IGB: And from the exon 20 insertion point of view, I think we have still a very good first line, which is already the standard of care associating amivantamab plus chemotherapy. Of course we still need to know a little bit more about the details of the biology, and we have learned some interesting data from the concurrent mutations and how this strategy still works very well for that population. We have also some new drugs coming to the stage to try to test its efficacy, so I think there is hope also for this sub-population of hard to treat tumours. So, with that, I just want to thank all the speakers, the experts, for this wonderful discussion and thanks everyone for watching.
