LDK378 (Ceritinib) Study Published in NEJM

A couple of people have kindly pointed out that I have been reading these medical studies for too long and I am starting to sound like them. For short summary see bottom of post. So here is an attempt to put the results in more regular English.

The overall response rate is essentially the percentage of patients benefiting from the drug. So if 100 patients took the drug then 58% would see their tumors shrink by 30% or more (that is an industry standard to make sure everyone is using the same objective criteria).

Now in my opinion this industry standard can understate the benefit of the drug significantly, and in my opinion it has in this case. The stable disease category covers patients who’s tumors are truly unchanged (but if that lasts for 4-8 months I would call that good news). It also covers patients whose tumors shrank 1% to 29%.

In this study, the stable disease rate was 22%. So in my mind that means close to 80% of patients benefited from the drug.

Here is another way to visualize the information(see link below for a different but very similar drug I was on previously). These are called waterfall graphs. Basically the more the tumors have shrunk the further to the right they are on the graph. The dashed 30% line indicates the official cut off of who benefited. As you can see many patients benefited (just to a lessor degree). The only people who did not obviously benefit are on the far left, and they may have benefited by having their cancer grow at a slower rate than it would have otherwise.


Another subtle but significant fact is that the overall response rate is 56% for patients who were previously treated with Crizotinib but developed resistance to the Crizotinib (basically it stopped working).

This is good news because patients can usually start on Crizotinib and then switch to Ceritinib and generally get the benefit of both drugs (which is what has happened for me). This has sometimes not been the case for other targeted therapies.

There are other nuances but those are the main points.

*overall response rate of 58% (Crizotinib naive 62%, Crizotinib resistant 56%).
*median progression-free survival of seven months (8.2 months for responding patients?)
*114 patients in study
*responses were seen in untreated lesions in the central nervous system in patients who previously received crizotinib
*active in patients with or without new mutations in the ALK gene

This entry was posted in Brain metastases, ceritinib - Zykadia from Novartis, Lung cancer, Potential Treatments, Regulatory applications & approvals, Research, Resistance to treatment, Side Effects. Bookmark the permalink.

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