Wednesday, March 28, 2018

Encorafenib plus binimetinib better than vemurafenib or encorafenib alone in melanoma! Well, duh!!! We already knew that a BRAF/MEK combo is better than a single agent!!!!


I report this again only because "they" are!  Institutions, Big Pharma, and researchers like to have their name in lights.  So, I will shine my spotlight once again!  I reported on and evaluated the results of the COLUMBUS study here, back in May of 2017:  Encorafenib/binimetinib, a BRAF/MEK combo = 14.9 month PFS 

Now that title statement, is absolutely true and good!!!  In that report, I went to the trouble to look up these stats:

From The coBRIM trial - August 2016 we learned - that when cobinmetinib and vemurafinib were combined, the median overall survival (OS) was 22.3 months and the median progression free survival (PFS) was 12.3 months.

From this discussion of BRAF/MEK and immunotherapy (Nov 2016)  we learned = that generally treatment that was a combination of a BRAF inhibitor and a MEK inhibitor could illicit a response rate of 48-59%, even as much as 70% with some combo's and PFS of 11-12 months.


So, yes...the encorafenib with vemurafenib combo has a better PFS than the combo's noted above ~ at least in this study of the 192 BRAF positive unresectable/metastatic Stage IIIB/C or Stage IV peeps  who were given it below.....

Encorafenib plus binimetinib versus vemurafenib or encorafenib in patients with BRAF-mutant melanoma (COLUMBUS): a multicentre, open-label, randomised phase 3 trial. Dummer, Ascierto, Gogas,...Flaherty, et al.  Lancet Oncol. 2018 Mar 21. 
Combined BRAF-MEK inhibitor therapy is the standard of care for BRAFV600-mutant advanced melanoma. We investigated encorafenib, a BRAF inhibitor with unique target-binding properties, alone or in combination with the MEK inhibitor binimetinib, versus vemurafenib in patients with advanced BRAFV600-mutant melanoma.

COLUMBUS was conducted as a two-part, randomised, open-label phase 3 study at 162 hospitals in 28 countries. Eligible patients were aged 18 years or older and had histologically confirmed locally advanced (stage IIIB, IIIC, or IV), unresectable or metastatic cutaneous melanoma, or unknown primary melanoma; a BRAFV600E or BRAFV600K mutation; an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1; and were treatment naive or had progressed on or after previous first-line immunotherapy. In part 1 of the study, patients were randomly assigned (1:1:1) via interactive response technology to receive either oral encorafenib 450 mg once daily plus oral binimetinib 45 mg twice daily (encorafenib plus binimetinib group), oral encorafenib 300 mg once daily (encorafenib group), or oral vemurafenib 960 mg twice daily (vemurafenib group). The primary endpoint was progression-free survival by blinded independent central review for encorafenib plus binimetinib versus vemurafenib. Efficacy analyses were by intention-to-treat. Safety was analysed in patients who received at least one dose of study drug and one postbaseline safety assessment. The results of part 2 will be published separately. This study is registered with ClinicalTrials.gov, number NCT01909453, and EudraCT, number 2013-001176-38.

Between Dec 30, 2013, and April 10, 2015, 577 of 1345 screened patients were randomly assigned to either the encorafenib plus binimetinib group (n=192), the encorafenib group (n=194), or the vemurafenib group (n=191). With a median follow-up of 16·6 months, median progression-free survival was 14·9 months in the encorafenib plus binimetinib group and 7·3 months (5·6-8·2) in the vemurafenib group. The most common grade 3-4 adverse events seen in more than 5% of patients in the encorafenib plus binimetinib group were increased γ-glutamyltransferase (18 [9%] of 192 patients), increased creatine phosphokinase (13 [7%]), and hypertension (11 [6%]); in the encorafenib group they were palmoplantar erythrodysaesthesia syndrome (26 [14%] of 192 patients), myalgia (19 [10%]), and arthralgia (18 [9%]); and in the vemurafenib group it was arthralgia (11 [6%] of 186 patients). There were no treatment-related deaths except for one death in the combination group, which was considered possibly related to treatment by the investigator.

Encorafenib plus binimetinib and encorafenib monotherapy showed favourable efficacy compared with vemurafenib. Overall, encorafenib plus binimetinib appears to have an improved tolerability profile compared with encorafenib or vemurafenib. Encorafenib plus binimetinib could represent a new treatment option for patients with BRAF-mutant melanoma.  

But...  Here are some comments I made (in red) in the prior post which provides more info about the trial and trial results than this re-run abstract just posted in the Lancet:

Those with untreated CNS lesions, leptomeningeal metastases, uveal melanoma, and mucosal melanoma were excluded from the trial. [Why the hell not???? You could put them in their own separate group, so as not to sully your results Array CEO person!!! And still give them access to the drug!]

In Part 1 of the study, the median PFS was 14.9 months with the combination of encorafenib and binimetinib compared with 7.3 months for vemurafenib alone. The improvement in PFS represented a 46% reduction in the risk of progression or death. [That's good, but of course we have learned never to give vemurafenib, a BRAF inhibitor without a MEK inhibitor!!! So that's a bit of a false comparison!]

The objective response rate (ORR) with the combination was 63%versus 40% with vemurafenib. [Again...not comparing apples to apples...we KNOW that response rates are better with a BRAF/MEK combo!!!] With single-agent encorafenib, the ORR was 51%. [This fact can at least be compared to single agent vemurafenib response rate of 40%.]

Grade 3/4 AEs were experienced by 58% of patients treated with the combination versus 66% and 63% with encorafenib and vemurafenib, respectively. [As previously demonstrated, side effects were DECREASED with a BRAF/MEK combo.]

Okay.  My synopsis is this:  Generally, prior studies of BRAF/MEK combos demonstrate about a 12 month PFS.  This combo showed a PFS of 14.9 months.  Objective response rate was 63% with the comb0.  There was an ORR of 51% to encorafenib alone.  Objective response rates to BRAF/MEK combo's in other studies have ranged from 48-70%, depending.  OS data for encorafenib/binimetinib has not yet been reported.  OS in most other BRAF/MEK combo's is around 2 years.  The combo discussed here demonstrated fewer side effects than when the BRAFi component was used alone....which is consistent with other reports using a BRAF/MEK combo vs BRAFi alone.

PFS of 14.9 months is better than 12.  Wish they had allowed testing in a greater swath of patients. (But I say that about most all trials!!!)  We'll have to see what the OS data shows and if these current figures hold in future cohorts.  Hang tough ratties.  You will save us all. - c

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So....yep.  Pretty good sum up, I'd say.  STILL have no OS data.  Which is possibly good...in that they are having to watch it a long time, because these ratties are still trucking!  Or, possibly not good...and Array and the researchers just haven't wanted to put it out there yet!  (Oh, yeah...I'm definitely in the pocket of Big Pharma, right?  Just a little inside MPIP humor there!!!)  Hopefully, those numbers will be good and the Encorafenib/Binimetinib BRAF/MEK combo will be an improvement over current BRAF/MEK combo's for BRAF positive melanoma peeps.  However, the problem with this trial is just as it so often is with others: 
1.  We don't compare apples to apples. 
2.  We leave out folks (brain mets, LMD, ocular, and mucosal melanoma patients) in serious need....cause WHY????  (Yeah, I actually know.  Those folks do not respond as well to most current therapies and make your products look bad don't they Array, BMS, Merck...and all the rest of you???) 
3.  We don't base trial questions on what we already KNOW!!!
4.  Results are slow in coming.
5.  We saw the same logs over and over.

Still...ratties rock and will save the day! - c

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