Day 8 on Vectibix (panitumumab)

[Dymueller]

I'm new to this forum, but have been living with a Stage IV Colon Cancer diagnosis since the birth of my youngest child in Oct. 2013.

It's been 8 days since my first infusion of Vectibix. It was given with my 5th treatment of FOLFIRI. I believe I have only one more FOLFIRI treatment with the Vectibix. Then, if it appears to be working well, the oncologist is planning to just keep me on Vectibix.

I'm experiencing the mouth soreness and now intestinal cramping. On day 6, I had excrutiating rectal pain, I imagine due to the many times I had to use the bathroom - no diarrhea, but my body seemed to be cleaning out. I soaked in a bath, tried Tucks pads, used Rx hemmerhoid cream, and finally resorted to 10mg oxycodone.

Can anyone tell me your experience on Vectibix? How long did you experience side effects? What did you find worked in managing them?

[CM35]

I had 3 rounds of FOLFOX+panitumumab. It wasn't pleasant. I found that the side effects kind of waxed and waned regardless of where I was in the cycle. I had the itchy rash, plus I got oral thrush (this may be the cause of your sore mouth-check with your doctor. I was given magic mouthwash and nystatin to treat it)... I was told that after about 6 weeks, the side effects usually moderate a little. I was taken off it for surgery, though, so I can't speak from experience on that one.

Edited to add: I was also on doxycycline and given clindamycin gel for the rash.

[DK37]

Interesting... I am on Erbitux. I hadn't heard people compain of those side effects from Vectibix itself before (has anyone here heard of them who took an EGFR-inhibitor monotherapy)? So maybe unique to the combination of Vectibix with FOLFIRI?

My guess is that these side effects would subside when you switch to Vectibix monotherapy. I've been on Erbitux monotherapy (which in general has identical side effects profile) since March 1 - aside from the rash it has had zero other tox side effects for me. It has kept me stable, a real wonder drug.

If you continue on monotherapy, I can give some hints on rash management - through both good advice & trial & error, I have strong grade 2 rash but it is being managed very well. I find it millions of times better than FOLFOX/FOLFIRI, my personal opinion.

Good luck,
-Dk

[rockyterrain]

Hi everyone, good luck and God bless...

Quick question, everyone on these drugs has CONFIRMED they are mutant RAS-negative, right? Check with your doctor and double-check with the pathologist that the test is capable of seeing all extended-RAS mutations that would otherwise exclude candidates from the drug. It's a newer test and even though EU is compliant since 2013, it's very important that you double-check that you are RAS wild-type for KRAS and NRAS exons 2, 3 and 4. OK?! Not all the labs in the EU are adequately equipped to detect the RAS mutations in both genes along exons 2, 3 and 4... it's way better than here in the US, but still a work in progress in EU.

Best wishes and may you all have speedy recovery.

James

[Dymueller]

Hi everyone, good luck and God bless...

Quick question, everyone on these drugs has CONFIRMED they are mutant RAS-negative, right? Check with your doctor and double-check with the pathologist that the test is capable of seeing all extended-RAS mutations that would otherwise exclude candidates from the drug. It's a newer test and even though EU is compliant since 2013, it's very important that you double-check that you are RAS wild-type for KRAS and NRAS exons 2, 3 and 4. OK?! Not all the labs in the EU are adequately equipped to detect the RAS mutations in both genes along exons 2, 3 and 4... it's way better than here in the US, but still a work in progress in EU.

Best wishes and may you all have speedy recovery.

James

Yes, I've been tested and have Wild-type KRAS.

[Crystald]

Can anyone tell me your experience on Vectibix? How long did you experience side effects? What did you find worked in managing them?

I am on vectibix monotherapy, just got my third infusion.

First infusion I noted a scalded tongue, extreme fatigue, light nose bleeds, alot of gas, and the development of the rash, light at first, then it spread.

PM me anytime to chat.

[rockyterrain]

That's good to hear Dymueller.

Just make sure it's extended-RAS. Majority of labs in the US still only testing "hotspot" KRAS mutations on exon 2, and partial exon 3. The test needs to cover KRAS and NRAS exons 2 3 and 4, collectively called "extended-RAS."

It should be criminal in the US this is not regulated or enforced... drug label for both -mabs changed earlier this year, but as of now no standardization among labs or pathologists...

JD

[DK37]

That's good to hear Dymueller.

Just make sure it's extended-RAS. Majority of labs in the US still only testing "hotspot" KRAS mutations on exon 2, and partial exon 3. The test needs to cover KRAS and NRAS exons 2 3 and 4, collectively called "extended-RAS."

It should be criminal in the US this is not regulated or enforced... drug label for both -mabs changed earlier this year, but as of now no standardization among labs or pathologists...

JD

Great point JD - thank you for spreading the word!
-DK