Also, what do you think of Valcyte? My brother has been taking it for nearly 12 mths. Nothing came up when I searched on this forum.
This is worth starting a new thread about, since we haven't discussed in on the blog yet.
Clinical studies on this drug for glioblastoma have generated a great deal of controversy. For a primer on this controversy see the Valcyte section on the Repurposed Drugs page at Astrocytoma Options.
The original, small, prospective, "hypothesis generating" clinical trial showed no improvement in overall survival or progression-free survival for patients randomized to receive Valcyte. The study's primary endpoint was tumor volume at 3 and 6 months post-surgery, so patients in the placebo arm were allowed to cross over to Valcyte after six months, which could have masked any overall survival benefit of Valcyte compared to placebo, but there was also no improvement of PFS.
Then a retrospective study, including patients in this trial plus another group treated with Valcyte on compassionate use, was published in the New England Journal of Medicine, and this is when the real controversy began. This study is affected by a form of bias called "immortal time bias", which commentators were quick to point out. Still, other commentators such as Charles Cobbs claims there was an unexpected number of longer-term survivors.
Multiple preclinical studies have demonstrated a role of CMV in glioblastoma progession, providing at least a rationale for the use of Valcyte. I simply don't know what to think about Valcyte. It's remarkable how a prospective study could show no improvement in median PFS, while further retrospective study could claim large benefits. That said, I fully understand why patients would want to try this drug, on the chance that it could truly be helpful.
We went to see Dr. Cobbs this week to see if Don was a candidate for surgery since someone mentioned previously he wasn't. Obviously he is a very big fan of Valcyte. He did agree there was an issue with the studies. He met with the drug company to convince them to consider further study but so far, no luck. He recommended disulfiram as well. He sent in the RX and the pharmacy called and said our share was $1800 for one month supply of Valcyte.
ReplyDeleteHi, I have heard of several patients getting it from Genetech free of charge. I would pursue this. Also, if this doesn't work you can obtain it from a legitimate and safe Canadian pharmacy for aroud $600 per month. We were fortunate in the our insurance Anthem BCBS paid for it as an off label drug.
DeleteI may go back and ask Cobbs if his tumor can be checked for CMV. Has anyone done that?
ReplyDeleteI may be wrong, but my understanding is that they can't yet do this testing at Swedish. It's also my understanding that when they test GBM samples using the proper techniques, they almost always find evidence of CMV proteins and nucleic acids.
DeleteThanks Stephen. Yes, I too read the % of CMV is traditionally high. Curious, where do they do the testing?
DeleteMaybe at University of Alabama, where Cobbs et al. originally developed their methods. Cobbs wrote in 2014
Delete"Our sensitive CMV protocols have been published, and we are
in the process of developing an automated IHC and in situ hybrid-
ization (ISH) reference lab to perform these studies."
So maybe they do have this capability at Swedish now. Would be worth finding out.
My brother had a blood test to check for CMV. Not sure if this is the same as testing the tumour?
DeleteThe expense of Valcyte is definitely a major drawback. Generic valganciclovir is cheaper than brand name Valcyte, but even the generic is $700 - $1500 for 30 tablets (450 mg each) according to goodrx.com
ReplyDeleteDear Lisa,
ReplyDeleteHas your brother had any recurrence of tumor since he started Valcyte? A neuropathologist in a florida cancer center said he started testing GBM tumors for CMV because of patient request. I don't know how many he tested, but all that he tested showed negative. This doesn't sound right considering 90% of tumors supposedly show positive for CMV. I am new to this site and am also interested in Valcyte and why there are very few physicians on board with it. Kim
I was just at a talk at the Seattle Science Foundation where the CMV expert (Cecelia: http://www.ceric.se/Research/Cecilia/Cecilia.html) said 100% of their 451 tumors tested positive for CMV. Here is the link to the talk: https://www.youtube.com/watch?v=DSujOx_qT0M
DeleteThank you Annie. It was a great discussion to view online.
DeleteThank you for sharing Annie, this is really interesting to listen to.
DeleteHi Kim, sorry I've just seen your comment.
ReplyDeleteDavid hasnt had a recurrence since his 2nd surgery in January 2015. This was found to be mostly necrosis. He is still very well and the last 2 or 3 MRI's have shown a decrease in size of whatever is left.