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could it also be dose related? any idea on the dosages used in animals versus what is used in humans?
cheers!!
I've read it somewhere.. can't find the article now. The dose which was used was VERY VERY high.. and over a long period of time (i think 2 years?) Calculated on a human, you never ever would take such huge doses (i think they talked about 6000mg daily, im not sure).. 2 years on 13 valcyte tablets a day..... normal therapeutical dose is 2 tablets a day.
Furthermore someone here said, that the animals developed cancer in areas, which doesnt exist in humans.
People with transplanted organs HAVE TO take Valcyte 6-12 months.. i think if the risk of cancer would be that high, no one would take it.. no doc would give it to you
Thanks copi2k - that's interesting.
I need some references - my doctor doesn't want me to go on Valcyte, partly because of the cancer risk and I need to go to my next appointment armed with journal articles or whatever hard info there is. I'd be really grateful if someone could point me at something.
In the meantime, that's interesting about the animals (I'm wondering what bits they've got that we don't!) and the transplant patients. You'd think there'd be some data on transplant patients.
it sounds more like an excuse for your doc not to prescribe it, maybe just doesnt understand valcyte well as not many docs have probably ever prescribed it. Sounds like an arse covering exercise from your doc but could be wrong. I would maybe consider finding another doc to prescribe it and who will work with your current doc if he is good for other treatments etc
good luck with it.
understand how hard it is there. Any chance of crossing the pond to see a doc?Hi heaps - I live in the UK and am within the NHS system. It's my GP who doesn't want to risk it but he's referred me on to an infectious diseases consultant who might, if I can go armed with the facts. It's the nature of the system here - if you request something that isn't usual for the NHS (and the treatment of high HHV-6 titres with Valcyte for people who don't have HIV or have had an organ transplant or similar) you've got no chance of getting it unless you go in with all the facts. There's a limit to how many specialist referrals I can get before my GP will stop sending me. My GP does his best within the limits of the system - getting another GP will just get me another one dealing with the same system.
A long way of saying that I need the scientific literature about the cancer risk. I'd also like the info for myself, let alone my doctor!
No chance, I'm afraid - but regardless of what my doc wants, I also want this info so I can make my own informed judgement.understand how hard it is there. Any chance of crossing the pond to see a doc?
I don't know that this is helpful:
http://www.medicalnewstoday.com/releases/8455.php
Ganciclovir (Valcyte(reg)/Cymevene(reg)) reduces risk of cancer in kidney transplant patients
Hope123 said: If I remember right, the cancer risk related to Valcyte was from studies in mice who took higher doses and the cancer developed in tissues that did not have an analagous component in humans.I remember Dr. Montoya saying something to that effect and similar rumors on message boards. The actual drug information sheet says both of those statements are false. Yet another thing I have realized only later harmful about his treatment and interaction with patients. Also receiving the same dosage as patients twice my weight (the average American)."Toxicity in mice, dogs and rats was primarily characterised by testicular atrophy. Male infertility occurred at doses of 2 mg/kg/day and above which was consistent with the infertility and testicular atrophy seen in toxicity studies with doses between 2 and 10 mg/kg/day. In females, a more complex range of effects were induced which were characterised by embryo-foetal abnormalities and embryo-foetal losses in mice and rabbits and in multi-dose studies, by toxic and eventually carcinogenic changes to the reproductive system in mice.Ganciclovir was carcinogenic in the mouse after oral doses of 20 mg/kg/day for 18 months and 1000 mg/kg/day for 15 months. All ganciclovir-induced tumours were of haematopoietic epithelial or vascular origin. Epithelial tumours involved a wide variety of tissues, including the female reproductive organs, pancreas, gastrointestinal tract and skin, as well as rodent specific glands (perputial, clitoral and Harderian). Vascular tumours were observed in females, mainly in the reproductive organs, but also in the mesenteric lymph nodes and liver. No carcinogenic effects occurred at 1 mg/kg/day. Based on data on plasma drug concentrations, exposure of humans to ganciclovir would be similar to or greater than the exposure of mice in the above study at 1000 mg/kg/day. This potential is likely to be markedly greater in children, as cell division occurs more rapidly in children."
Low nk function can increase the risk of cancer. Some after treatment with antivirals have had improvement in nk function, some havent. I dont know if theres an answer, in general theres little know about hhv6 etc compared to other causes. As for nk function, its role is to kill viruses and cancer cells. I think all i have done is muddy the water for you.
Are there any stats on this? A swift google shows me that Valcyte has caused tumours in animals but I can't see any data on humans.
Any studies?