Aa
PCR sensitivity range
having a hard time finding a lab that does a Quant PCR below 43 IU.
Labcorp temporarily shut down NGI QuataSure/UltraQual.
Anybody know a lab that does a more sensitive PCR , possibly in NY merto area ?
Labcorp temporarily shut down NGI QuataSure/UltraQual.
Anybody know a lab that does a more sensitive PCR , possibly in NY merto area ?
TECHNICALLY, you are detectable, because, well, they were able to detect the virus. It's that simple.
But, for many years, and many studies (even very recent ones), they used <50 as the value for undetectable. I wouldn't sweat it. <25 is a very sweet place to be indeed. You should be totally undetectable shortly.
Remember the difference between 50 and 25 in terms of viral load is....
almost zilch. Seriously. Especially this early in your treatment.
RBW
But, for many years, and many studies (even very recent ones), they used <50 as the value for undetectable. I wouldn't sweat it. <25 is a very sweet place to be indeed. You should be totally undetectable shortly.
Remember the difference between 50 and 25 in terms of viral load is....
almost zilch. Seriously. Especially this early in your treatment.
RBW
Now I'm really confused, I started Gilead trial/TX on 2/22/11 by 3/09/11 I was told my vl was <25 but detectable by my PA, on a phone visit with my recruiter/monitor on 3/22/11 I was told my vl was <25 so I asked if that was detectable and she told me no but I had to finish the 48 weeks of tx so I would have a better change of SVR post TX. Bottom line, am I HCV detectable at <25 or not? C O N F U S E D.
Thanks,
Sherri
Thanks,
Sherri
Adding tela towards EOT is certainly an option I've discussed with my doctor should things not work out as I hope. I'm keeping all options open, including stopping my current tx if conditions warrant that in the future.
For now, I remain optimistic. Week 20 labs are due in a few days. As always, we'll use that info in plotting the course.
RBW
For now, I remain optimistic. Week 20 labs are due in a few days. As always, we'll use that info in plotting the course.
RBW
Its my understanding that the few hangers on are what return, they revert back to wild type, your original virus, once the drugs leave the system. This is because even with soc and ntz they seem able to survive and retain enough information of their original coding to return to a healthy (not for you) poulation once the Soc is gone.
Now, for my money, were I treating right now as you are, I'd try to puch it with a PI before ending tx...of course you are in a trial, so they won't want you to....not sure if they could stop you though, assuming a doctor would add a PI to your regime before long.
My doctor said the PI's may come this spring, or summer by the latest probably.
Maybe, the trial will let you have the PI once its disclosed that you were in the placebo arm, some trials do. Do you know if yours will??
Willing plans on punching the PI in when it comes out...it remains to be seen how well this might work, but it might...after all, the trials that let people have the PI in the end did see good SVR rates...just some thoughts.
As to your statement, I think mutation is always involved, mutation is the reason half don't cure. Call it adaptaion or mutation, either way, the virus survives by changing.
The PI's can cause some permenant adaptations, which is why the worry has been so pronounced. With the SOC, the virons revert back to wild type, with the PI's there's more chance they won't, and therefore more chance of creating a very drug resistant new strain, which is why it will be EVEN MORE IMPORTANT to have accurate PCR's while treating for the PI....that way, if the virus is resisting even that drug regime one would cut the losses and wait for the next wonder drug. Otherwise, a full course with a PI might preclude a person from treating for years because they would have such a resistant strain.
ANyway, that's the way I understand the latest studies, in laymens terms, but feel free to show me anything that disproves these theories.
My best to you!!
mb
Now, for my money, were I treating right now as you are, I'd try to puch it with a PI before ending tx...of course you are in a trial, so they won't want you to....not sure if they could stop you though, assuming a doctor would add a PI to your regime before long.
My doctor said the PI's may come this spring, or summer by the latest probably.
Maybe, the trial will let you have the PI once its disclosed that you were in the placebo arm, some trials do. Do you know if yours will??
Willing plans on punching the PI in when it comes out...it remains to be seen how well this might work, but it might...after all, the trials that let people have the PI in the end did see good SVR rates...just some thoughts.
As to your statement, I think mutation is always involved, mutation is the reason half don't cure. Call it adaptaion or mutation, either way, the virus survives by changing.
The PI's can cause some permenant adaptations, which is why the worry has been so pronounced. With the SOC, the virons revert back to wild type, with the PI's there's more chance they won't, and therefore more chance of creating a very drug resistant new strain, which is why it will be EVEN MORE IMPORTANT to have accurate PCR's while treating for the PI....that way, if the virus is resisting even that drug regime one would cut the losses and wait for the next wonder drug. Otherwise, a full course with a PI might preclude a person from treating for years because they would have such a resistant strain.
ANyway, that's the way I understand the latest studies, in laymens terms, but feel free to show me anything that disproves these theories.
My best to you!!
mb
I'm aware that the earlier the virus in undetectable, the better chance for SVR, and obviously, the lower the limit of detection, the better. I don't dispute the science, nor would I encourage anyone else to.
For me, personally, repeated low level testing would only be a source of stress. And that is counterproductive to me in my quest to rid myself of this beast.
I've had three hepatologists tell me there is no way they would urge anyone with viral load results like mine at week 12 to stop therapy. I'm figuring I have at least 50/50 odds, and that's good enough for me. So I'm rocking on.
Finally, it's important to remember that the difference between a viral load of 24 and a viral load of 9.7 is for all practical purposes... nothing.
I don't think mutations apply unless a DAA is involved. I could be mistaken. I'm doing IFN/RIBA, since I was unfortunate enough to draw the placebo in this study.
I'll know in about 72 more weeks at my 6 month post-tx PCR whether it paid off or not :-)
RBW
For me, personally, repeated low level testing would only be a source of stress. And that is counterproductive to me in my quest to rid myself of this beast.
I've had three hepatologists tell me there is no way they would urge anyone with viral load results like mine at week 12 to stop therapy. I'm figuring I have at least 50/50 odds, and that's good enough for me. So I'm rocking on.
Finally, it's important to remember that the difference between a viral load of 24 and a viral load of 9.7 is for all practical purposes... nothing.
I don't think mutations apply unless a DAA is involved. I could be mistaken. I'm doing IFN/RIBA, since I was unfortunate enough to draw the placebo in this study.
I'll know in about 72 more weeks at my 6 month post-tx PCR whether it paid off or not :-)
RBW
Its something that only matters in certain instances Robert, like this, if you stay totally UND then of course you keep treating, but if you keep coming up with a few virons, then you have developed a resistant mutation at which point its better to cut your losses, allow the virus to return to wild type, and live to fight another day.
If you do develop a mutation able to survive the tx over repeated PCR's, then your chances of clearing go down signifigantly.
The trouble with >43 is therefore that it is never really telling you if you have a low level mutant, you could treat for years and still have it return when you quit. Since treatment is so hard on folks, it hardly makes sense to continue what is not going to work.
Before we had the option of a test this accurate it just made sense to continue treating with whatever results we could get, but to use a test like >43 when >1 is available, that would be like saying no thanks to a jet plane across the country and opting for a bicycle instead. Sure you may get there, but it will be a heck of a journey, needlessly long and painful.
The > 43 is fine when not treating, because VL will be high anyway, but not a good test when trying to decide whether to keep treating. Does this make sense now??
mb
If you do develop a mutation able to survive the tx over repeated PCR's, then your chances of clearing go down signifigantly.
The trouble with >43 is therefore that it is never really telling you if you have a low level mutant, you could treat for years and still have it return when you quit. Since treatment is so hard on folks, it hardly makes sense to continue what is not going to work.
Before we had the option of a test this accurate it just made sense to continue treating with whatever results we could get, but to use a test like >43 when >1 is available, that would be like saying no thanks to a jet plane across the country and opting for a bicycle instead. Sure you may get there, but it will be a heck of a journey, needlessly long and painful.
The > 43 is fine when not treating, because VL will be high anyway, but not a good test when trying to decide whether to keep treating. Does this make sense now??
mb
You guys are right it is the end of tx and 6 months later that matters... Keep up the fight.. Im rooting for you all every day...
I agree it's more info, but honestly, I have no idea what I'd do with it. I guess, as Bali pointed out, if I wasn't in a study I might be able to adjust things, and the info would be useful.
So in my situation, it just seems like a lot of unneeded stress worrying about OMG am I less than 25 or less than 15? It makes no difference to me. I'm either gonna clear, or I'm not.
Unfortunately, no matter how many tests we have, the final answer will not come for six months after treatment is complete.
:-)
RBW
So in my situation, it just seems like a lot of unneeded stress worrying about OMG am I less than 25 or less than 15? It makes no difference to me. I'm either gonna clear, or I'm not.
Unfortunately, no matter how many tests we have, the final answer will not come for six months after treatment is complete.
:-)
RBW
Good to hear from you. Congrats to your wk7 UND<43.
Great news and thanks for the info. Keep me posted.
VL test results are what it is all about in the end , isn`t it ?
I pretty much have the same philosophy. I only wish I knew all this in the beginning
I would have run the VL tests a little different. But as my luck had it right when I was
first becoming UND the NGI PCRs were not available..
My Hepatologist likes to run the Quest TMA Qualitative together with RT PCR<43
I on the other hand like the NGI PCRs .
Last results:
wk24 UND<2 PCR
wk34 UND<2 PCR
wk36 UND<43 PCR
wk36 UND <5 TMA
b
38 of 48
Great news and thanks for the info. Keep me posted.
VL test results are what it is all about in the end , isn`t it ?
I pretty much have the same philosophy. I only wish I knew all this in the beginning
I would have run the VL tests a little different. But as my luck had it right when I was
first becoming UND the NGI PCRs were not available..
My Hepatologist likes to run the Quest TMA Qualitative together with RT PCR<43
I on the other hand like the NGI PCRs .
Last results:
wk24 UND<2 PCR
wk34 UND<2 PCR
wk36 UND<43 PCR
wk36 UND <5 TMA
b
38 of 48
Bali : heading into the last few laps, eh - must be nice!
Since I also passed through that same stage of "what do you mean by und? " a few weeks back (my w7 was <43) I went back and revisited this issue and followed through on the suggestion I had given you above about contacting senior tech staff at the lab. Unfortunately the answers are not conclusive but I haven't given up yet. Here's what I've dug up so far:
- the COBAS Ampliprep/ COBAS Taqman (CAP/CTM) kit distributed by Roche Diagnostics is a very widely used (quite likely the most frequent) VL quantification assay. The package insert for the test is available on the FDA site:
http://www.accessdata.fda.gov/cdrh_docs/pdf6/P060030c.pdf
- one of the strengths of the test is minimal operator intervention which reduces contamination errors etc. As best I can make out after they draw the 5mL of blood into a violet-capped vial with EDTA anticoagulant, spin to extract serum, freeze and ship to the testing lab, there is no operator action between loading the specimen and retrieving the printout of results.
- page 41 of the package insert above details "Interpretation of Results". Basically (1) und (2) < 43 but detectable (3) within linear range of assay, 43 to 6.9E7 and (4) above range of assay. Page 46 confirms that, using dilutions from a World Health Org, (WHO) standard, the test detected concentrations as low as 18 IU/mL with 95% positivity. Table 4 on page 48 shows detection limits among clinical specimens and suggests the actual detection limit may be lower.
- so the conclusion is that at the time the operator finishes the CAP/CTM run and looks at the printout they can clearly tell the difference between und and unquantifiable. The question is how do different labs massage this in the final report given to the Dr. and patient. From a senior tech contact at Labcorp I confirmed that their results for this test, which on their menu is test 550080, distinguish between (1) and (2) by " <43 RNA not detected" and "<43 RNA detected". Note also that page 8 of the Labcorp Jan'09 newsletter describing test 550080 confirms the actual limit of detection is around 13 in serum:
https://www.labcorp.com/wps/portal/!ut/p/c0/04_SB8K8xLLM9MSSzPy8xBz9CP0os_hQV5NgQ09LYwMDS38nAyMv8zAjC6cgI3dLM_2CbEdFADN-4FM!/?WCM_PORTLET=PC_7_UE4S1I9300F7202JNDVEFE20G5_WCM&WCM_GLOBAL_CONTEXT=/wps/wcm/connect/labcorp+content/LabCorp/Provider/Resources/Lab+Horizons/LabHorizons+Archive
- I have not checked with Quest since I have not used them in this round. However my tests were done at a regional lab that also uses the CAP/CTM and I've been trying to get an answer as to how they distinguish (1) and (2) since their report does not include a "detected/not-detected" label. I noticed that the reference range (ie normal result) for their test is given as "< 43 -" that is, the lt 43 is followed by a dash and I suspect the presence absence of that dash indicates detection but I haven't confirmed this yet. Bottom line is that I think if you want a definite answer there's no substitute but to take this up with Quest.
RBW: when/whether to bother with sensitive tests is a regular source of argument here. I'm only interested in them at the low end of my vl decline. After my w7 lt 43 test I had NGI quants at w8, w10 and w12. A VL of 43 is still a lot of virus - that's 1.6 in log units and if your 2nd phase drop is around 0.5/wk that can be 3 weeks to complete und.
UND of course doesn't mean much - still millions of infected cells - but the slope of the decline says a lot about what's happening and how tx is working . So collecting data on the decline over those last weeks gives you information you wouldn't otherwise have. On the other hand past that point there's not much reason to bother - I'll probably do sensitive tests at w24 and eot to rule out persistent low-level vl (qual, no reason to pay for quant) but I'm not going to bother checking for intermediate blips.
Since I also passed through that same stage of "what do you mean by und? " a few weeks back (my w7 was <43) I went back and revisited this issue and followed through on the suggestion I had given you above about contacting senior tech staff at the lab. Unfortunately the answers are not conclusive but I haven't given up yet. Here's what I've dug up so far:
- the COBAS Ampliprep/ COBAS Taqman (CAP/CTM) kit distributed by Roche Diagnostics is a very widely used (quite likely the most frequent) VL quantification assay. The package insert for the test is available on the FDA site:
http://www.accessdata.fda.gov/cdrh_docs/pdf6/P060030c.pdf
- one of the strengths of the test is minimal operator intervention which reduces contamination errors etc. As best I can make out after they draw the 5mL of blood into a violet-capped vial with EDTA anticoagulant, spin to extract serum, freeze and ship to the testing lab, there is no operator action between loading the specimen and retrieving the printout of results.
- page 41 of the package insert above details "Interpretation of Results". Basically (1) und (2) < 43 but detectable (3) within linear range of assay, 43 to 6.9E7 and (4) above range of assay. Page 46 confirms that, using dilutions from a World Health Org, (WHO) standard, the test detected concentrations as low as 18 IU/mL with 95% positivity. Table 4 on page 48 shows detection limits among clinical specimens and suggests the actual detection limit may be lower.
- so the conclusion is that at the time the operator finishes the CAP/CTM run and looks at the printout they can clearly tell the difference between und and unquantifiable. The question is how do different labs massage this in the final report given to the Dr. and patient. From a senior tech contact at Labcorp I confirmed that their results for this test, which on their menu is test 550080, distinguish between (1) and (2) by " <43 RNA not detected" and "<43 RNA detected". Note also that page 8 of the Labcorp Jan'09 newsletter describing test 550080 confirms the actual limit of detection is around 13 in serum:
https://www.labcorp.com/wps/portal/!ut/p/c0/04_SB8K8xLLM9MSSzPy8xBz9CP0os_hQV5NgQ09LYwMDS38nAyMv8zAjC6cgI3dLM_2CbEdFADN-4FM!/?WCM_PORTLET=PC_7_UE4S1I9300F7202JNDVEFE20G5_WCM&WCM_GLOBAL_CONTEXT=/wps/wcm/connect/labcorp+content/LabCorp/Provider/Resources/Lab+Horizons/LabHorizons+Archive
- I have not checked with Quest since I have not used them in this round. However my tests were done at a regional lab that also uses the CAP/CTM and I've been trying to get an answer as to how they distinguish (1) and (2) since their report does not include a "detected/not-detected" label. I noticed that the reference range (ie normal result) for their test is given as "< 43 -" that is, the lt 43 is followed by a dash and I suspect the presence absence of that dash indicates detection but I haven't confirmed this yet. Bottom line is that I think if you want a definite answer there's no substitute but to take this up with Quest.
RBW: when/whether to bother with sensitive tests is a regular source of argument here. I'm only interested in them at the low end of my vl decline. After my w7 lt 43 test I had NGI quants at w8, w10 and w12. A VL of 43 is still a lot of virus - that's 1.6 in log units and if your 2nd phase drop is around 0.5/wk that can be 3 weeks to complete und.
UND of course doesn't mean much - still millions of infected cells - but the slope of the decline says a lot about what's happening and how tx is working . So collecting data on the decline over those last weeks gives you information you wouldn't otherwise have. On the other hand past that point there's not much reason to bother - I'll probably do sensitive tests at w24 and eot to rule out persistent low-level vl (qual, no reason to pay for quant) but I'm not going to bother checking for intermediate blips.
sorry to hear you have such a hard time to get labs done.
There is no secret. Guess I chose cooperative doctors.
BTW if they were not cooperative I would go looking to find one
that is. There is nothing as close and personal as your own health.
There is no secret. Guess I chose cooperative doctors.
BTW if they were not cooperative I would go looking to find one
that is. There is nothing as close and personal as your own health.
I'm interested in the HOW you get all these tests. I finished tx 11 weeks ago and want a PCR next week but I'll have to fight to get it. My doctor wants to wait till 6 months have passed. Do you have a cooperative doctor, or is there some secret to getting the test you could share? -- Carol
"if you go in the medhelp archives and read about HRs posts and PCR tests
you will understand why I find it difficult to chill.
I want to be as UND as I can be and <43 does not satisfy anymore. "
Why? Will it change your treatment plan? I guess I'm missing the point of the incessant testing. It's not going to change the final result. You either will SVR, or you won't.
If the results change the treatment plan, please elaborate. Perhaps there is something I'm missing in my plan that I could benefit from.
Thanks
Robert
you will understand why I find it difficult to chill.
I want to be as UND as I can be and <43 does not satisfy anymore. "
Why? Will it change your treatment plan? I guess I'm missing the point of the incessant testing. It's not going to change the final result. You either will SVR, or you won't.
If the results change the treatment plan, please elaborate. Perhaps there is something I'm missing in my plan that I could benefit from.
Thanks
Robert
Hi Willing,
How are you ?
Not sure if you remember but some 30wks ago my wk6 PCR by Quest gave me a
in range result of <43. I repeated it @ wk9 with the LabCorp PCR and it gave me
UND<43 , HCV RNA Not detected result.
You mentioned at the time that the Quest PCR was missing the "undetectable" label and therefore still detectable <43.
Now at wk36 I ran the same Quest PCR <43 together (same draw) with a Qual TMA< 5.
The TMA Qual was reported as UND and the Quest PCR again as in range <43 IU.
In conclusion my wk6 PCR was not missing any UND label but because it is a Quant
it just gets reported as in or out of range. Unlike the LabCorp RT PCR<43.
Cheers
b
How are you ?
Not sure if you remember but some 30wks ago my wk6 PCR by Quest gave me a
in range result of <43. I repeated it @ wk9 with the LabCorp PCR and it gave me
UND<43 , HCV RNA Not detected result.
You mentioned at the time that the Quest PCR was missing the "undetectable" label and therefore still detectable <43.
Now at wk36 I ran the same Quest PCR <43 together (same draw) with a Qual TMA< 5.
The TMA Qual was reported as UND and the Quest PCR again as in range <43 IU.
In conclusion my wk6 PCR was not missing any UND label but because it is a Quant
it just gets reported as in or out of range. Unlike the LabCorp RT PCR<43.
Cheers
b
thanks Dave,
the longer you stay on this stuff the ruffer it gets. 2 more weeks and it is
halftime for me. Something tells me round 2 is where the real work begins.
b
the longer you stay on this stuff the ruffer it gets. 2 more weeks and it is
halftime for me. Something tells me round 2 is where the real work begins.
b
I recently has the NGI test done and it took 2 full weeks to get the results back. Our plan now is to have regular labcorp PCRs done and substitute a monthly or bimonthly NGI test once reaching UND.
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