VX 770-will it help us?

missT

Member
So I am super excited about the VX770 because from the internet research I have done it seems that it "may" just help us too. The G mutation is a class 3 and R117H is a class 4 but I think from my understanding they tested the G mutation because of the size of the population. G has 4% and R117H has 0.8-2%. It seems that the VX770 did "cure" the R117H in test tubes but has not been tested on humans with the mutation. I am thinking that once Vertex goes to the FDA they will include the R117H mutation so we can benefit from the drug too! Can anyone please tell me if they think I am right or wrong. Am I being too optimistc here? Anyone on the VX770 have any input? I asked my CF clinc today and they seemed to agree with me but did not want to give me too much hope.
 

missT

Member
So I am super excited about the VX770 because from the internet research I have done it seems that it "may" just help us too. The G mutation is a class 3 and R117H is a class 4 but I think from my understanding they tested the G mutation because of the size of the population. G has 4% and R117H has 0.8-2%. It seems that the VX770 did "cure" the R117H in test tubes but has not been tested on humans with the mutation. I am thinking that once Vertex goes to the FDA they will include the R117H mutation so we can benefit from the drug too! Can anyone please tell me if they think I am right or wrong. Am I being too optimistc here? Anyone on the VX770 have any input? I asked my CF clinc today and they seemed to agree with me but did not want to give me too much hope.
 

missT

Member
So I am super excited about the VX770 because from the internet research I have done it seems that it "may" just help us too. The G mutation is a class 3 and R117H is a class 4 but I think from my understanding they tested the G mutation because of the size of the population. G has 4% and R117H has 0.8-2%. It seems that the VX770 did "cure" the R117H in test tubes but has not been tested on humans with the mutation. I am thinking that once Vertex goes to the FDA they will include the R117H mutation so we can benefit from the drug too! Can anyone please tell me if they think I am right or wrong. Am I being too optimistc here? Anyone on the VX770 have any input? I asked my CF clinc today and they seemed to agree with me but did not want to give me too much hope.
 
M

marcijo

Guest
I definitely hope you are right!! My CF doctor seems to think it probably will as class 3 and 4 are similar in the issues that are wrong with the channel...from what I remember. I am hoping and praying that this is the case!
 
M

marcijo

Guest
I definitely hope you are right!! My CF doctor seems to think it probably will as class 3 and 4 are similar in the issues that are wrong with the channel...from what I remember. I am hoping and praying that this is the case!
 
M

marcijo

Guest
I definitely hope you are right!! My CF doctor seems to think it probably will as class 3 and 4 are similar in the issues that are wrong with the channel...from what I remember. I am hoping and praying that this is the case!
 
M

marcijo

Guest
I did find this: VX-770 is a potent and selective potentiator of wild-type, G551D, F508del, and R117H forms of human CFTR. Based on in vitro studies and pharmacologic, pharmacokinetic (PK), and safety profiles, VX-770 has been selected for clinical development as a possible treatment for patients with CF.

It was in this article: <a target=_blank class=ftalternatingbarlinklarge href="http://clinicaltrialsfeeds.org/clinical-trials/show/NCT01262352">http://clinicaltrialsfeeds.org...rials/show/NCT01262352</a>
 
M

marcijo

Guest
I did find this: VX-770 is a potent and selective potentiator of wild-type, G551D, F508del, and R117H forms of human CFTR. Based on in vitro studies and pharmacologic, pharmacokinetic (PK), and safety profiles, VX-770 has been selected for clinical development as a possible treatment for patients with CF.

It was in this article: <a target=_blank class=ftalternatingbarlinklarge href="http://clinicaltrialsfeeds.org/clinical-trials/show/NCT01262352">http://clinicaltrialsfeeds.org...rials/show/NCT01262352</a>
 
M

marcijo

Guest
I did find this: VX-770 is a potent and selective potentiator of wild-type, G551D, F508del, and R117H forms of human CFTR. Based on in vitro studies and pharmacologic, pharmacokinetic (PK), and safety profiles, VX-770 has been selected for clinical development as a possible treatment for patients with CF.
<br />
<br />It was in this article: <a target=_blank class=ftalternatingbarlinklarge href="http://clinicaltrialsfeeds.org/clinical-trials/show/NCT01262352">http://clinicaltrialsfeeds.org...rials/show/NCT01262352</a>
 
M

marcijo

Guest
Ok-one more...I also found this..it's an older article but it tells how G551D and R117H are similar:

Potentiator drugs have also reached phase 1 and 2 clinical trials. This set of drugs targets mutated CFTR present in the apical membrane and is designed to augment the ion channel function of these proteins. The CFTR mutations that are especially amenable to this approach are the mutated channels that already reach the membrane but display less functional activity than wild-type. Two such mutations are R117H and G551D. R117H is present in 0.8 - 2% of the CF population (The Cystic Fibrosis Genetic Analysis Consortium) and results in mutated but mature CFTR protein that demonstrates a lower open probability (PO ~0.1) than wild type CFTR [PO ~0.35 - 0.40 [35, 36]. G551D also reaches the plasma membrane as a mature protein. However, it demonstrates severely diminished open probability, PO ~0.04 [37], and is present in 2 - 6% of CF patients (The Cystic Fibrosis Genetic Analysis Consortium). The plant isoflavone genistein, a phytoestrogen, has been well documented [37 - 39], at concentrations of ~50 µM or greater, to activate mutated CFTR in the epithelium. It is, however, difficult to achieve these concentrations, since genistein bioavailability by oral administration is very low [40].
Consequently, there has been a search to find more potent and specific CFTR potentiators than genistein. Two compounds are in development by Vertex Pharmaceuticals, in collaboration with Cystic Fibrosis Foundation Therapeutics, and they are currently in phase 1 and phase 2 clinical trials. Oral VX-770 is in phase 2 trials in G551D genotype CF patients. VX-809 is currently in phase 1A trials and expected to enter phase 1B trials in mid 2008. In vitro patch clamp studies, carried out on CFTR expressed in Fisher Rat Thyroid cells, have demonstrated that VX-770 increases ?F508 PO from 0.11 ± 0.05 to 0.45 ± 0.06, and G551D PO from 0.08 ± 0.03 to 0.52 ± 0.19 [41]**. These data suggest that VX-770 can increase ?F508 and G551D PO to values in the range reported for wild type CFTR. Chloride secretion across Fisher Rat Thyroid monolayers over-expressing ?F508 in Ussing chambers in response to VX770 was somewhat less robust, with an increase above a very low basal short circuit current of ~2 fold [41]. The data are not surprising, since the quantity of ?F508 CFTR protein in the membrane is presumably small. However, the increase in G551D current was 14-fold, representing 65% of the current carried by wild type CFTR in this system. Importantly, VX-770 is more potent than genistein, with an EC50 of ~600 nM, and is reported to be orally bioavailable [41]. Likely, for ?F508 CF patients, dual therapy will be required, with corrector to traffic mutated CFTR protein to the apical membrane and potentiators such as VX-770 to stimulate activation.

Here's the link to the complete article: <a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/</a>
 
M

marcijo

Guest
Ok-one more...I also found this..it's an older article but it tells how G551D and R117H are similar:

Potentiator drugs have also reached phase 1 and 2 clinical trials. This set of drugs targets mutated CFTR present in the apical membrane and is designed to augment the ion channel function of these proteins. The CFTR mutations that are especially amenable to this approach are the mutated channels that already reach the membrane but display less functional activity than wild-type. Two such mutations are R117H and G551D. R117H is present in 0.8 - 2% of the CF population (The Cystic Fibrosis Genetic Analysis Consortium) and results in mutated but mature CFTR protein that demonstrates a lower open probability (PO ~0.1) than wild type CFTR [PO ~0.35 - 0.40 [35, 36]. G551D also reaches the plasma membrane as a mature protein. However, it demonstrates severely diminished open probability, PO ~0.04 [37], and is present in 2 - 6% of CF patients (The Cystic Fibrosis Genetic Analysis Consortium). The plant isoflavone genistein, a phytoestrogen, has been well documented [37 - 39], at concentrations of ~50 µM or greater, to activate mutated CFTR in the epithelium. It is, however, difficult to achieve these concentrations, since genistein bioavailability by oral administration is very low [40].
Consequently, there has been a search to find more potent and specific CFTR potentiators than genistein. Two compounds are in development by Vertex Pharmaceuticals, in collaboration with Cystic Fibrosis Foundation Therapeutics, and they are currently in phase 1 and phase 2 clinical trials. Oral VX-770 is in phase 2 trials in G551D genotype CF patients. VX-809 is currently in phase 1A trials and expected to enter phase 1B trials in mid 2008. In vitro patch clamp studies, carried out on CFTR expressed in Fisher Rat Thyroid cells, have demonstrated that VX-770 increases ?F508 PO from 0.11 ± 0.05 to 0.45 ± 0.06, and G551D PO from 0.08 ± 0.03 to 0.52 ± 0.19 [41]**. These data suggest that VX-770 can increase ?F508 and G551D PO to values in the range reported for wild type CFTR. Chloride secretion across Fisher Rat Thyroid monolayers over-expressing ?F508 in Ussing chambers in response to VX770 was somewhat less robust, with an increase above a very low basal short circuit current of ~2 fold [41]. The data are not surprising, since the quantity of ?F508 CFTR protein in the membrane is presumably small. However, the increase in G551D current was 14-fold, representing 65% of the current carried by wild type CFTR in this system. Importantly, VX-770 is more potent than genistein, with an EC50 of ~600 nM, and is reported to be orally bioavailable [41]. Likely, for ?F508 CF patients, dual therapy will be required, with corrector to traffic mutated CFTR protein to the apical membrane and potentiators such as VX-770 to stimulate activation.

Here's the link to the complete article: <a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/</a>
 
M

marcijo

Guest
Ok-one more...I also found this..it's an older article but it tells how G551D and R117H are similar:
<br />
<br />Potentiator drugs have also reached phase 1 and 2 clinical trials. This set of drugs targets mutated CFTR present in the apical membrane and is designed to augment the ion channel function of these proteins. The CFTR mutations that are especially amenable to this approach are the mutated channels that already reach the membrane but display less functional activity than wild-type. Two such mutations are R117H and G551D. R117H is present in 0.8 - 2% of the CF population (The Cystic Fibrosis Genetic Analysis Consortium) and results in mutated but mature CFTR protein that demonstrates a lower open probability (PO ~0.1) than wild type CFTR [PO ~0.35 - 0.40 [35, 36]. G551D also reaches the plasma membrane as a mature protein. However, it demonstrates severely diminished open probability, PO ~0.04 [37], and is present in 2 - 6% of CF patients (The Cystic Fibrosis Genetic Analysis Consortium). The plant isoflavone genistein, a phytoestrogen, has been well documented [37 - 39], at concentrations of ~50 µM or greater, to activate mutated CFTR in the epithelium. It is, however, difficult to achieve these concentrations, since genistein bioavailability by oral administration is very low [40].
<br />Consequently, there has been a search to find more potent and specific CFTR potentiators than genistein. Two compounds are in development by Vertex Pharmaceuticals, in collaboration with Cystic Fibrosis Foundation Therapeutics, and they are currently in phase 1 and phase 2 clinical trials. Oral VX-770 is in phase 2 trials in G551D genotype CF patients. VX-809 is currently in phase 1A trials and expected to enter phase 1B trials in mid 2008. In vitro patch clamp studies, carried out on CFTR expressed in Fisher Rat Thyroid cells, have demonstrated that VX-770 increases ?F508 PO from 0.11 ± 0.05 to 0.45 ± 0.06, and G551D PO from 0.08 ± 0.03 to 0.52 ± 0.19 [41]**. These data suggest that VX-770 can increase ?F508 and G551D PO to values in the range reported for wild type CFTR. Chloride secretion across Fisher Rat Thyroid monolayers over-expressing ?F508 in Ussing chambers in response to VX770 was somewhat less robust, with an increase above a very low basal short circuit current of ~2 fold [41]. The data are not surprising, since the quantity of ?F508 CFTR protein in the membrane is presumably small. However, the increase in G551D current was 14-fold, representing 65% of the current carried by wild type CFTR in this system. Importantly, VX-770 is more potent than genistein, with an EC50 of ~600 nM, and is reported to be orally bioavailable [41]. Likely, for ?F508 CF patients, dual therapy will be required, with corrector to traffic mutated CFTR protein to the apical membrane and potentiators such as VX-770 to stimulate activation.
<br />
<br />Here's the link to the complete article: <a target=_blank class=ftalternatingbarlinklarge href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2517236/</a>
 

missT

Member
Hi Marci, I did read those articles. I am not a doctor but the two mutations seem rather similiar. It almost seems to me like our mutation has a little better of a chance once it gets to the plasma membrane. I am just hoping that Vertex knows this already and includes our mutation without clinical trial testing. Where do you think your R117H mutation is from? I am half Irish so I am pretty convinced it is from my Irish side of the family.
 

missT

Member
Hi Marci, I did read those articles. I am not a doctor but the two mutations seem rather similiar. It almost seems to me like our mutation has a little better of a chance once it gets to the plasma membrane. I am just hoping that Vertex knows this already and includes our mutation without clinical trial testing. Where do you think your R117H mutation is from? I am half Irish so I am pretty convinced it is from my Irish side of the family.
 

missT

Member
Hi Marci, I did read those articles. I am not a doctor but the two mutations seem rather similiar. It almost seems to me like our mutation has a little better of a chance once it gets to the plasma membrane. I am just hoping that Vertex knows this already and includes our mutation without clinical trial testing. Where do you think your R117H mutation is from? I am half Irish so I am pretty convinced it is from my Irish side of the family.
 

sunflower

New member
HiVX 770-will it help us?

Hi, I hoping someone can point me in the right direction, I am looking to find out the different type of CF mutations list what grade of CF genes I have.

I have my fingers crossed and my DR said VX-770 looks very promising but with me having DF 508 it wouldn't work and we would need two tablets VX770 - 809. I know they have started trials and really hope it works I just have to sit back and wait and see what happens.
So delighted and being positive about Vertex.

40 yrso old
DF-508- P67L
ABPA-ASTHMA, Psuedomonas
Husband a carrier of DF508 and waiting on our foster child to arrive...so happy...x
 

sunflower

New member
HiVX 770-will it help us?

Hi, I hoping someone can point me in the right direction, I am looking to find out the different type of CF mutations list what grade of CF genes I have.

I have my fingers crossed and my DR said VX-770 looks very promising but with me having DF 508 it wouldn't work and we would need two tablets VX770 - 809. I know they have started trials and really hope it works I just have to sit back and wait and see what happens.
So delighted and being positive about Vertex.

40 yrso old
DF-508- P67L
ABPA-ASTHMA, Psuedomonas
Husband a carrier of DF508 and waiting on our foster child to arrive...so happy...x
 

sunflower

New member
HiVX 770-will it help us?

Hi, I hoping someone can point me in the right direction, I am looking to find out the different type of CF mutations list what grade of CF genes I have.
<br />
<br />I have my fingers crossed and my DR said VX-770 looks very promising but with me having DF 508 it wouldn't work and we would need two tablets VX770 - 809. I know they have started trials and really hope it works I just have to sit back and wait and see what happens.
<br />So delighted and being positive about Vertex.
<br />
<br />40 yrso old
<br />DF-508- P67L
<br />ABPA-ASTHMA, Psuedomonas
<br />Husband a carrier of DF508 and waiting on our foster child to arrive...so happy...x
 
M

marcijo

Guest
MissT-that is exactly the conclusion I came too by reading the articles-let's hope we are right!

That is too funny about the R117H - my grandmpa was from Ireland so I am 1/4 Irish-I am pretty sure that is who I got the R117H from. My parents were never tested to see what gene they carry-otherwise I would know.

My other gene, the DF508, is more common in Eastern European people-and my grandma (oon the other side) came from Holland. That's my theory from where I got the genes, anyways!

I too am hoping that we can start the VX 770 right away......

Sunflower-I know the DF508 is a class 2....I'm not sure about your other gene though. I have come across something in the past that lists the different classes and a few examples some genes that are in that class....I will see if I can find it.

Edited to add:: I just found that your other gene is either a class 4 or class 5: These mild CFTR gene mutations are associated with pancreatic sufficiency and tend to be class 4 through 5 mutations: R117H, R334W, R347P, L206W, and P67L....taken from this article: <a target=_blank class=ftalternatingbarlinklarge href="http://jama.ama-assn.org/content/281/23/2217.full">http://jama.ama-assn.org/content/281/23/2217.full</a>
 
M

marcijo

Guest
MissT-that is exactly the conclusion I came too by reading the articles-let's hope we are right!

That is too funny about the R117H - my grandmpa was from Ireland so I am 1/4 Irish-I am pretty sure that is who I got the R117H from. My parents were never tested to see what gene they carry-otherwise I would know.

My other gene, the DF508, is more common in Eastern European people-and my grandma (oon the other side) came from Holland. That's my theory from where I got the genes, anyways!

I too am hoping that we can start the VX 770 right away......

Sunflower-I know the DF508 is a class 2....I'm not sure about your other gene though. I have come across something in the past that lists the different classes and a few examples some genes that are in that class....I will see if I can find it.

Edited to add:: I just found that your other gene is either a class 4 or class 5: These mild CFTR gene mutations are associated with pancreatic sufficiency and tend to be class 4 through 5 mutations: R117H, R334W, R347P, L206W, and P67L....taken from this article: <a target=_blank class=ftalternatingbarlinklarge href="http://jama.ama-assn.org/content/281/23/2217.full">http://jama.ama-assn.org/content/281/23/2217.full</a>
 
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