pegintron vs pegasys

[Dee1956]

Hello, I am about to start treatment for the 2nd time.  The first time (2008) was a trial with Roche 1626 polymerase inhibitor, Pegasys and Ribavarin.  I was UND between 7 or 8 weeks, relapsed 6 weeks after being pulled from tx at 43 of 48 weeks as the trial drug was too harsh on my  system.  Back then they refused to give me rescue drugs so I had no choice.  I have diabetes which may have contributed to my relapse, during tx my sugar was so low I stopped checking it, DUH!
I am a Geno 1A 2/4 VL 350K

I am waiting for the new treatment to be authorized by my insurance co.   This time the doc wants me to go on Pegintron 150mcg I have searched this forum to try to find out what the difference is between Pegasys 180 mcg and Pegintron 150mcg.  I found a few posts from 2006 but am hoping for more/newer info.  I was on Pegasys the first time so I guess I am not as afraid of it as I am the Pegintron.   I am 5" 5 and weigh 140.  I have learned so much from so many of you since 2007;  I am very grateful.   I am hoping no one minds me asking this question. Since going on Metformin my VL has gone from 7m to 340K which I hope is a good thing.
So all you wonderful people, can you tell me the difference between the two interferon's?
Thanking you in advance and hoping this new tx works for everyone.
Dee

[drsyednaveed]

i think pegintron is much more better than pegysis.
beacause pegintron is weight base dose it is given according to body weight
pegysis is fixed dose
pegintron has 69 litre volume of distribution while pegysis has 7 to 14 litre
pegintron has 28 percent viral activity while pegysis has only 7 percnt viral activity.
pegintron has peg size 12 kd so detachment is easy while pegysis has 40 kd heavy peg . that effects its efficacy

[willing]

Here is  a recent review comparing the two which includes an overview of available data through last year:

http://www.ncbi.nlm.nih.gov/pubmed/20108989

One of the two studies that detected a statistically significant advantage to 2a is

http://www.ncbi.nlm.nih.gov/pubmed/19852964

The effect of stronger welding of a bigger antifreeze cannonball to the protein described in the review "The branched, 40 kDa PEG chain of peginterferon-alpha-2a is covalently attached via stable amide bonds to lysine residues of interferon-alpha-2a, and circulates as an intact molecule. " is clearly apparent in  the yo-yo pattern of circulating of 2b in :

http://www.medhelp.org/user_photos/show/168497

As far as I know there is no data showing greater efficacy for 2b

[willing]

Check with desrt - he posted an interesting study a while  back showing a bigger advantage in favor of 2a over 2b than commonly acknowledged. The conventional wisdom is that there's not much difference in effectiveness:
http://www.ncbi.nlm.nih.gov/pubmed/18422960
though the 2b weight-based approach provides more flexibility in dosing.  Challenging the insurance seems the right call - that's a decision for you and your Dr. not for them. Overall though, I doubt you're going to make a  mistake with either.

Also re the rbv pre-dosing, expired meds are always a bad idea, but once you have the rx  in hand the start dates (together or rbv first )  are up to you. Laying in at least a month's tx supply before taking anything is a good idea. UPS/Fedex, the inscos, and Dr's office will conspire to cause you stress regarding a continuous supply during tx and the month buffer provides some protection.

[frijole]

streamline
I goofed - the 2 is next to the 3 on the computer (ha ha).  No, I am grade 3 stage 3 & 4, and the doctor said from the sample it was about half and half (and also about half steatosis) and that since I had stage 4, they would have to treat it as cirrhotic (which, for purposed of the Victrelis means the full 48 weeks, no response guided therapy)

evangelin - i know exactly what you are saying.  Yesterday I wrote a letter to my insurance company with a copy to my doctor and faxed them both yesterday to prove my relapse with Pegasys.  Now I am having big second thoughts.  If Pegasys seems to have a slight edge, according to the studies I looked at, and it is easier on the system, why do the PegIntron?????  I may call my doctor and do the same thing you did. -- in fact, I just left a message with his medical assistant!!!!
frjiole

[evangelin]

Remember Cowriter?  If I understand correctly, she works with HCV patients and I believe she has said that although it is harder to take,  the recovery from Peg-intron is faster than Pegasys.  She is at the Nomads forum more frequently but she pops by here now and then and you could probably PM her about that.  It might help you in your decision making.
I have been up and down on the issue.  The PA ordered the Peg-intron but I went home and started having flashbacks of the horrible SX Joe had.  I called them and asked them to change to Pegasys.  I could tell they were put out about it and no doubt think  me a royal pain.  It made me feel bad and embarassed, but not bad enough to let Joe suffer through that again.  I am settled to the fact that he is taking Pegasys because if I changed my mind again, they would probably tell us to go away and never come back.  :>)  They like Joe, it is me that they might ban. :>)
Ev

[streamline569]

Just curious, how did they tell half of you liver was stage 2 and half stage 4. I'll have to ask my doctor about that one.

[frijole]

Should have said, half my liver is stage 3 and half is stage 4.

I am second guessing the hepo now about the PegIntron.  After researching this weekend and reading posts I think I would rather do the Pegasys.

Evangelin and Mike, I appreciate your candid opinions about the two.

frijole

[willbb]

Personally ,I will be doing Pegintron .for my next treatment if for the only reason .like yourself had a failed attempt with Pegasys the first time.

However I think  frijole hit the nail on the head when  she said:
I think the deciding factor is going to be the protease inhibitor

Good luck with the the new treatment....

Will

[Dee1956]

Thank you again for your great replies, perhaps my docs thinking is that I relapsed with Pegasys so he wants to use Pegnitron to better my chances of SVR.  Oh going on Incivek
Thank you again for helping me, I am grateful to everyone
D

[frijole]

Dee
I also have been dx with cirrhosis since last I treated.  It is just beginning stages I think - no ascites, no lesions per my ultrasound Wednesday, but about half my liver is stage 2 fibrosis and half is stage 4 and there are indications of nodules forming.  This new dx changes the picture and my hepo also said that it will be harder to reach SVR.  Which PI are you taking?  My preference is Victrelis and that looks like the one that will make the least amount of waves with my insurance company.  I never dose reduced last time but used neupogen and procrit.

[Dee1956]

Thanks so much for your information.  I wonder if that is why my doctor is putting me on pegintron.  He said that with cirrhosis I would have a hard time getting to SVR.  It looks like he is putting me on 800 mg riba, I took 1000 last time though suffered dose reductions from anemia, neutropenia, low lymphocytes, etc.  This time I can at least have rescue drugs, maybe that will make all the difference.
Thank you again
D

[Dee1956]

Thank you so very much for your post, it means a lot to me that people have responded and your answer helps me very much all of the answers help so much I am grateful
I had a hard time with the Pegasys and don't wish to take anything stronger but I want it to work this time.  I am going to feel like hell so I want it to be for the end goal of SVR
Thanks again
Dee

[frijole]

I just can't see that it is going to make much difference which INF is used.  Pegasys seems to have the edge and from what many people say, it is easier to handle.  I know I handled the Pegasys pretty well back in 2005/06.  I don't know why my doctor ordered the PegIntron but probably because I failed treatment with Pegasys and logic says use the other and in this matter, I must rely on the judgement of the hepo.

I think the deciding factor is going to be the protease inhibitor.  My mind just gets mucky with all this.  I am going to send my insurance company proof of my failure for Pegasys which is their reason for denial, but in the long run, I just want to get started and don't really care.

frjiole

[frijole]

A very timely thread.  I have been studying this myself this weekend since my doctor rx’ed PegIntron and the insco has denied it.  I too have failed treatment previously with Pegasys.

Pulling apart the IDEAL study which was funded by Schering Plough (makers of PegIntron) (presented 2008) – there were 3070 treatment naïve patients –genotype 1--

  Overall – SVR – Pegasys 41%,   PegIntron (1.5mcg/kg/wk)  40%

   For patients >80% adherance , SVR – PegIntron – 70%,  Pegasys – 61%

   Relapse -  Pegasys 32%, PegIntron 24%

Italian Study –  included all 4 genotypes

  Overall SVR – Pegasys 68%, PegIntron 54%
                                  Genotype 2-3 – Pegasys 88%. PegIntron 75%
                                  Genotypes 1-4 – Pegasys -55%,  PegIntron 40%
                                   VL 600,000  Pegasys 68% PegIntron 65%

The PROBE study –(Italy & Germany)(presented 2008)    7445 patients of which 1341 were geno 1,treatment naïve       - seems to be mostly a study about factors that predict SVR , only 1 of which was Peg INf a-2a or 2b

    SVR in Geno 1 - Pegasys 41%, PegIntron 34%              
    
  
COMPARE study –(2004) no ribavirin

     No SVR data

The German Study – PRACTICE (2000-2007) (sponsored by Roche makers of Pegasys) – retrospective observational study

     SVR – Pegasys 52.9%, PegIntron 50.5%
         Geno 1  Pegasys -48.7%, PegIntron 44.1%
          Geno 2/3 Pegasys 78.7%, PegIntron 76%

http://www.medhelp.org/posts/Hepatitis-C/Pegasys-v-PegIntron/show/452190

This is a pretty good thread from 2008 – one comment by desrt is poignant to me.  It is regarding retreating with Pegasys every 5 days after relapse with PegIntron

“interferon has never been dosed by what's effective - it's dosed by what the human body can tolerate”. So I would take what I could tolerate.

[Dee1956]

Morning, I wanted to thank each of you for your answers, they were all good and really helped me to decide to discuss with the doc.  I would like to choose the lesser of the evils with the best chance of SVR.  I know I am going to feel bad from my previous exposure however I feel bad now so I hope it will get better
Thanks again for the great answers
D

[Dee1956]

Ev, thank you so very much for your response, I try to look everything up on the forum rather than asking a question but could not find the answer I was looking for, again, thank you
Dee

[Dee1956]

Hi, thank you so very much for this information, my fear is getting less and less, off to read your links, thanks again!
I feel so much better!
Dee

[evangelin]

The only comment I would have is that my husband has taken Peg-intron, Infergen and Pegasys and Peg-intron had more harsh SX than the other two, at least for him.  His depression and personality changes were much more pronounced with Peg-intron.  It made for a really bad time for our whole family.  Nothing with these drugs seems to hold true for everyone,but that was our experience.  Others have described Infergen as terrible but after living through the Peg-intron, Infergen didn't seem so bad.  Pegasys was the easier of the three, for Joe.  (Notice that I didn't say Pegasys was fun, just a bit easier but you already know about that. )
Best Wishes,
Ev

[flcyclist]

Here's a few studies for further reading.  

In the COMPARE study, PEG-INTRON demonstrated significantly greater antiviral activity vs. PEGASYS at week one, with greater maximum antiviral activity (P<0.001) and greater cumulative antiviral activity (P=0.017); and at week 4, with greater maximum antiviral activity (P<0.001) and greater cumulative antiviral activity (P<0.001). The slope of the viral load reduction for PEG-INTRON was greater over the eight-week study duration (P<0.002). In addition, 72 percent of patients in the PEG-INTRON arm achieved at least a 2.0 Log10 reduction in viral load as compared to 44 percent of patients in the PEGASYS arm during the study (p=0.09).

http://www.medicalnewstoday.com/releases/15692.php

http://www.natap.org/2008/EASL/EASL_86.htm

http://www.aidsmeds.com/articles/hiv_pegasys_pegintron_1667_17850.shtml

[Dee1956]

Thank you so much for the definition, the chuckle and your informative opinion, I could not ask for a better answer.  I really appreciate your response.
I am really afraid to tx again but I don't like the side effects from HCV either, they aren't going to go away on their own.  
D

[desrt]

"PEG-interferon alpha is a pegylated interferon composed of 165 amino acids. The PEG (polyethylene glycol) protects the molecule from proteolytic breakdown and increases the biological half-life of the interferon protein"
http://en.wikipedia.org/wiki/Peginterferon_alfa-2b

" In Pegasys, a large, branched, mobile PEG is attached to the interferon alfa-2a molecule, providing a selectively protective barrier against rapid absorption, metabolism and elimination"
http://www.medilexicon.com/drugs/pegasys.php

Well, you asked.

When Pegasys became available in 2002, evryone thought it was going to knock PegIntron out of the market because its branched PEG molecule gave it a longer half-life and thus a more constant level of IFN in your system.
Trouble is that in head to head comparisons, the two drugs always seem to come out about even. To me, this implies that Pegasys (PegIFN alpha 2a) has a better time release but that PegIntron (PegIFN alpha 2b) actually has a 'stronger' form of interferon.
But that's just me theorizing.