Pegasys (alpha 2a) vs Pegintron (alpha 2b)

[Marcia2202]

I have been trying to find some solid information on this subject. The only thing I found was this following info from another forum. Does anyone know which one is more suitable for which GT.

Thanks, Marcia

"Here is some new information for people who may have a choice of which
type of interferon they use for combo tx.  The results were derived from a
combination of studies (meta-analysis) of 824 patients. For genotype 1,
the
difference between Pegintron (alpha 2b Schering) and Pegasys (alpha 2a
Roche) was statistically significant and, IMO, a pretty big difference:
49% of  patients using Pegintron achieved SVR, compared to only 36% of
patients using Pegasys.  Differences between the 2 drugs for genos 2 and 3
weren't very remarkable.   (Note SVR = Sustained Viral Response = absence
of detectable HCV RNA 6 months after end of tx)."

[Marcia2202]

Thanks so much. I think I'll go for the pegasys, if possible.  Not too keen on more sx than necessary... Am curious what the heps are going to suggest.
I don't think I want to wait another year or so for tx, though. (until the new drugs have been approved) I have such bad fatigue and brain fog already, I really don't want to drag myself around for that long before going into tx.

Marcia

[FlGuy]

I agree with Andiamo

[NashPred]

I'm glad to hear of less sides with Pegasys. I have 1 more PegIntron injection and then the Dr. is changing me to Pegasys.

PegIntron has not been too friendly to me these first 3 weeks.

[Andiamo1]

I have taken both - unfortunately!  For me, the side effects of Pegasys were noticeably less than those of Pegintron.

Good luck with all your tests.  My own opinion is that it is better to wait for the new drugs if you have the time and inclination.

Eric

[Marcia2202]

The first study mikesimon posted and the study you posted both say that they observed no real difference. That is actually very comforting, it would leave me with not having to chose 'sides' with either possibility. In another thread,someone suggested that it would be best to go with what your hepatologist had the most experience with.

Thanks for all your inputs!!!

Marcia

[drofi]

Different sponsors = different results of studies 2a vs. 2b .
Have a close look to the ribavirin concentrations, if you read the studies. It is not a surpise to find better results in studies comparing different riba doses :-)
There are little investigator initiated studies, most are pharmastudies.
Perhaps the 2a has an advantage from the longer halflife and 2b has an advantage from the smaller size and better distribution in the body.
In sum, they are both similar in respect to SVR.

Best regards, drofi

Drugs. 2008;68(6):791-801.

Early and Sustained Virological Response in Non-Responders with Chronic Hepatitis C : A Randomized Open-Label Study of Pegylated Interferon-alpha-2a versus Pegylated Interferon-alpha-2b.

Scotto G, Fazio V, Fornabaio C, Tartaglia A, Di Tullio R, Saracino A, Angarano G.

Clinic of Infectious Diseases, University of Foggia, Foggia, Italy.

OBJECTIVES: The purpose of this randomized open-label study was to assess the efficacy of treatment with pegylated interferon-alpha-2a versus pegylated interferon-alpha-2b, both plus ribavirin, in inducing early and sustained virological response (EVR and SVR) in chronic hepatitis C non-responders. PATIENTS AND METHODS: A total of 108 patients with chronic hepatitis C who were non-responders to previous combined therapy (standard interferon-alpha plus ribavirin for>/=3 months) were enrolled and equally randomized into two groups in this intention-to-treat analysis. The patients exhibited similar baseline features. One group received subcutaneous pegylated interferon-alpha-2a 180 mug once weekly, while the other was treated with subcutaneous pegylated interferon-alpha-2b 1.5 mug/kg once weekly. Ribavirin 15 mg/kg/day was included in both protocols. Treatment duration for EVR was 12 weeks. Patients who demonstrated non-detectable hepatitis C virus (HCV) RNA or a>/=2 log(10) reduction in viral load at week 12 continued therapy up to 48 weeks, with assessments every 3 months during a follow-up of 24 weeks. RESULTS: All patients in both groups completed the EVR study, then seven patients receiving pegylated interferon-alpha-2a and seven patients receiving pegylated interferon-alpha2b discontinued treatment as a result of severe adverse effects. After 12 weeks of treatment, viral load reduction was>2 log(10) with both pegylated interferon-alpha-2a (-2.53) and pegylated interferon-alpha-2b (-2.48) with no significant difference. At the end of week 48, HCV RNA was undetectable in 14 of 54 patients (25.9%) receiving pegylated interferon-alpha-2a and in 15 of 54 patients (27.7%) receiving pegylated interferon-alpha-2b. When terminating follow-up, an SVR was observed in 11 of 54 patients (20.4%) who received pegylated interferon-alpha-2a and 10 of 54 patients (18.4%) receiving pegylated interferon-alpha-2b. The incidence and severity of adverse events was similar in both groups. CONCLUSIONS: Our results seem to show that in chronic hepatitis C patients who are non-responsive to previous therapy, EVR to the two pegylated interferons did not significantly differ with a similar therapeutic efficacy defined as SVR.

PMID: 18416586 [PubMed - in process]

[Marcia2202]

Very interesting. It practically says that they had more success with pegasys because ppl stopping tx on pegintron due to nontolerance. They were able to complete tx with pegasys instead. Is that correct?

Am not too good with all the medical language.

[mikesimon]

Aliment Pharmacol Ther. 2007 Dec 10 [Epub ahead of print]

Peginterferon alfa-2a/ribavirin in HCV patients nontolerant or nonresponsive to peginterferon alfa-2b/ribavirin.
Liver Transplantation Unit, Georgetown University Medical Center, Washington, DC, USA.

Background: Peginterferon alfa-2a/ribavirin had lower incidences of depression and flu-like symptoms than standard interferon/ribavirin, whereas peginterferon alfa-2b/ribavirin and standard interferon/ribavirin had similar incidences of these AEs. Aim: To assess the efficacy and safety of peginterferon alfa-2a/ribavirin in genotype 1-infected patients treated for up to 12 weeks with peginterferon alfa-2b/ribavirin but not achieving EVR (non-EVR) or non-tolerant (NT) due to depression, fatigue, flu-like symptoms, or injection-site reactions. Methods: NTs were treated for an additional 36 weeks and non-EVRs for an additional 60 weeks with peginterferon alfa-2a (180 mug/wk)/ribavirin (1000/1200 mg/d). Patients with detectable HCV-RNA after 12 weeks were discontinued. Results: Of 25 NTs, 23 (92%) were HCV-RNA negative after 12 weeks on peginterferon alfa-2a/ribavirin and 14 (56%) achieved SVR. Of 32 non-EVRs to peginterferon alfa-2b/ribavirin, 4 (12.5%) achieved EVR with peginterferon alfa-2a/ribavirin and 1 (3.1%) achieved SVR. Four non-EVRs and 0 NTs were withdrawn for AEs; 26 (81.2%) and 24 (96.0%), respectively, completed peginterferon alfa-2a/ribavirin treatment or were withdrawn for insufficient response at Week 12. In NTs, depression, fatigue, flu-like symptoms and injection-site reactions declined during treatment. Conclusion: Most patients who did not tolerate peginterferon alfa-2b/ribavirin due to AEs and who completed the full 36-week course of peginterferon alfa-2a/ribavirin treatment achieved SVR.

PMID: 18081737 [PubMed - as supplied by publisher]

[Marcia2202]

Thanks for your input. The link to where I found above mentioned info is www.talkaboutsupport.com/group/alt.support.hepatitis-c/messages/75803.html
The person who posted it does not state where she got it from.
Oops, I just realized its from 2005, probably totally outdated.... Sorry about that.

I have read a lot of things on our forum (dated 2007) where WBD Pegintron vs Pegasys is discussed. I weigh 56kg (123lb), so I would end up with a low dose of Pegintron (100mkg). It would probably be better for me to do Pegasys. The same with the Riba.

I think I have understood the reasoning behind that, but am still wondering if GT has to do with which one is more suitable.

I don't know my GT, yet. I was supposed to get the result this week, but due to teacher, nurses etc striking, I am still waiting.

I want to weigh out all my options, so I know what to discuss with the hepatologists, once we discuss tx.

Marcia

[mikesimon]

I'm not selling the stuff, I don't work for Roche or Schering-Plough and neither am I treating. I did treat with both drugs however. Feel free to post whatever you have. There isn't a lot out there. Mike

[Bigfloyd]

Interesting, but... SVR is what we after here and a single study is always suspect. Perhaps it was funded by Roche??? Perhaps Marcia would post a link that we could follow? The medical community does not seem conflicted on this topic.

[mikesimon]

I doubt those numbers are representative of the efficacy of the two interferons. From what I know the effectiveness of both are about the same though the side effects may be less severe with Pegasys.
Here is an article addressing 12 week response to both dugs. Admittedly it is not dealing with SVR numbers but I think we can rely on 12 weeks results as some  indication of the likelihood of achieving SVR.

J Viral Hepat. 2007 Oct;14(10):721-9
Di Bisceglie AM, Ghalib RH, Hamzeh FM, Rustgi VK.

Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St Louis, MO 63110, USA. ***@****

Patients infected with hepatitis C virus (HCV) genotype 1 and with serum HCV RNA concentrations over 800 000 IU/mL have relatively low rates of virologic response to pegylated interferons. The 2 forms of pegylated interferon have different pharmacokinetic profiles, and pilot studies comparing them have yielded varying results. We compared the virologic response to 12 weeks of treatment with peginterferon alpha-2a plus ribavirin vs peginterferon alpha-2b plus ribavirin in 380 patients who were infected with HCV genotype 1 and had high viral loads. We observed no between-group differences in viral load reduction over time and no differences in the percentage of patients treated with peginterferon alpha-2a or peginterferon alpha-2b plus ribavirin who achieved early virologic response (EVR), defined as >/=2-log reduction in HCV RNA concentration or undetectable HCV RNA at 12 weeks (66%vs 63%). Serum levels of interferon were more frequently below the level of quantitation in patients treated with peginterferon alpha-2b plus ribavirin (58-68%) than in those treated with peginterferon alpha-2a plus ribavirin (1-2%). Patients treated with peginterferon alpha-2b plus ribavirin had higher rates of discontinuation for safety reasons (6%vs 1%). In conclusion, a substantial percentage of patients infected with HCV genotype 1 and high viral load can achieve EVR when treated with peginterferon and ribavirin. The 2 pegylated interferons showed comparable anti-HCV activity during the first 12 weeks of treatment when combined with the same doses of ribavirin (1000-1200 mg/day), but discontinuations for safety reasons were higher in the patients treated with peginterferon alpha-2b plus ribavirin.

PMID: 17875007 [PubMed - indexed for MEDLINE]

Head to head studies with comparable ribavirin doses are hard to find. Generally the drugs seem to have very similar efficacy in the material I have seen.

Mike

[mirceani]

I did Pegintron in 2002, for about 8 weeks, dr stopped it saying it was not working.Side effects were quite bad.

Currently on week 30 pf Pegasys, cleared since week 8, side effects very mild.

So, for me, Pegasys works better. (gen 1b)

Mircea