Pegylation of interferon alfa-2b produces a product (PegIntron) whose clearance is lower than that of nonpegylated interferon alfa-2b. When compared to INTRON A, PegIntron (1 mcg/kg) has approximately a 7-fold lower mean apparent clearance and a 5-fold greater mean half-life, permitting a reduced dosing frequency. At effective therapeutic doses, PegIntron has approximately 10-fold greater Cmax and 50-fold greater AUC than interferon alfa-2b.
The treatment with most promising results is a combination of pegylated interferon alfa (Pegasys, PEG-Intron) and the antiviral drug, ribavirin. Interferon alfa is a protein which the human body produces naturally as a defense response to viral infections. Pegylation describes a chemical process that makes the interferon last longer in the body. Interferon increases the potency of ribavirin in the treatment of HCV.
The products in question are Temodar (temozolomide) for brain cancer and hepatitis C and cancer drugs PegIntron (pegylated interferon alfa-2b) and Intron A (interferon alfa-2b), according to Merck's just-published quarterly report. All three of the drugs were acquired when Merck bought Schering-Plough in 2009.
These results are similar to those seen with the 48-week treatment regimen of VICTRELIS added to peginterferon alfa-2b and ribavirin in HCV RESPOND-2, a pivotal Phase III study. Taken together, these studies showed that VICTRELIS combined with either peginterferon alfa-2a or alfa-2b and ribavirin achieved significantly higher SVR rates in chronic HCV genotype 1 patients who failed prior therapy compared to peginterferon and ribavirin alone.
These findings make a strong case for considering low-dose peginterferon alfa-2b as a maintenance therapy in patients with cirrhosis and portal hypertension who have failed hepatitis C eradication therapy," said principal investigator Nezam Afdhal, M.D., Chief of Hepatology at Beth Israel Deaconess Medical Center (BIDMC) and Associate Professor of Medicine at Harvard Medical School.
http://www.nature.com/eye/journal/v17/n4/full/6700391a.html
"INF-alpha therapy has been known to cause a variety of ocular lesions.1,2 Typical lesions include cottonwool spots and retinal haemorrhages at the posterior fundus, particularly around the optic disc, secondary to retinal ischaemia, which usually appear within 3 months of the onset of therapy.
Only one RCT of HBeAg-positive patients found a significant increase in HBsAg loss after interferon alfa-2b. Steroid pretreatment followed by interferon alfa-2b versus no antiviral drugs increased HBsAg loss at the end of treatments. Active treatments compared to each other did not demonstrate differences post-treatment HBsAg loss or combined outcomes that included loss HBsAg clearance.
ALT normalization was greater after adefovir versus placebo.
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.
Recommended
