Combination therapy with pegylated interferon alpha-2b and adefovir dipivoxil in HBeAg-positive chronic hepatitis B versus interferon alone: a prospective, randomized study.

Currently available monotherapies of oral nucleoside/nucleotide analogs or interferon are unable to achieve a sustained and effective response in most of patients with chronic hepatitis B (CHB). The objective of the present study was to compare the efficacy and safety of pegylated interferon (Peg-IFN) alpha-2b plus adefovir dipivoxil combination therapy versus Peg-IFN alpha-2b alone. Sixty-one HBeAg-positive chronic hepatitis B patients were randomized to receive Peg-IFN alpha-2b alone (1.5 µg/kg once weekly) or Peg-IFN alpha-2b plus adefovir (10 mg daily) for up to 52 weeks. Efficacy and safety analyses were performed on all participants who received at least one dose of study medication. The rate of HBeAg seroconversion and undetectable HBV-DNA were evaluated after 52 weeks of therapy. At the end of treatment, 11 of 30 (36.7%) patients receiving combination therapy achieved HBeAg seroconversion versus 8 of 31 (25.8%) in the monotherapy group (P=0.36). In contrast, the percentage of patients with undetectable serum HBV DNA was significantly higher in the combination group than in the monotherapy group (76.7% vs. 29.0%, P<0.001). Thyroid dysfunction was more frequent in the combination group than in the monotherapy group (P<0.05). In HBeAg-positive CHB, combination of Peg-IFN alpha-2b and adefovir for 52 weeks resulted, at the end of treatment, in a higher virological response but without significant impact on the rate of HBeAg seroconversion and possibly an adverse effect on thyroid function.

Different EDC/NHS activation mechanisms between PAA and PMAA brushes and the following amidation reactions.

Infrared spectroscopy was applied to investigate the well-known EDC/NHS (N-ethyl-N'-(3-(dimethylamino)propyl)carbodiimide/N-hydroxysuccinimide) activation details of poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMAA) brushes grafted on porous silicon. Succinimidyl ester (NHS-ester) is generally believed to be the dominant intermediate product, conveniently used to immobilize biomolecules containing free primary amino groups via amide linkage. To our surprise, the infrared spectral details revealed that the EDC/NHS activation of PMAA generated anhydride (estimated at around 76% yield and 70% composition), but not NHS-ester (around 5% yield and 11% composition) under the well-documented reaction conditions, as the predominant intermediate product. In contrast, EDC/NHS activation of PAA still follows the general rule, i.e., the expected NHS-ester is the dominant intermediate product (around 45% yield and 57% composition), anhydride the side product (40% yield and 28% composition), under the optimum reaction conditions. The following amidation on PAA-based NHS-esters with a model amine-containing compound, L-leucine methyl ester, generated approximately 70% amides and 30% carboxylates. In contrast, amidation of PAA- or PMAA-based anhydrides with L-leucine methyl ester only produced less than 30% amides but more than 70% carboxylates. The above reaction yields and percentage compositions were estimated by fitting the carbonyl stretching region with 5 possible species, NHS-ester, anhydride, N-acylurea, unreacted acid, unhydrolyzed tert-butyl ester, and using the Beer-Lambert law. The different surface chemistry mechanisms will bring significant effects on the performance of surface chemistry-derived devices such as biochips, biosensors, and biomaterials.