Page 63 - The Flying Publisher Guide to Hepatitis C Treatment

Searching for new antiviral therapies | 63

alopecia compared to PegIFN. Development and testing of once
per month dosage is undergoing.

Controlled-release recombinant interferon alfa-2b
formulations were designed to improve the pharmacokinetic
parameters, in order to maintain continuous drug levels and
consequently minimize side effects as compared to current IFNs.
Locteron® (Biolex Therapeutics/OctoPlus) is a recombinant
nonglycosylate IFN alfa-2b produced in polyether-ester
microspheres. This steady controlled-release formulation avoids
fluctuation in IFN levels. A pilot study reported that after
injection of 320 µg Locteron®, the concentration of serum IFN
remained elevated through 14 days (De Leede 2008). Locteron®
can be administered twice monthly, with its trough
concentration between doses maintaining adequate antiviral
activity. Preliminary results of phase IIb studies, showed that in
treatment-naive patients, Locteron®, in combination with RBV,
produced similar viral suppression to that of PegIFN/RBV, with
fewer flu-like side effects and substantially lower rates of
depression.
IFN XL (Flamel Technologies) is an extra-long controlled-
release formulation of recombinant IFN alfa-2b, based on the
nanoparticles Medusa delivery system, designed for the
tailored delivery of fully-active proteins. Basically this is a
nanoparticle polymer with embedded IFN, which has a slow,
sustained release with increased efficacy. In a phase I study, IFN
XL induced greater reduction in VL after two weeks with fewer
AEs compared to PegIFN (Soriano 2009). A phase IIa study
designed to evaluate IFN XL in combination with RBV in naive
and previous G1 HCV non-responders to SoC is ongoing.
Omega interferon (Intarcia Therapeutics, Inc.) is a type 1
interferon delivered with an osmotic mini-pump implanted
subcutaneously. Omega DUROS® is a drug delivery system that
stabilizes therapeutic proteins, delivering a continuous dose of
omega interferon at a constant rate for 3 months.