快樂小藥師 Im pharmacist nichts glücklich

最近剛好有醫師問到interferon alfacon-1，所以我簡單找了一些他的介紹如下：

DESCRIPTION

Interferon alfacon-1 is a recombinant non-naturally occurring type-I interferon.

The 166-amino acid sequence of Interferon alfacon-1 was derived by scanning

the sequences of several natural interferon alpha subtypes and assigning

the most frequently observed amino acid in each corresponding position.1

Four additional amino acid changes were made to facilitate the molecular

construction, and a corresponding synthetic DNA sequence was constructed

using chemical synthesis methodology. Interferon alfacon-1 differs from

interferon alfa-2b at 20/166 amino acids (88% homology), and comparison with

interferon-beta shows identity at over 30% of the amino acid positions. Interferon

alfacon-1 is produced in Escherichia coli (E. coli) cells that have been genetically

altered by insertion of a synthetically constructed sequence that codes for

Interferon alfacon-1. Prior to final purification, Interferon alfacon-1 is allowed to

oxidize to its native state, and its final purity is achieved by sequential passage

over a series of chromatography columns. This protein has a molecular weight

of 19,434 daltons.

INFERGEN is a sterile, clear, colorless, preservative-free liquid formulated with

100 mM sodium chloride and 27 mM sodium phosphate at pH 7.0 ± 0.2. The

product is available in single-use vials containing 9 mcg and 15 mcg Interferon

alfacon-1 at a fill volume of 0.3 mL and 0.5 mL, respectively. INFERGEN vials

contain 0.03 mg/mL Interferon alfacon-1, 5.9 mg/mL sodium chloride, and

3.8 mg/mL sodium phosphate in Water for Injection, USP. INFERGEN is to be

administered undiluted by subcutaneous (SC) injection.

CLINICAL PHARMACOLOGY

General

Interferons are a family of naturally occurring, small protein molecules with

molecular weights of 15,000 to 21,000 daltons that are produced and secreted

by cells in response to viral infections or to various synthetic and biological

inducers. Two major classes of interferons have been identified (i.e., type-I and

type-II). Type-I interferons include a family of more than 25 alpha interferons

as well as beta interferon and omega interferon. While all alpha interferons

have similar biological effects, not all the activities are shared by each alpha

interferon and, in many cases, the extent of activity varies substantially for each

interferon subtype.

All type-I interferons share common biological activities generated by binding of

interferon to the cell-surface receptor, leading to the production of several

interferon-stimulated gene products. Type-I interferons induce pleiotropic biologic

responses which include antiviral, antiproliferative, and immunomodulatory

effects, regulation of cell surface major histocompatibility antigen (HLA class I

and class II) expression and regulation of cytokine expression. Examples

of interferon-stimulated gene products include 2´5´ oligoadenylate synthetase

(2´5´ OAS) and [1]-2 microglobulin.

The antiviral, antiproliferative, natural killer (NK) cell activation, and gene-induction

activities of INFERGEN have been compared with other recombinant alpha

interferons in in vitro assays and have demonstrated similar ranges of activity.

INFERGEN exhibited at least 5 times higher specific activity in vitro than

Interferon alfa-2a and Interferon alfa-2b.2 Comparison of INFERGEN with a

WHO international potency standard for recombinant alpha interferon (83/514)

revealed that the specific activity of INFERGEN in both an in vitro antiviral cytopathic

effect assay and an antiproliferative assay was 1 x 109 U/mg. However,

correlation between in vitro activity and clinical activity of any interferon is

unknown.