Interferon

Originator

Fiblaferon,Bioferon,W. Germany,1983

Manufacturing Process

Semliki Forest arborvirus was grown in chick embryo tissue culture. The infectious tissue culture liquid was decanted and diluted with medium 199 to give a preparation containing between 106 and 106.5 mouse ID50 of virus/ml.
Calf kidneys, dog kidneys and rhesus monkey kidneys were treated with trypsin to give suspensions of cells. The suspensions were centrifuged and the packed cells diluted with 400 volumes (calf cells) or 200 volumes (dog cells and rhesus monkey cells) of a growth medium consisting of 5% horse serum and 0.5% lactalbumen hydrolysate in Earle's saline, with 100 units/ml each of penicillin and streptomycin. These media were used separately to produce Semliki Forest/calf interferon, Semliki Forest/dog interferon and Semliki Forest/rhesus monkey interferon. The cellcontaining growth medium was dispensed into 500 ml medical flat bottles (70 ml in each). The cultures were incubated at 36°C. Confluent sheets of cells (monolayers) were formed in 5 to 6 days. The growth medium was then removed and the monolayers were washed with isotonic phosphate-buffered saline, pH 7.5.
Each bottle for interferon production received the arborvirus preparation in medium 199 (0.5 ml) and further medium 199 (50 ml); some bottles received only medium 199 (50 ml) and no virus and served as controls. The bottles were incubated for 3 to 5 days at 36°C.
The supernatants containing the interferons were decanted from monolayers, pooled, and tested for freedom from bacteria. Residual arborvirus was inactivated by acid and heat as follows. The liquid was brought to pH 2 by the addition of 0.3N hydrochloric acid in Earle's saline (minus sodium chloride and sodium bicarbonate), kept at 4°C for 24 hours, and then brought back to pH 7by the addition of 0.3N sodium hydroxide in distilled water. The liquid was then heated at 56°C for 30 minutes.
At this stage the interferon preparations were assayed and submitted to safety tests for the absence of contaminating viruses.
Rhesus monkey kidney infected with Semliki Forest arborvirus gave interferon of titre 1.5 log interferon units/2 ml. (The interferon unit, determined in a volume of 2 ml, is the dilution of interferon which produced a half-maximal score for degree of cytopathic effect in virus-infected tissue culture tubes at the time when the control without interferon first showed the maximal score.)
Each interferon preparation was ultracentrifuged at 20,000 revolutions per minute for one hour to remove tissue debris and inactivated virus. The supernatant was dialyzed against distilled water (1:400) for 24 hours at 4°C. The material was then freeze-dried. Thedried product was reconstituted in one-tenth of the original volume in distilled water and dispensed into ampoules. Reconstituted solutions were assayed for interferon activity, examined for toxicity, and tested for sterility

Therapeutic Function

Antineoplastic, Antiviral

General Description

Interferon alfa-n3, Alferon N, is an α-interferon expressedfrom human leukocytes that are antigen-stimulated withavian Sendai virus.
Interferon alfa-n3 is indicated for intralesional treatment ofrefractory or recurrent condyloma acuminata (genital warts)in patients 18 years of age or older. These warts are associatedwith human papillomavirus (HPV). Interferon alfa-n3 is especiallyuseful in patients who have not responded well to othermodalities (podophyllin resin, surgery, laser, or cryotherapy).Interferon alfa-n3 is also being investigated for the treatmentof non-Hodgkin lymphoma, herpes simplex virus, rhinovirus,vaccinia, and varicella zoster. A usual dose in condylomaacuminata is 250,000 IU/wart, injected with a 30-gauge needlearound the base of the lesion.
Interferon alfa-n3 is contraindicated in persons sensitive tomouse immunoglobulin G (IgG), egg protein, and neomycin.Interferon alfa-n3 is supplied as a solution with the proteinin phosphate-buffered saline with phenol as a preservative.The solution should be stored at 2°C to 8°C withoutfreezing. Properly stored solution expires at 18 months.