Stabilized interferon liquid formulations

Stabilized liquid pharmaceutical composition comprising an interferon (IFN) or an isoform, mutein, fused protein, functional derivative, active fraction or salt thereof, wherein said formulation is a solution that comprises a buffer, a cyclodextrin, an isotonicity agent and an anti-oxidant are described here. Preferably the interferon is interferon beta-1a and the cyclodextrin is HPBCD. These formulations are stable at room temperature, thus bringing the advantage of lower costs for formulation storage and increased safety for the patient with respect to possible "errors" during handling. As a matter of fact, having such formulations stable at room temperature reduces the risk of formation of degradation products potentially responsible for adverse events (e.g. immunogenicity).