Repeated episodes of fixed eruption 3 months after discontinuing pegylated interferon-alpha-2b plus ribavirin combination therapy in a patient with chronic hepatitis C virus infection

Pharmacists' role in multidisciplinary diagnosis and treatment in adverse reactions: A case report of interferon alfa-2b induced severe lupus

RATIONALE

Various side effects of interferon alfa-2b (IFN-α2b) have been reported. However, no relevant research has been conducted on the identification and treatment scheme selection for IFN-α2b induced severe systemic lupus erythematosus (SLE).

PATIENT CONCERNS

A 41-years-old man with a long history of hepatitis B who developed severe active SLE after IFN-α2b therapy for 24 months, with complete and persistent remission of clinical and laboratory abnormalities after IFN-α2b withdrawal, was not observed.

DIAGNOSIS

The patient was diagnosed with interferon-associated lupus by a multidisciplinary team involving pharmacists, and lupus nephritis by renal biopsy.

INTERVENTIONS

Methylprednisolone (40 mg/day) with intravenous cyclophosphamide (600 mg/body weight) was initiated and the symptoms were partially relieved. Cyclophosphamide was increased from 600 mg to 850 mg at the pharmacist's recommendation.

OUTCOMES

The patient showed a favorable response to these therapies.

LESSONS

Clinical pharmacists collaborated with other members of the health care team to diagnose and treat adverse reactions, resulting in improved patient management.

Development of latent Interferon alpha 2b as a safe therapeutic for treatment of Hepatitis C virus infection

Interferon therapy for the treatment of hepatitis C virus infection has very limited clinical application due to short serum half-life and side effects of therapy in systemic route of administration. In the present study, we have focused to improve the interferon therapy by overcoming the limitation of side effects. We hypothesized that latent interferon alpha 2b (IFNα2b) produced by fusion of Latency associated protein (LAP) domain of TGFβ and IFNα2b having HCV NS3 protease cleavage site as linker that will be activated only at target site (liver) by viral protease (HCV NS3 protease) present on the surface of infected cells. The fusion proteins were expressed in pichia pastoris as homodimer and cleaved by recombinant HCV NS3 protease in vitro into two fragments corresponding to the IFNα-2b and LAP respectively. The latency of chimeric proteins and biological activity after treatment with HCV NS3 protease was assessed by cytopathic effect inhibition assay in A594 cells infected with encephalomyocarditis virus (EMCV) and reduction in HCV viral load in Huh7 cells. The HCV NS3 protease was present on the surface of HCV replicating Huh7 cells in amount that activated half of the effective concentration (EC₅₀) of latent IFNα2b fusion protein. As free circulating HCV NS3 protease was not detected in sera from chronic HCV patients and in vitro cleavage of intact latent IFNα2b fusion protein was not observed with peripheral blood mononuclear cells (PBMCs) isolated from chronic HCV patients, thus there are less likely chances of activation and off target binding of latent IFNα2b to show side effects during systemic route of administration. Therefore, most of the side effects of interferon can be overwhelmed at the cost of 50% reduced biological activity. Thus, the use of latent IFNα2b can be considered again as an option for treatment of HCV infection in combination with direct acting antivirals rather than alone with improved safety profile.

Side effects of cytokines approved for therapy

Cytokines, currently known to be more than 130 in number, are small MW (<30 kDa) key signaling proteins that modulate cellular activities in immunity, infection, inflammation and malignancy. Key to understanding their function is recognition of their pleiotropism and often overlapping and functional redundancies. Classified here into 9 main families, most of the 20 approved cytokine preparations (18 different cytokines; 3 pegylated), all in recombinant human (rh) form, are grouped in the hematopoietic growth factor, interferon, platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ) families. In the hematopoietin family, approved cytokines are aldesleukin (rhIL-2), oprelvekin (rhIL-11), filgrastim and tbo-filgrastim (rhG-CSF), sargramostim (rhGM-CSF), metreleptin (rh-leptin) and the rh-erythropoietins, epoetin and darbepoietin alfa. Anakinra, a recombinant receptor antagonist for IL-1, is in the IL-1 family; recombinant interferons alfa-1, alfa-2, beta-1 and gamma-1 make up the interferon family; palifermin (rhKGF) and becaplermin (rhPDGF) are in the PDGF family; and rhBMP-2 and rhBMP-7 represent the TGFβ family. The main physicochemical features, FDA-approved indications, modes of action and side effects of these approved cytokines are presented. Underlying each adverse events profile is their pleiotropism, potency and capacity to release other cytokines producing cytokine 'cocktails'. Side effects, some serious, occur despite cytokines being endogenous proteins, and this therefore demands caution in attempts to introduce individual members into the clinic. This caution is reflected in the relatively small number of cytokines currently approved by regulatory agencies and by the fact that 14 of the FDA-approved preparations carry warnings, with 10 being black box warnings.