Immune-based therapy using gamma interferon ingaron in the treatment of HIV/AIDS patients with active pulmonary tuberculosis (PTB) not previously highly active antiretroviral therapy (HAART)

Abstract

Background: Interferon gamma is a licensed product for treating certain immune deficiency diseases, but its use in people with HIV is experimental. IFN- gamma is normally made by CD4 T-cells - the cells which are depleted in people with AIDS. It has antineoplastic and antiviral activity mediated by immunomodulatory effects. It is therefore theorized that giving HIV-positive people co-infected with TB supplementary injections of IFN- gamma may help boost their immune response. Objective: To obtain preliminary information on the safety, immunologic and virologic effects of IFN- gamma in adults co-infected with HIV and TB with immune reserve (CD4T-cells >350 cells/ml) on TB medication alone. Materials and methods: 21 HIV-infected adults newly diagnosed with active PTB with a median CD4 cells >350 cells/ml not previously on HAART, apart from standard TB medication also received IFN- gamma injection (Ingaron) at a dose of 500 000 i.u. subcutaneously three times weekly for eight weeks, while the control group (30) received similar TB treatment plus placebo. They were assessed clinically weekly, while laboratory investigations were conducted at the initiation of therapy and at weeks 4 and 8. Results: Outcome of TB treatment at 8 weeks of follow up showed a remarkable improvement of clinical conditions and immunologic responses of the patients on IFN- gamma (Ingaron) as against those in the control group. In general, gamma -IFN therapy was well tolerated. CD4+ increased from 656.2 +/- 41.3 to 728.4 +/- 74.7 cells/ml (p>0.05) while plasma RNA became undetectable in 11 patients in the study group as against nil in the control group. Conclusion: IFN- therapy in patients co-infected with HIV and tuberculosis receiving TB medication is safe, improves clinical outcome and enhances host defense mechanism. Larger studies will be needed to assess the drug�s long term clinical efficacy in the treatment of HIV-associated complications such as PTB.