Efficacy and safety of interferon-gamma in chronic granulomatous disease: a systematic review and meta-analysis
Authors: Reyes Saul Oswaldo Lugo , Garay Alejandro Gabriel González , Bobadilla Norma Yvett González , Lizárraga Diana Alejandra Rivera , Paz Araceli Catalina Madrigal , Medina-Torres Edgar Alejandro , Cardona Aristóteles Alvarez , Ortega José Luis Galindo , Galicia Cecilia Solís , Espinosa-Padilla Sara Elva , Murata Chiharu 
Published: September 2022

BACKGROUND: Chronic granulomatous disease (CGD) is a primary immunodeficiency with increased susceptibility to several bacteria, fungi, and mycobacteria, caused by defective or null superoxide production by the NADPH oxidase enzymatic complex. Accepted treatment consists mainly of antimicrobial prophylaxis. The role of human recombinant subcutaneous interferon gamma (IFNγ) is less clear, as available clinical evidence on its safety and efficacy is scarce and conflicting.
OBJECTIVE: We aimed to assess the efficacy and safety of IFNγ as an added treatment for CGD when compared to antimicrobial prophylaxis alone.
METHODS: A literature search was conducted using MeSH terms “Chronic granulomatous disease” AND (“interferon gamma” OR “interferon-gamma”), as well as antibiotics, placebo, no therapy, clinical trial, trial; on MEDLINE, EMBASE, LILACS, WHOs, CENTRAL, KOREAMED, The Cochrane Library, clinicaltrials.gov, and abstracts from meetings, from 1976 to July 2022. We included clinical trials (CT) and prospective follow-up studies and registered the number of serious infections (requiring hospitalization and IV antibiotics) and deaths; adverse events, and autoimmune complications, in patients treated for CGD with antimicrobial prophylaxis plus IFN-γ, versus antimicrobial prophylaxis alone. We assessed the quality of the studies using Risk of Bias and STROBE. We performed a meta-analysis by calculating both Peto odds ratio (OR), and Risk Reduction (RR) through the Mantel-Haenzsel method with a fixed effect model, using Review Manager 5.4, and we reported the number needed to treat (NNT).
RESULTS: We identified 54 matches from databases, and 4 from other sources. We excluded 12 duplicates, 7 titles, and 9 abstracts for relevance, after which we had 30 eligible studies. Twenty-four were then excluded after reading the full text. Six papers were included: one randomized CT, and 5 follow-up studies. In total, 324 patients with Chronic granulomatous disease were followed for 319 months under treatment with antibiotic prophylaxis plus interferon-gamma or placebo (or antibiotic prophylaxis alone), reported between the years 1991 and 2016. Three of the studies included a control group, allowing for the aggregate analysis of efficacy (prevention of serious infections). The aggregate OR was 0.49, with a 95% confidence interval of 0.19 to 1.23. The Risk Ratio for serious infection was 0.56 (95%CI 0.35-0.90) under IFNG. The meta-analysis thus favors interferon-gamma for a risk reduction of serious infection.
DISCUSSION: The results from this meta-analysis support the use of IFNg in the treatment of patients with CGD. However, we found insufficient clinical evidence and believe more clinical trials are needed to better assess the efficacy and long-term safety of IFNγ.