Correlation Between Circulating Galactomannan and Beta-D-glucan and Clinical Outcome of Invasive Aspergillosis

A major challenge in the development of antifungal therapies for invasive fungal infections is the difficulty in assessing early treatment response and clinical prognosis. Mycological endpoints are often unreliable, reflected by the low sensitivity of fungal cultures to diagnose infection (20% for aspergillosis). Radiographic endpoints can be misleading, particularly when assessed early following treatment initiation. Clinical endpoints can be ambiguous indicators of treatment response, and generally include categorization of patient outcome as better, stable or worse. Furthermore, clinical assessments are likely confounded by the underlying diseases predisposing to fungal infection. Thus, a biomarker interposed between the initiation of antifungal therapy and patient outcome would bring much needed precision in the evaluation of novel antifungal drugs and thus serve as a valuable tool to guide decision-taking regarding ineffective treatments and dose selection in product development. The current absence of such biomarkers represents a critical capability gap. To date, only few studies have examined the prognostic value of fungal biomarkers in invasive aspergillosis on clinical outcome and have been limited by sample seize. To address this issue, the current study will examine the correlation between the fungal biomarkers galactomannan and beta-D-glucan with clinical outcome in invasive aspergillosis. The study will also incorporate C-reactive protein (CRP) levels, as they seem to be a useful surrogate marker of IL-6 production.

The investigator contains a sample database of 100+ patients with either probable or proven invasive aspergillosis for which daily marker levels and CRP (during the first two weeks of antifungal therapy) were measured and clinical assessment data at (2, 4 and ) 6 weeks post-treatment.

The study will evaluate whether serial serum measurements of galactomannan/beta-D-glucan during the first week(s) of antifungal therapy can distinguish between successful clinical outcome and failed clinical outcome at 6 weeks in patients with proven and probable invasive aspergillosis.

The study aims also at exploring various cut points for galactomannan/beta-D-glucan measurements at two weeks after initiation of antifungal therapy and at exploring the sensitivity and specificity for predicting clinical outcome at 6 and 12 weeks in patients with proven and probable invasive aspergillosis.