An immune response mediated by type 2 cytokines is thought to contribute to the development and unfavorable outcome of aspergillosis. Adjuvant therapy with interferon-γ (IFN-γ) and granulocyte-macrophage colony stimulating factor (GM-CSF) was added to antifungal treatment in three nonneutropenic patients (one HIV-positive and two HIV-negative patients) with culture proven aspergillosis refractory to classical antifungal therapy. Clinical improvement was observed concomitantly with an increase in peripheral blood leukocyte proliferation and type 1 cytokines production. Our findings suggest an association between the improvement in type 1 cytokine production observed during IFN-γ and GM-CSF administration and a better control of Aspergillus infection in patients with progressive disease despite adequate antifungal therapy.