This present invention relates to a method of treating a autoimmune, respiratory and/or inflammatory disease or condition (e.g., psoriasis, rheumatoid arthritis, asthma, COPD). The method comprises administering a PI3K Delta inhibitor or a dual PI3K Delta- Gamma inhibitor and a PDE4 inhibitor. The present invention also relates to pharmaceutical compositions containing a PI3K Delta or dual PI3K Delta-Gamma inhibitor and a PDE4 inhibitor.