Lukey PT, et al. - In order to test safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD), researchers conducted a randomized, placebo-controlled, double-blind, repeat dose escalation, experimental medicine study of omipalisib in subjects with idiopathic pulmonary fibrosis (IPF). For approximately eight days, omipalisib was administered at 0.25 mg, 1 mg and 2 mg twice daily (BID) in 4 cohorts of 4 randomized 3:1 subjects to receive omipalisib or placebo (two cohorts received 2 mg BID). This experimental medicine study showed acceptable tolerability of omipalisib in IPF subjects at exposures for which the target engagement was systemically and in the lungs confirmed. Diarrhoea, reported by four participants, was the most common adverse event.