The purpose of this study is to examine the effects of multi-dose regimens of IPI-145 on lung function in mild asthmatic subjects following allergen challenge.

This is a phase 2a, randomized, double-blind, placebo-controlled, multi-dose, 2-way cross-over study designed to examine the effect of IPI-145 on lung function and inflammatory indices in mild, allergen-reactive asthmatic subjects undergoing allergen challenge.

Inclusion Criteria:

• Male or female adults between 18 and 60 years of age
• Diagnosis of asthma (mild) for at least 6 months prior to Screening
• Forced expiratory volume in one second (FEV1) ≥70% of predicted value at Screening
• A positive skin prick test to test allergen

Exclusion Criteria:

• Any prior treatment with a phosphoinositide-3-kinase (PI3K) inhibitor other than IPI-145 in a previous clinical study
• Acute asthma exacerbations within 6 weeks prior to Screening
• Use of any medication for the treatment of asthma other than a short-acting β2 agonist (as needed) within the 4 weeks prior to Screening
• Participation in another clinical study within minimum of 30 days prior to study Screening
• A positive screen result for active or latent tuberculosis
• A history of cardiovascular disease
• The concomitant use of acid-reducing agents and cholinesterase inhibiting medication
• Inadequate hepatic function defined by Aspartate Aminotransferase (AST) and/or Alanine Aminotransferase (ALT) greater than 1.5 times greater limit of normal (ULN)
• Inadequate renal function defined by serum creatinine greater than 2.0 milligrams/dL