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LS Mean Relative Change FEV1 (% ± SE) ARIKACE Phase 3 Trial Primary Endpoint: Relative Change in FEV1 ANCOVA Model Day 168: 95% CI for mean difference from ANCOVA ( -4.95, 2.34) Study Days Mean (SE) 128/135 128/134 127/134 127/135 125/135 127/132 127/135 126/132 TOBI® P-value 0.4809 Arikace

LS Mean Change Sputum P. aeruginosa (log10 CFU ± SE) ANCOVA Model Day 168: 95% CI for mean difference from ANCOVA ( -0.878, 0.106) ARIKACE Phase 3 Trial Secondary Endpoint: Change in P. aeruginosa Sputum Density Study Days Mean (SE) 120/124 115/118 116/114 111/118 114/120 116/117 117/119 119/115 Arikace TOBI® P-value 0.1239 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 14 28 57 84 113 140 168

 Overview of Adverse Events Arikace® QD (N=148) TOBI® BID (N=146) Overall (N=294) Number (%) of subjects with treatment-emergent adverse events 125 ( 84.5) 115 ( 78.8) 240 ( 81.6) Number of treatment-emergent adverse events 614 435 1049 Number (%) of subjects with treatment-emergent adverse events by maximum severity Grade 1: Mild 52 ( 35.1) 50 ( 34.2) 102 ( 34.7) Grade 2: Moderate 62 ( 41.9) 59 ( 40.4) 121 ( 41.2) Grade 3: Severe 11 ( 7.4) 5 ( 3.4) 16 ( 5.4) Grade 4: Life Threatening or Disabling 0 ( 0.0) 1 ( 0.7) 1 ( 0.3) Grade 5: Death 0 ( 0.0) 0 ( 0.0) 0 ( 0.0) Number (%) of subjects with treatment-emergent adverse events by seriousness Serious 26 ( 17.6) 29 ( 19.9) 55 ( 18.7) Not Serious 125 ( 84.5) 113 ( 77.4) 238 ( 81.0) Number of treatment-emergent serious adverse events 35 38 73 Number (%) of subjects with treatment-emergent serious adverse events by strongest relationship to study drug [1] Related 1 ( 0.7) 1 ( 0.7) 2 ( 0.7) Not Related 25 ( 16.9) 28 ( 19.2) 53 ( 18.0) Note: Adverse events were collected starting with the administration of the first dose of study drug Day 1. All reported AEs were coded using MedDRA 15.0. As applicable, if an adverse event was reported more than once during the study period for a given subject, the greatest severity and the worst-case relationship is presented. Missing severity, relationship or outcome are classed as unknown. [1] Related refers to those events that are possibly or probably related to study drug or study procedure (separately) or with an unknown relationship; unrelated refers to those events that are unlikely related to study drug or study procedure or collected as not related.

Summary ARIKACE met the primary endpoint If approved, once a day ARIKACE comparable to twice a day TOBI® (current standard of care) A new antibiotic formulation with evidence of antimicrobial activity No unexpected adverse events and no difference in serious adverse events vs. TOBI* >75% of patients carried over into the 2 year extension study** *26 Serious adverse events (SAE’s) in ARIKACE arm vs. 29 SAEs in TOBI arm; overall 614 adverse events in ARIKACE arm vs. 435 in TOBI arm **% of patients who had at least one dose of drug in study