Company: SION
Filing Date: 2025-01-17
Form Type: S-1
Source: 0001193125-25-008474
Chunk: 181

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-01-17
Form: S-1
Chunk 181
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 moderate in severity. Two serious adverse events (“SAEs”) occurred in two subjects receiving galicaftor in combination with navocaftor (ileus and cholecystitis acute); both were considered unrelated to the trial drugs by the investigator. |

| • |     | Trial GLPG-2222-CL-202 was a Phase 2 dose-ranging trial conducted by Galapagos in Europe and the U.S. to evaluate the                                                                                                                      
 safety and tolerability and the effect on CFTR function (as assessed by sweat chloride), pulmonary function and the Cystic Fibrosis Questionnaire—Revised (“CFQ-R”), which measures health-related quality of life, of galicaftor in 59 CF 
 patients that were homozygous for F508del mutation. The trial was completed in October 2017.                                                                                                                                               |

| • |     | Four doses of galicaftor were tested in this trial (50 mg, 100 mg, 200 mg, 400 mg QD) over 29 days. |

| • |     | Galicaftor was generally well-tolerated in this trial. The majority of reported treatment-emergent AEs were mild or                                                                                                                                       
 moderate in severity. A total of four SAEs were reported (two after galicaftor, two after placebo) in two subjects in the pooled placebo and one subject in the galicaftor 100 mg QD treatment group, respectively. The three subjects experienced one or 
 two events of infective pulmonary exacerbation of CF, all of which were considered not related to trial drug.                                                                                                                                             |

| • |     | Sweat chloride levels, lung function (ppFEV1) and CFQ-R were also                                                                                                                                                                                       
 assessed as secondary endpoints. Mean sweat chloride concentrations decreased dose-dependently with increasing doses of galicaftor, with a maximum decrease observed in the 200 mg QD treatment group on days 15 and 29, with statistically significant 
 LS means differences compared to placebo of -11.2 (95% CI, -19.1; -3.3; p=0.0062) and -15.8 (95% CI, -23.2; -8.3; p<0.0001) mmol/L, respectively. After termination of the trial drug, mean sweat chloride concentrations returned to baseline values   
 in all treatment groups. Percent predicted FEV1 and CFQ-R did not significantly improve in any