v3.25.4
Cover - USD ($)
 12 Months Ended
Dec. 31, 2025
Feb. 20, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-42504    
Registrant Name SIONNA THERAPEUTICS, INC.    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 84-2801521    
Entity Address, Address Line One 21 Hickory Drive,    
Entity Address, Address Line Two Suite 500,    
Entity Address, City or Town Waltham,    
Entity Address, State or Province MA    
Entity Address, Postal Zip Code 02451    
City Area Code 617    
Local Phone Number 819-2020    
Title of 12(b) Security Common Stock, $0.001 par value per share    
Trading Symbol SION    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company true    
Entity Ex Transition Period false    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction false    
Entity Shell Company false    
Entity Public Float     $ 342,014,009
Entity Common Stock, Shares Outstanding   44,998,073  
Documents Incorporated by Reference
The registrant intends to file a definitive proxy statement pursuant to Regulation 14A relating to the 2026 Annual Meeting of Stockholders within 120 days of the end of the registrant’s fiscal year ended December 31, 2025. Portions of such definitive proxy statement are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein.
    
Central Index Key 0002036042    
Amendment Flag false    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2025