Annual report pursuant to Section 13 and 15(d)

Document And Entity Information

Document And Entity Information - USD ($)
12 Months Ended
Mar. 31, 2022
Jul. 29, 2022
Sep. 30, 2021
Cover [Abstract]      
Entity Registrant Name ACASTI PHARMA INC.    
Entity Incorporation, State or Country Code Z4    
Entity Tax Identification Number 98-1359336    
Entity Central Index Key 0001444192    
Current Fiscal Year End Date --03-31    
Entity File Number 001-35776    
Entity Address, Address Line One 3009 boul. de la Concorde East, Suite 102    
Entity Address, City or Town Laval    
Entity Address, State or Province QC    
Entity Address, Country CA    
Entity Address, Postal Zip Code H7E 2B5‌    
City Area Code 450    
Local Phone Number 687-2262    
Entity Filer Category Non-accelerated Filer    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Emerging Growth Company false    
Entity Small Business true    
Entity Interactive Data Current Yes    
ICFR Auditor Attestation Flag false    
Entity Common Stock, Shares Outstanding (in shares)   44,494,193  
Entity Public Float     $ 25,942,990
Entity Shell Company false    
Document Type 10-K/A    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Mar. 31, 2022    
Document Fiscal Year Focus 2022    
Document Fiscal Period Focus FY    
Amendment Flag true    
Title of 12(b) Security Common Shares, no par value per share    
Security Exchange Name NASDAQ    
No Trading Symbol Flag true    
Auditor Firm ID 85    
Auditor Location KPMG LLP    
Auditor Name Montréal, QC, Canada    
Amendment Description Acasti Pharma Inc. (the “Company”, “we”, “our” and “us”) is filing this Amendment No. 1 to Annual Report on Form 10-K (this “Amendment No. 1”) to amend its Annual Report on Form 10-K for the fiscal year ended March 31, 2022, as originally filed with the U.S. Securities and Exchange Commission, or the SEC, on June 21, 2022 (the “Original Form 10-K”), to include the information required by Items 10 through 14 of Part III of Form 10-K (the “Part III Information”). The Part III Information was previously omitted from the Original Form 10-K in reliance on General Instruction G(3) to Form 10-K, which provides that in the event our definitive proxy statement is not filed with the SEC within 120 days after the end of the fiscal year covered by the Original Form 10-K, the information in Part III may be incorporated by reference from an amendment to the Original Form 10-K filed no later than 120 days after the end of the fiscal year covered by the Original Form 10-K. Because we do not anticipate that our definitive proxy statement will be filed within 120 days after the fiscal year covered by the Original Form 10-K, we are filing this Amendment to include the Part III Information. This Amendment hereby amends the cover page, Part III, Items 10 through 14, and Part IV, Item 15 of the Original Form 10-K. In addition, as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended, or the Exchange Act, new certifications by our principal executive officer and principal financial officer are filed as exhibits to this Amendment. This Amendment does not amend or otherwise update any other information in the Original Form 10-K. Accordingly, this Amendment should be read in conjunction with the Original Form 10-K and with our subsequent filings with the SEC.