Company · CIK 1701108 # Spero Therapeutics, Inc. | CIK | [1701108](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=0001701108) (SEC EDGAR) | | --- | --- | | Industry (SIC) | 2834 — Pharmaceutical Preparations | | Incorporated in | DE | | Business address | MA | | Listed | SPRO (Nasdaq) | | First annual or quarterly report | 2017-12-14 | ## Offerings 6 registrations | Registration | Label and status | First filed | Last event | Filings | | --- | --- | --- | --- | --- | | 333-298641 | Shelf Effective | 2026-08-28 | 2026-09-10 | 2 | | 333-277998 | Shelf Effective | 2024-03-15 | 2024-03-22 | 2 | | 333-254170 | Shelf Effective | 2021-03-11 | 2021-03-29 | 2 | | 333-228661 | Shelf Effective | 2018-12-03 | 2020-11-13 | 7 | | 333-226093 | Registered company Final prospectus | 2018-07-09 | 2018-07-13 | 4 | | 333-220858 | IPO Final prospectus | 2017-10-06 | 2017-11-02 | 4 | ## Filings 23 | Filed | Filing | Registration | Accession | | --- | --- | --- | --- | | 2026-09-10 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999526002937/9999999995-26-002937-index.htm) Declared effective | 333-298641 | 9999999995-26-002937 | | 2026-08-28 | [S-3](https://www.sec.gov/Archives/edgar/data/1701108/000119312526374702/0001193125-26-374702-index.htm) Shelf registered | 333-298641 | 0001193125-26-374702 | | 2024-03-22 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999524000719/9999999995-24-000719-index.htm) Declared effective | 333-277998 | 9999999995-24-000719 | | 2024-03-15 | [S-3](https://www.sec.gov/Archives/edgar/data/1701108/000119312524069196/0001193125-24-069196-index.htm) Shelf registered | 333-277998 | 0001193125-24-069196 | | 2021-03-29 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999521001188/9999999995-21-001188-index.htm) Declared effective | 333-254170 | 9999999995-21-001188 | | 2021-03-11 | [S-3](https://www.sec.gov/Archives/edgar/data/1701108/000119312521077926/0001193125-21-077926-index.htm) Shelf registered | 333-254170 | 0001193125-21-077926 | | 2020-11-13 | [424B5](https://www.sec.gov/Archives/edgar/data/1701108/000119312520292384/0001193125-20-292384-index.htm) Shelf takedown | 333-228661 | 0001193125-20-292384 | | 2020-09-14 | [424B5](https://www.sec.gov/Archives/edgar/data/1701108/000119312520244773/0001193125-20-244773-index.htm) Shelf takedown | 333-228661 | 0001193125-20-244773 | | 2020-09-09 | [424B5](https://www.sec.gov/Archives/edgar/data/1701108/000119312520242277/0001193125-20-242277-index.htm) Shelf takedown | 333-228661 | 0001193125-20-242277 | | 2020-02-11 | [424B5](https://www.sec.gov/Archives/edgar/data/1701108/000119312520030568/0001193125-20-030568-index.htm) Shelf takedown | 333-228661 | 0001193125-20-030568 | | 2019-06-14 | [424B5](https://www.sec.gov/Archives/edgar/data/1701108/000119312519172777/0001193125-19-172777-index.htm) Shelf takedown | 333-228661 | 0001193125-19-172777 | | 2018-12-11 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999518003105/9999999995-18-003105-index.htm) Declared effective | 333-228661 | 9999999995-18-003105 | | 2018-12-03 | [S-3](https://www.sec.gov/Archives/edgar/data/1701108/000119312518341227/0001193125-18-341227-index.htm) Shelf registered | 333-228661 | 0001193125-18-341227 | | 2018-07-13 | [424B4](https://www.sec.gov/Archives/edgar/data/1701108/000119312518217909/0001193125-18-217909-index.htm) Final prospectus | 333-226093 | 0001193125-18-217909 | | 2018-07-12 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999518001785/9999999995-18-001785-index.htm) Declared effective | 333-226093 | 9999999995-18-001785 | | 2018-07-11 | [S-1/A](https://www.sec.gov/Archives/edgar/data/1701108/000119312518216210/0001193125-18-216210-index.htm) Amendment | 333-226093 | 0001193125-18-216210 | | 2018-07-09 | [S-1](https://www.sec.gov/Archives/edgar/data/1701108/000119312518214717/0001193125-18-214717-index.htm) Registration filed | 333-226093 | 0001193125-18-214717 | | 2018-05-25 | [DRS](https://www.sec.gov/Archives/edgar/data/1701108/000095012318005976/0000950123-18-005976-index.htm) Draft made public | 377-02085 | 0000950123-18-005976 | | 2017-11-02 | [424B4](https://www.sec.gov/Archives/edgar/data/1701108/000119312517331186/0001193125-17-331186-index.htm) Final prospectus | 333-220858 | 0001193125-17-331186 | | 2017-11-01 | [EFFECT](https://www.sec.gov/Archives/edgar/data/1701108/999999999517002842/9999999995-17-002842-index.htm) Declared effective | 333-220858 | 9999999995-17-002842 | | 2017-10-23 | [S-1/A](https://www.sec.gov/Archives/edgar/data/1701108/000119312517315961/0001193125-17-315961-index.htm) Amendment | 333-220858 | 0001193125-17-315961 | | 2017-10-06 | [S-1](https://www.sec.gov/Archives/edgar/data/1701108/000119312517305888/0001193125-17-305888-index.htm) Registration filed | 333-220858 | 0001193125-17-305888 | | 2017-08-25 | [DRS](https://www.sec.gov/Archives/edgar/data/1701108/000095012317008253/0000950123-17-008253-index.htm) Draft made public | 377-01690 | 0000950123-17-008253 | [All filings of this company](https://equitycapital.markets/filings?cik=1701108) · [CSV](https://equitycapital.markets/filings.csv?cik=1701108) --- Source page: https://equitycapital.markets/company/1701108 · Data: U.S. SEC EDGAR · CC BY 4.0