Spero Therapeutics, Inc.

Listed Company

SPROCIK 0001701108NasdaqNon-AcceleratedSmaller ReportingPharmaceutical PreparationsDelawareFY ends Dec 31

Period

FY 2025

Revenue

$66.80M

Net Income

$8.60M

Total Assets

$68.92M

Equity

$59.02M

Shares Out

57.90M

Op. Cash Flow

$-12.62M

SPRO$1.58−36.29% · past yearDBEQ Basic

Daily closing prices

Business

Spero Therapeutics is a clinical-stage biopharmaceutical company focused on identifying and developing novel treatments for rare diseases and infections with high unmet medical need. The company's lead program, tebipenem HBr, is an oral carbapenem in development for complicated urinary tract infections; in September 2022, Spero licensed this program to GSK, which is advancing it through regulatory review with an FDA PDUFA date of June 18, 2026. Spero retains development and commercialization rights in Japan and certain Asian territories through its partner Meiji Seika Pharma. The company has discontinued development of earlier-stage programs SPR206 and SPR720.

Summary from 10-K filed 2026-03-26

Financials

Consolidated Statement of Income

Year Ended · In millions, except per-share amounts

Concept	FY 2025 2025-12-31	FY 2024 2024-12-31	FY 2023 2023-12-31	FY 2022 2022-12-31	FY 2021 2021-12-31
Grant revenue	7	21	7	5	15
Collaboration revenue - related party	47	27	96	46	—
Collaboration revenue	13	371,000	933,000	3	3
Total revenues	67	48	104	54	18
Research and development	38	97	51	48	65
General and administrative	21	24	26	36	42
Impairment of long-term asset	587,000	0	5	635,000	—
Restructuring	258,000	877,000	0	12	0
Total operating expenses	60	121	82	96	106
Income (loss) from operations	6	−73	21	−42	−88
Interest income	3	5	4	1	346,000
Other income (expense), net	7,000	60,000	−14,000	−55,000	−395,000
Total other income, net	3	5	4	−4	−2
Net income (loss) before income taxes	9	−69	25	−46	—
Income tax expense	−261,000	0	−3	0	—
Net income (loss) and comprehensive income (loss)	9	−69	23	−46	−90
Net income (loss) per share attributable to common stockholders, basic	0.15	−1.27	0.43	−1.23	−2.91
Net income (loss) per share attributable to common stockholders, diluted	0.15	−1.27	0.43	−1.23	−2.91
Weighted average common shares outstanding, basic:	56	54	53	38	31
Weighted average common shares outstanding, diluted:	59	54	53	38	31

Consolidated Balance Sheet

As of · In millions, except per-share amounts

Concept	FY 2025 2025-12-31	FY 2025 2025-09-30	FY 2024 2024-12-31	FY 2023 2023-12-31	FY 2022 2022-12-31
Cash and cash equivalents	40	—	53	76	109
Collaboration receivable, current - related party	25	—	49	49	0
Other receivables	28,000	—	3	2	1
Prepaid expenses and other current assets	2	—	2	4	3
Total current assets	67	—	107	131	114
Operating lease right-of-use assets	1	2	3	4	5
Other assets	153,000	—	153,000	435,000	6
Total assets	69	—	111	182	125
Accounts payable	693,000	—	7	1	617,000
Accrued expenses and other current liabilities	6	—	18	7	9
Operating lease liabilities	2	—	2	2	2
Income taxes payable	383,000	—	174,000	387,000	0
Deferred Revenue, Current	0	—	368,000	2	4
Deferred revenue, current - related party	258,000	—	22	25	6
Total current liabilities	9	—	49	37	22
Non-current operating lease liabilities	939,000	—	3	4	5
Deferred revenue, non-current	0	—	12	11	10
Deferred revenue, non-current - related party	0	—	576,000	24	12
Other long-term liabilities	91,000	—	0	87,000	96,000
Total liabilities	10	—	64	75	49
Commitments and contingencies (Note 11)	—	—	—	—	—
Preferred stock, $0.001 par value; 10,000,000 shares authorized, no shares issued and outstanding as of December 31, 2024 and 2023	0	—	0	0	0
Common stock, $0.001 par value; 120,000,000 shares authorized as of December 31, 2024 and 2023; 54,593,527 shares issued and outstanding as of December 31, 2024 and 52,999,680 shares issued and outstanding as of December 31, 2023	56,000	—	55,000	53,000	52,000
Additional paid-in capital	510	—	506	498	490
Accumulated deficit	−451	—	−460	−391	−414
Total stockholders' equity	59	—	46	107	76
Total liabilities and stockholders' equity	69	—	111	182	125

Consolidated Statement of Cash Flows

Year Ended · In millions, except per-share amounts

Concept	FY 2025 2025-12-31	FY 2024 2024-12-31	FY 2023 2023-12-31	FY 2022 2022-12-31	FY 2021 2021-12-31
Depreciation and amortization	0	2,000	367,000	869,000	646,000
Non-cash lease cost	1	1	969,000	678,000	471,000
Share-based compensation	4	8	8	9	9
Collaboration receivable, current and non-current - related party	24	46	−96	0	—
Other receivables	3	−2	−461,000	2	3
Prepaid expenses and other current assets	277,000	2	−799,000	5	−3
Other assets	0	282,000	−1,000	−3,000	−319,000
Accounts payable	−7	6	761,000	−484,000	−53,000
Accrued expenses and other current liabilities	−12	11	−2	−5	2
Deferred revenue	−13	−370,000	−933,000	22	11
Deferred revenue - related party	−22	−26	30	—	—
Other long-term liabilities	91,000	−87,000	−9,000	−42,000	−39,000
Operating lease liabilities	−1	−1	−1	−688,000	−503,000
Income taxes payable	209,000	−213,000	387,000	0	—
Net cash used in operating activities	−13	−23	−33	−8	−64
Net decrease in cash and cash equivalents	−13	−23	−33	−3	27

Filings

Filing historySign up free to browse every 10-K, 10-Q, 8-K, and proxy this filer has submitted to the SEC.Sign up free · Upgrade to Pro

Material Events

Material EventsTrack every 8-K filing and material event — AI-summarized, timelined, and alertable.Sign up free · Upgrade to Pro

Insiders

Insider ActivitySee executive buy/sell windows and insider trade activity over rolling 30/90/365-day windows.Sign up free · Upgrade to Pro

Institutional Holders

Institutional HoldersSee which funds hold this stock and track position changes quarter over quarter.Sign up free · Upgrade to Pro

Frequently asked questions

What is Spero Therapeutics, Inc.'s CIK number?

Spero Therapeutics, Inc.'s SEC CIK number is 0001701108 (1701108). The CIK (Central Index Key) is the permanent identifier the SEC assigns to every EDGAR filer — unlike a ticker symbol, it never changes.

Where can I find Spero Therapeutics, Inc.'s SEC filings?

All of Spero Therapeutics, Inc.'s EDGAR filings — 10-K annual reports, 10-Q quarterly reports, 8-K material events, and insider transactions — are listed on this page, sourced live from SEC EDGAR.

When did Spero Therapeutics, Inc. last report earnings?

Spero Therapeutics, Inc. (SPRO) most recently filed an earnings 8-K with the SEC on May 13, 2026, furnishing its results under Item 2.02 (Results of Operations and Financial Condition). The earnings press release is attached to that filing (accession 0001193125-26-221567). This is Spero Therapeutics, Inc.'s most recent earnings filing of record — not a forecast of its next earnings date.

What is Spero Therapeutics, Inc.'s most recent earnings 8-K?

Spero Therapeutics, Inc.'s latest earnings 8-K (Item 2.02) was filed May 13, 2026 under accession 0001193125-26-221567. It carries the quarterly or annual earnings press release — the earliest official, SEC-filed version of the results.

View Spero Therapeutics, Inc.'s latest earnings 8-K →
Look up any company's CIK number →