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Spero Therapeutics Inc (SPRO)
NASDAQHealth CareBiotechnologySnapshot 2026-06-15
Intact
$2.91+2.11%
Close 2026-06-15 · 1-day change
Recent financial performance is holding in the top half of its industry — the reason to own it looks intact.
The bottom line
Recent financial performance is strong, but earnings quality is fragile, reported profits aren't backed by cash. Management's recent track record has been steady, while risk is elevated and the sector backdrop is a headwind. Peer multiples imply a price about 33% above where it trades (it looks cheap on this basis); the read is cheap, value-trap risk, as it trades below peer multiples, but recent financials are weak or earnings quality is fragile. If SPRO cuts guidance on the next call, that could be a meaningful negative. This read is provisional.
as of 2026-06-15
Quick facts
- Exchange
- NASDAQ
- Sector
- Health Care
- Industry
- Biotechnology
- Market cap
- $165.02M
- Employees
- —
- IPO date
- 2017-10-06
- Next earnings
- —
Price
Daily closes. Earnings/event dots are placed inline.
Adjusted daily closes (split & dividend). Scroll over the chart to zoom; click a range to reset.
EarningsMaterial event
What's priced in
(what the market already expects)What it's worth (estimated)
A consensus fair price across 4 valuation methods, at three horizons. Current price $2.91. Estimates are diagnostics, not price targets. Short-horizon estimates are close to coin-flips, so confidence is a method-agreement read, not a prediction.
12-month· primaryinexpensive
$4.32consensus
Range $3.72 – $6.01
vs price: -33% below
Method agreement — · 4 methods
No-growth: today's peer multiple on trailing earnings. The headline read.
3-yearinexpensive
$7.36consensus
Range $4.91 – $9.82
vs price: -60% below
Method agreement — · 2 methods
Embeds projected growth. Leans optimistic by design. Upside context.
5-yearinexpensive
How much to trust our fair value
We take the 12-month fair value above and grade our own number — how the market prices this name versus what we'd justify, and where the two diverge.
Cheap vs peershigh confidence
At $2.91 SPRO trades at 12× p/e, below its 17× p/e peer median. Our $4.32 fair value sits above the price; high confidence. Not investment advice.
Multiple (P/E)
11.9x
peer 16.8x · own history —
Premium
0.7x peer
Growth the price needs
-33%
our forecast 53%
Our fair value
$4.32
range $3.72 – $5.96
How this stock is priced
One valuation read at a 12-month horizon, plus how price compares to peers and the company's own history.
Long-term · 1–3 yr
inexpensivecheap — value-trap risk12-month view
What's priced inJustified
The price implies about 33% below a flat-multiple fair value, below our forecast of about 53%. This describes what's priced in, not a forecast of the move.
Low fragilityrisk posture, not a price call
Only weak execution quality, a turbulent sector regime (Heating) — not the full expensive x weak x turbulent stack.
Historical context
For similar setups historically (n=20,154): about 33% saw a 20%+ drawdown, and roughly 76% of those did not recover within the year. These are historical base rates for the cohort, not a forecast of this stock.
How strong is the business
(quality & execution)Factor signals
Each factor is a parallel diagnostic with a clear read of what it shows and how names like it have historically fared. Never aggregated into a single score.
Recent financial performance
strongOperating income rose in 1 of the last 3 quarter-over-quarter moves. Historically, Health Care names rated strong grew net income 59% of the time over the next year (vs 52% for the rest of the cohort, n=2344).
78th pctl · Health Care
Earnings quality
fragileOver the trailing year it converted 0.48x of net income into operating cash flow. Historically, Health Care names rated fragile grew net income 40% of the time over the next year (vs 56% for the rest of the cohort, n=1703).
22nd pctl · Health Care
Macro sensitivity
Not enough signal yet.
Not enough signal to read sensitivity to the US dollar, the broad stock market, Fed net liquidity, real (inflation-adjusted) rates, long-term interest rates.
Management & capital allocation
stableEarnings setup & market context
The next print and the backdrop around it (sector regime and the AI cycle). Context for the path, not a forecast of returns.
Earnings setup · pre-print positioning
forward-looking
for period ending 2026-06-30
Why this setup
Rating actions
0 upgrades, 0 downgrades / 30d. 0% of analysts rate Buy.
Sector context
Intermediate · WeeklySector phase: health care is in maturing, with decelerating (~0.5 years in phase).
Sector regime (90d momentum): headwind.Secular epoch: Mature by revenue growth · theme biologics/biosimilars.headwind-9.9%sector vs S&P 500, 60d
via XLV
Tailwind = sector leading the S&P 500; headwind = trailing. Both can be constructive. Historically, headwind regimes have averaged stronger forward returns than tailwind.
Management scorecard
How management runs the business: capital, margins, balance sheet, and how reliably they guide and deliver.
Long-term · 1–3 yr
Overall: neutral
- Capital allocation
- neutral
- Earnings discipline
- neutral
- Margin discipline
- neutral
- Balance sheet
- neutral
- Post-call reaction
- weak
A guidance track record builds as the company issues and delivers on guidance.
as of 2026-06-15
How bumpy is the path
(risk while you hold it)Risk: how this stock moves
What a normal day, a bad day, and the worst of the last year would mean for a $10,000 position.
Intermediate · WeeklyLong-term · 1–3 yr
On a typical day, $10k can swing ±$186.
How much price usually moves either way.
On a bad day, this stock has moved -$554.
A rough but not unusual down day (about the 95th percentile).
In the worst 12 months, $10k could have lost $3,980.
Deepest peak-to-trough drop in the last year.
elevatedas of 2026-06-15
Past results, not a forecast. Not investment advice.
What would change the read
(catalysts & re-read triggers)What changed
The most important moves since the prior daily snapshot.
Short-term · Daily
- No material changes since the prior snapshot.
No material changes since the prior snapshot.
as of 2026-06-15
What to watch next
Specific, dated things to watch for, each with what would confirm it and what would prove it wrong.
Intermediate · Weekly
- UpsideMedium confidenceQuartersactive 4d
Watch for sector revenue growth speeding up.
Why it matters: If healthcare sector revenue growth speeds up, it may benefit Spero's performance.
What confirms / what disproves
Confirms:Healthcare sector revenue growth exceeds 10% year over year.
Disproves:Healthcare sector revenue growth remains below 10% year over year.
Sector context
as of 2026-06-15
News catalysts
Recent news graded against this company's own objectives — whether it reinforces or challenges the thesis, and how confirmed it is.
No graded news catalysts for SPRO yet.
This sector is also watching
- Watch for revenue growth re-acceleration in Health Care
What could change this view
Conditional scenarios: if X happens, the view would shift in this direction. These are not predictions.
Intermediate · Weekly
Upside triggers
- If sector bellwethers like VRTX, REGN, and ARGX keep beating earnings and guiding higher, the Healthcare sector momentum should keep lifting SPRO and other Healthcare names. Worth watching these names for early signals.
- If SPRO raises forward guidance on the next earnings call (currently NEW as of 2026-05-13), that's a momentum boost. Street estimates typically follow guidance up and the stock tends to re-rate higher.
- If SPRO beats again next quarter like it did this past one (a big beat of +67% on the 2025-09-30 print), the momentum tends to extend, with Street estimates ratcheting up and the stock typically following.
Downside triggers
- If SPRO cuts guidance on the next call (currently NEW as of 2026-05-13), that's a meaningful negative. The Street tends to walk down estimates and the stock usually takes a leg lower.
- If sector bellwethers like VRTX, REGN, and ARGX start missing or guiding lower, the Healthcare tailwind helping SPRO and other Healthcare names could fade. Watch these names for early warning.
Recent events
(material 8-K / filing activity)Material updates
Recent SEC 8-K filings ranked by likely impact, confidence, and recency.
- 2026-05-131mo agoItem 2.02
and in the press release furnished as Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended, or incorporated by reference in any filing with the U.S. Securities and Exchange Commission made by the Company, whether made before or after the date hereof, regardless of any general incorporation langua…
Earnings preannouncement—
Score history
Whether the overall read has been drifting up or down lately, and how it's changed since last week.
-12 vs last weeklatest as of 2026-06-16
Not investment advice. Scores describe historical and current data; they are not forecasts of future returns. Consult a licensed advisor before making investment decisions.