Upstream Bio (UPB) Stock Fundamentals, Analysis & Risk Signals

Health score, price, valuation, risk signals, and key metrics at a glance.

Upstream Bio

NasdaqGS•Healthcare•Biotechnology

$5.73-0.02(<0.01%)Pre-market

Market Cap

$312.67M

P/S

99.0x

P/B

1.2x

Upstream Bio, Inc., a clinical-stage biotechnology company, develops treatments for inflammatory diseases focusing on severe respiratory disorders. It offers verekitug, which is in Phase 2 trials for the treatment of severe asthma and chronic rhinosinusitis with nasal polyps and chronic obstructive pulmonary disease and in Phase I clinical trial for treating chronic obstructive pulmonary disease. The company was incorporated in 2021 and is headquartered in Waltham, Massachusetts.

How this company scores

WeakMetricSide Score: 32/100

Strongest: Balance Sheet & Red Flags (15/25); weakest: Profitability (4/25).

Profitability4/25

Growth5/25

Balance Sheet & Red Flags15/25

Cash & Earnings Quality8/25

Strengths

Interest easily coveredNet cash position

Valuation vs. 5-year range

Today's multiple positioned against its own trailing range — a visual premium/discount check.

P/S · 99.0x5y range 99.0x – 517.8x

Currently below its 5-quarter median.

P/B · 1.2x5y range 0.5x – 4.3x

Currently near its 7-quarter median.

Watch items

Data-driven signals worth keeping an eye on across the last 8 quarters

High Risk

Margin Pressure

Red Flag

The company posted negative operating margins in recent quarters — core operations are unprofitable.

Earnings Quality

Red Flag

Free cash flow has been negative in 8 of the last 8 quarters — earnings are not translating to cash.

Price & Volume

Market Cap $312.67M

Metrics at a Glance

as of June 2026

Revenue & Profit

Revenue, EBITDA, operating income, net income, EPS, and shares

TTM Revenue: $3.16M
Q. Revenue: $773,000
TTM EBITDA: $-169.78M
TTM Op. Income: $-169.98M
Q. Op. Income: $-42.37M
TTM Net Income: $-156.50M
Q. Net Income: $-39.70M
EPS: $-0.73
Shares Out.: $54.57M

$3.16M in TTM revenue declined 18.5% YoY, reaching $773,000 last quarter. TTM EBITDA of $-169.78M and TTM operating income of $-169.98M show growth is flowing through to the bottom line. However, net income is negative at $156.50M — growth is not yet reaching the bottom line. Over the past year, TTM revenue is down 18% — a weakening trend.

Margins

Gross, EBITDA, operating, and net margin trends

EBITDA Margin: -5474.5%
Op. Margin: -5481.0%
Net Margin: -5136.1%

Op. margin of -5481.0% is down 748.1% YoY — costs are rising relative to revenue. Net margin at -5136.1% Over the past year, operating margin is down 16% — a weakening trend.

Price Ratios

P/E, P/S, P/B, EV/EBITDA, FCF yield, and earnings yield

P/E Ratio: N/A
P/S Ratio: 99.0x
P/B Ratio: 1.2x

P/S of 99.0x and P/B of 1.2x. P/S is high, meaning growth expectations are priced in.

Assets & Liabilities

Total assets, cash, debt, book value, and leverage

Total Assets: $281.17M
Cash: $79.40M
Long-Term Debt: N/A
Book Value: $270.96M
D/E Ratio: N/A
Debt/EBITDA: N/A

Cash Flow

Operating cash flow, free cash flow, FCF margin, and earnings quality

Op. Cash Flow: $-35.62M
TTM Free Cash Flow: $-136.46M
FCF Margin: -4321.2%
FCF / Net Income: 0.9

TTM FCF of $-136.46M on $-35.62M in operating cash flow. The FCF / Net Income ratio of 0.9x means free cash flow covers net income — earnings are backed by cash. Over the past year, free cash flow is up 3% — an improving trend.