Executive Summary

Q1 2025 revenue was $17.4M, up 33.8% year over year versus $13.0M in Q1 2024, driven principally by the Astellas collaboration; cash and marketable securities were $249.0M with runway guided “into early 2027” following the restructuring .
Versus S&P Global consensus, Sutro posted a significant revenue beat ($17.4M vs $11.6M*) but an EPS miss (company-reported diluted EPS -$0.91 vs consensus -$0.63*; S&P’s “actual” normalized EPS -$0.80*), reflecting $21.0M restructuring charges and non-cash interest expense tied to sale of future royalties .
Strategic pivot executed: luvelta funding deprioritized; focus sharpened to next‑gen exatecan and dual‑payload ADCs; STRO‑004 IND planned for 2H 2025 and three INDs expected over the next three years; a $7.5M Astellas milestone was triggered by an IND‑enabling tox study .
Organizational reset underway: ~50% headcount reduction, manufacturing fully externalized, San Carlos facility to be decommissioned by year‑end 2025; stockholders’ equity turned to a deficit (-$25.8M), highlighting balance sheet optics despite cash runway .

What Went Well and What Went Wrong

What Went Well

Revenue beat vs consensus and +34% YoY growth on collaboration momentum; “Revenue was $17.4 million…with the 2025 amount related principally to the Astellas collaboration” .
Pipeline clarity and acceleration: “We selected STRO‑004…as our lead clinical candidate…on track to deliver three new INDs over the next three years” .
Platform validation and external milestones: initiation of an IND‑enabling tox study within Astellas iADC triggered a $7.5M milestone, underscoring partner appetite for Sutro’s dual‑payload approach .

Quote: “STRO‑004…supported by strong preclinical data that point to its best‑in‑class potential…our XpressCF+ cell‑free platform [enables] novel dual‑payload ADCs” — Jane Chung, CEO .

What Went Wrong

EPS miss vs consensus and widening net loss: net loss of $76.0M and diluted EPS of -$0.91 weighed by $21.0M restructuring charges and $9.3M non‑cash interest tied to royalty monetization .
Equity optics deteriorated: total stockholders’ equity swung to a deficit of -$25.8M at March 31, driven by deferred royalty obligations ($190.3M) and restructuring accruals .
Execution and resourcing overhang on luvelta: deprioritization raises uncertainty until partnered; management acknowledged capital intensity and macro constraints as drivers of the pivot .

Financial Results

Quarterly P&L vs Prior Periods and Estimates

Metric	Q3 2024	Q4 2024	Q1 2025
Revenue ($USD Millions)	$8.52	$14.81*	$17.40
Diluted EPS ($USD)	-$0.59	-$0.88*	-$0.91
Loss from Operations ($USD Millions)	-$67.92	-$65.26*	-$68.51
Total Operating Expenses ($USD Millions)	$76.44	$80.07*	$85.91

Notes: Asterisks denote values retrieved from S&P Global.

Q1 2025 Actual vs Consensus

Metric	Consensus (S&P Global)	Actual (Company)
Revenue ($USD Millions)	$11.61*	$17.40
EPS ($USD)	-$0.63*	-$0.91
EPS “Actual” (S&P Normalized) ($USD)	—	-$0.80*
Number of Estimates (Revenue / EPS)	9 / 8*	—

Notes: Asterisks denote values retrieved from S&P Global.

Year-over-Year Comparison (Q1 2025 vs Q1 2024)

Metric	Q1 2024	Q1 2025
Revenue ($USD Millions)	$13.00	$17.40
Total R&D + G&A ($USD Millions)	$69.60	$64.90
Restructuring & Related Costs ($USD Millions)	—	$21.04
Net Loss ($USD Millions)	-$58.21	-$75.97
Diluted EPS ($USD)	-$0.95	-$0.91

KPIs and Balance Sheet

KPI	Q3 2024	Q4 2024	Q1 2025
Cash, Cash Equivalents & Marketable Securities ($USD Millions)	$388.25	$316.90	$248.97
Deferred Revenue ($USD Millions)	$90.56	$82.32	$77.54
Deferred Royalty Obligation ($USD Millions)	$171.97	$180.81	$190.30
Accounts Receivable ($USD Millions)	$6.66	$8.62	$13.56
Stockholders’ Equity ($USD Millions)	$111.22	$44.60	-$25.81

Guidance Changes

Metric	Period	Previous Guidance	Current Guidance	Change
Cash Runway	Company-level	“into at least Q4 2026” (3/13/25)	“into early 2027” (5/8/25)	Raised
IND – STRO‑004 (Tissue Factor exatecan ADC)	Program	File IND 2H 2025 (3/13/25)	File IND 2H 2025 (reaffirmed 5/8/25)	Maintained
IND – STRO‑006 (ITGB6 ADC)	Program	Clinical development in 2026 (3/13/25)	Clinical development in 2026 (5/8/25)	Maintained
IND – First wholly‑owned dual‑payload ADC	Program	IND in 2027 (3/13/25)	IND in 2027 (5/8/25)	Maintained
Organizational Headcount	Company-level	~50% reduction (3/13/25)	~50% reduction (5/8/25)	Maintained
Manufacturing	Company-level	Exit internal GMP facility by YE 2025 (3/13/25)	Decommission facility by YE 2025; capabilities scaled externally (5/8/25)	Maintained
Restructuring Cash Payments	Company-level	$40–$45M expected, majority in 2025 (3/13/25)	$21.0M recognized in Q1; additional costs expected (5/8/25)	Progressing as planned

Earnings Call Themes & Trends

Topic	Previous Mentions (Q3 2024)	Previous Mentions (Q4 2024)	Current Period (Q1 2025)	Trend
Pipeline focus: Next‑gen ADCs	Introduced three planned INDs; highlighted STRO‑004 DAR8 exatecan and dual‑payload/iADC concepts	Restructuring and pivot to STRO‑004/006 and dual‑payload; IND timing laid out	Reaffirmed timelines; STRO‑004 prioritized; AACR/PEGS preclinical data	Consistent, accelerating
Luvelta strategy	Multi‑indication development underway; partner search initiated	Deprioritized due to capital needs; active partnering discussions	Open to partnership opportunities; SGO late‑breaker presented	Shift to partner‑led
Partnerships (Astellas, Ipsen)	Aggregate ~$975M from collaborators through 9/30/24	Continued BD for non‑dilutive capital	Astellas iADC tox study started; $7.5M milestone	Strengthening
Manufacturing & ops	—	Externalization; exit San Carlos by YE 2025	Decommission by YE 2025; capabilities established externally	Execution underway
Cash runway & burn	$388.3M cash at 9/30/24	Runway “into at least Q4 2026”; spend to decline post‑Q1	Runway “into early 2027” post‑restructuring	Improved
Regulatory/medical conferences	ESMO combo data (luvelta+bev)	SGO data upcoming	AACR/PEGS posters (STRO‑004, dual‑payload; STRO‑006 PK/anti‑tumor)	Active cadence

Management Commentary

“We selected STRO‑004…as our lead clinical candidate, supported by strong preclinical data that point to its best‑in‑class potential…highlighted the unique capabilities of our XpressCF+ platform to develop novel dual‑payload ADCs” — Jane Chung, CEO .
“We are on track to deliver three new INDs over the next three years, starting with STRO‑004…with the recent initiation of an IND‑enabling toxicology study…triggering a milestone payment to Sutro” — Jane Chung, CEO .
“We are filing an IND later this year…particularly encouraged by improvements in safety…compared to benchmark ADCs already approved [targeting] tissue factor” — Hans‑Peter Gerber, CSO .
“We will reduce our workforce by nearly 50%…externalizing our manufacturing…decommissioning San Carlos later this year” — Jane Chung, CEO .

Q&A Highlights

Luvelta path: Management emphasized deprioritization due to capital intensity, not data concerns; actively pursuing a partner to lead future development .
STRO‑004 timing and data: IND filing planned for 2H 2025 with initial clinical reads in 2026/2027; safety/efficacy improvements vs benchmark tissue factor ADCs highlighted by CSO .
Cost trajectory and runway: 2024 spend (~$300M) was “clear majority” luvelta‑related; 2025 includes $40–$45M restructuring charges; dramatic expense decline expected post‑Q1, supporting runway into at least Q4 2026 (superseded to “early 2027” in May update) .
BD strategy: Active discussions to partner luvelta; continued use of collaborations for non‑dilutive capital (Astellas milestone exemplifies traction) .

Estimates Context

For Q1 2025, S&P Global consensus revenue was $11.61M*, versus actual company‑reported $17.40M, a notable beat driven by collaboration revenue timing .
EPS consensus was -$0.63*, while company‑reported diluted EPS was -$0.91; S&P’s normalized “actual” EPS was -$0.80*, indicating basis differences between reported and normalized EPS. Count of estimates: Revenue 9, EPS 8*.

Notes: Values retrieved from S&P Global.

Key Takeaways for Investors

Near‑term catalyst stack shifts from luvelta to platform‑led ADCs: STRO‑004 IND (2H 2025), STRO‑006 clinical start (2026), first wholly‑owned dual‑payload IND (2027) .
Collaboration optionality is an important funding lever; Astellas milestone ($7.5M) and ongoing programs underscore external validation and non‑dilutive capital pathways .
The financial profile will change as luvelta wind‑down flows through 2025; Q1 showed $21.0M restructuring costs and $9.3M non‑cash royalty interest; expect lower operating spend exiting 2025 .
Balance sheet optics (stockholders’ deficit) warrant monitoring, but liquidity runway extended to early 2027 post‑restructuring and externalized manufacturing .
Trading lens: Revenue beats in collaboration‑heavy quarters can be lumpy; headlines and scientific dataflow (AACR/PEGS) plus IND milestones likely to be key stock drivers in 2H 2025 .
Partnering luvelta remains a swing factor; announcements could add milestones and reduce expense burden, de‑risking cash trajectory .
Watch conference participation (TD Cowen, Jefferies) for BD tone and timeline updates, especially around STRO‑004 IND preparations and external manufacturing readiness .

Notes:

No Q1 2025 earnings call transcript was available in our document catalog; analysis relies on the Q1 2025 8‑K press release and prior quarter call [List: 0 Q1 2025 call; Q4 2024 call read fully].
All document facts are cited; S&P Global consensus/actual estimate figures are marked with asterisks and noted as “Values retrieved from S&P Global.”

SUTRO BIOPHARMA, INC. (STRO)·Q1 2025 Earnings Summary