Executive Summary

Q3 2025 execution remained strong: Phase 2a POC for SION-719 initiated, Phase 1 dual-combination trial for SION-451 started, and DDI study completed enabling combination dosing with Trikafta; FDA cleared IND for SION-451 to advance to later-stage development .
GAAP net loss per share was -$0.46, modestly better than Wall Street consensus of -$0.475, a beat of $0.015; revenue remains pre-commercial with no reported product revenue and consensus at $0.0* .
Cash, cash equivalents, and marketable securities were $325.0M, with runway guided “into 2028,” tracking down from $354.7M in Q1 and $337.3M in Q2 as R&D and G&A scale with development pace .
Near-term stock catalysts center on mid-2026 topline readouts from the SION-719 Phase 2a and SION-451 dual-combo trials; non-dilutive runway messaging reduces financing overhang risk, while clinical differentiation narrative (CFTR function and half-life toward wild-type) supports medium-term thesis .

What Went Well and What Went Wrong

Initiated Phase 2a POC for SION-719 as add-on to SOC and Phase 1 dual combinations for SION-451; both trials guided to topline in mid-2026, maintaining program cadence .
DDI study confirmed SION-719 can be dosed with Trikafta per label; FDA cleared IND for SION-451, removing key regulatory gating risks .
CEO tone remained confident: “We maintain our track record of strong execution… we have initiated both the PreciSION CF Phase 2a… and the Phase 1 trial of SION-451… results from both trials in mid-2026” .

Operating spend stepped up vs earlier quarters (R&D $16.0M; G&A $7.8M), reflecting pipeline advancement; net loss widened sequentially to $20.3M, though improved YoY vs $25.4M .
Cash declined sequentially ($354.7M Q1 → $337.3M Q2 → $325.0M Q3) as programs advance, though management reiterated runway into 2028 .
Limited visibility on commercial timelines beyond mid-2026 data and no product revenue, keeping valuation leveraged to clinical readouts rather than fundamentals .

Metric	Q3 2024	Q1 2025	Q2 2025	Q3 2025
Research & Development ($USD Millions)	$24.6	$13.7	$15.4	$16.0
General & Administrative ($USD Millions)	$3.4	$6.0	$6.5	$7.8
Total Operating Expenses ($USD Millions)	$28.0	$19.7	$21.9	$23.8
Interest Income ($USD Millions)	$2.4	$3.0	$3.7	$3.5
Other Income ($USD Millions)	$0.2	$0.2	$0.2	$0.1
Net Loss ($USD Millions)	$(25.4)	$(16.5)	$(18.1)	$(20.3)
Net Loss per Share (GAAP, $)	$(5.67)	$(0.62)	$(0.41)	$(0.46)
Weighted-Average Shares (Millions)	4.49	26.60	44.12	44.26

Note: Margin metrics (EBITDA/EBIT/Net margin) are not meaningful for pre-revenue biotech.

Metric	Q1 2025	Q2 2025	Q3 2025
Cash, Cash Equivalents & Marketable Securities ($USD Millions)	$354.7	$337.3	$325.0
Working Capital ($USD Millions)	$264.2	$259.2	$242.5
Total Assets ($USD Millions)	$369.7	$352.0	$339.3
Total Stockholders’ Equity ($USD Millions)	$351.8	$336.4	$321.7

Metric	Consensus*	Actual
Primary EPS (GAAP)	-$0.475*	-$0.46
Revenue ($USD Millions)	$0.0*	n/a (pre-revenue; no product revenue disclosed)

Values with * retrieved from S&P Global.

Metric	Period	Previous Guidance	Current Guidance	Change
Cash Runway	Multi-year	“into 2028” (Q1, Q2)	“into 2028” (Q3)	Maintained
SION-719 Phase 2a POC initiation	2H 2025	“on track 2H 2025” (Q1, Q2)	Initiated Oct 2025; topline mid-2026	Achieved; timeline maintained
SION-719 DDI study	Pre-Phase 2a	“on track to complete pre-initiation” (Q2)	Completed; confirms dosing with Trikafta per label	Achieved
SION-451 Dual-Combination Phase 1 initiation	2H 2025	“on track 2H 2025” (Q1, Q2)	Initiated Aug 2025; topline mid-2026	Achieved; timeline maintained
SION-451 IND status	Regulatory	Not stated (Q1/Q2)	IND cleared to support later-stage development	New positive update
Topline data timing (SION-719, SION-451)	Mid-2026	Mid-2026 (Q1/Q2)	Mid-2026 (Q3)	Maintained

Note: No Q3 2025 earnings call transcript was available in our sources; themes below reflect management’s press releases and IR disclosures .

Topic	Previous Mentions (Q1 & Q2)	Current Period (Q3)	Trend
Pipeline progress (NBD1 stabilizers)	Completed Phase 1 dosing; positive Phase 1 data; preparing P2a and dual-combo starts	P2a (SION-719) and dual-combo Phase 1 (SION-451) initiated; topline mid-2026	Executing to plan
Regulatory interactions	n/a prior	FDA cleared IND for SION-451	Positive regulatory momentum
Trikafta combination enablement	DDI planned/on track	DDI completed; dosing per label confirmed	Risk retired
Clinical differentiation narrative	Preclinical/Phase 1 PK supports potential CFTR function & half-life toward wild-type	Reinforced at NACFC; CFTR half-life up to wild-type in preclinical; well tolerated; exposure targets exceeded	Strengthening
Cash runway	Into 2028 reiterated	Into 2028 reiterated	Stable
Leadership/BD	n/a	New Chief Business Officer appointed (Caroline Stark Beer)	Build-out continues

CEO Mike Cloonan: “We maintain our track record of strong execution… initiated both the PreciSION CF Phase 2a… and the Phase 1 trial of SION-451… looking forward to sharing results… in mid-2026.”
On community engagement and mission: “Our recent engagement with the CF community… reinforced the importance of our science and our mission to revolutionize the treatment paradigm for people living with CF.”
Q2 context: “These data reinforce our confidence in advancing both NBD1 stabilizers into the next stages of development… topline results… mid-2026… Supported by a clear development plan and a strong financial position.”
Q1 context: “We continue to execute across our pipeline… completed dosing in our Phase 1 trials… initiating our Phase 2a POC trial and the combination MAD Phase 1 program later this year.”

No Q3 2025 earnings call transcript or Q&A content was available in our document catalog or IR site at the time of review; no Q&A themes can be extracted .

EPS modest beat: -$0.46 actual vs -$0.475 consensus; magnitude ~$0.015 driven by higher interest income and the absence of one-time IP R&D charges seen YoY in 2024 .
Revenue consensus at $0.0 aligns with pre-commercial status; company did not disclose product revenue .
Target price consensus mean $42.57 and 7 estimates; recommendation text unavailable in our dataset*.

Values with * retrieved from S&P Global.

Execution remains on pace with two clinical catalysts guided for mid-2026 (SION-719 P2a add-on to SOC; SION-451 dual-combos), and regulatory/DDI risks de-risked (IND clearance; Trikafta-combo enabled) .
Liquidity is ample with $325.0M cash and runway into 2028, supporting multi-readout path without near-term financing pressure .
Sequential operating expense increases reflect accelerated development; monitor expense trajectory versus planned clinical activities into 2026 .
Narrative differentiation is strengthening: management highlights potential CFTR function and half-life improvements toward wild-type levels, reinforcing competitive positioning ahead of proof-of-concept .
Short-term trading: modest EPS beat and program milestones may support sentiment; stock likely to trade on clinical updates and conference visibility rather than financials .
Medium-term thesis: risk-reward hinges on mid-2026 efficacy signals in CF; success could catalyze partner interest or accelerate proprietary combination strategies .
Continue tracking IR updates and conference participation for incremental clinical, regulatory, and BD signals in 1H 2026 .