Electra Therapeutics, Inc. 424B4final IPO prospectus

Executive Summary

Electra Therapeutics develops antibodies designed to remove disease-driving immune cells while preserving normal immune function; future revenue depends on approvals and commercial adoption of two investigational candidates. It has no revenue, and clinical expansion drove net loss from $(24.8)M in FY2024 to $(62.0)M in FY2025, followed by $(48.9)M in H1 2026. Its $350M, entirely primary IPO values outstanding equity at an implied $942M and gives IPO buyers 37.2% ownership before option dilution. The investment case rests on ipsoprubart’s promising but small, uncontrolled clinical dataset translating into registrational success—while manufacturing deficiencies and an external-control trial design create material execution risks.

The Offering

• Size and implied valuation: 23.3M primary shares at $15.00 raise $350M gross; 62,766,955 shares outstanding after the base offering imply $942M market capitalization and 37.2% ownership for IPO buyers. Including outstanding, subsequent and IPO-granted options gives 71.6M fully diluted shares, $1.07B capitalization and 32.6% buyer ownership, before ungranted plan reserves. Revenue and earnings multiples are not meaningful for this pre-revenue, loss-making business.
• Proceeds and distribution: estimated net proceeds ≈$320M; the company receives all proceeds, with no secondary sales. A 30-day option covers 3.5M additional primary shares, increasing gross proceeds to $403M and estimated net proceeds to ≈$369M. Underwriters: Jefferies, TD Securities, Evercore and Cantor Fitzgerald; listing: Nasdaq Global Select Market, ETRA.
• Deployment: ≈$220M for ipsoprubart’s secondary hemophagocytic lymphohistiocytosis development through topline results, marketing-application submission and commercial readiness; ≈$25.0M for its T-cell and natural-killer-cell malignancy program; ≈$50.0M for ELA822 trials; the balance supports other development and operations. Management projects funding into 2029, not through completion of all development and commercialization.
• Asset backing: each $15.00 share is backed by $6.53 of net tangible assets after the IPO, an $8.47 gap. Existing holders paid $7.65 per share on average; buyers therefore pay substantially more for the same development-stage assets.
• Capitalization bridge: “after the IPO” assumes preferred conversion plus the base offering, net of expenses. Conversion reclassifies $311M of preferred stock into equity, lifting stockholders’ equity from $(219)M before the IPO to $91.7M before new proceeds; the offering lifts it to $412M and cash plus investments to $418M.
• Timing and resale: prospectus/pricing date 9/17/2026; delivery expected on or about 9/21/2026. The company, officers, directors and substantially all existing securityholders face 180-day lock-ups ending 3/16/2027, subject to exceptions and early release. ≈39.4M pre-offering shares could subsequently become eligible for sale.

Key Financial Highlights

Historical income and cash-flow figures remain unchanged by the IPO. Balance-sheet figures are period-end amounts; H1 2026 ends 6/30/2026.

• Spending acceleration: H1 2026 R&D rose 122% Y/Y, principally from registrational-trial site initiation, enrollment and manufacturing; direct ipsoprubart costs more than tripled. Burn should rise as trials and commercial preparation expand.
• Equity deficit: accumulated losses of $(222)M reduce equity, while $311M of redeemable preferred stock sits outside stockholders’ equity because redemption can be triggered by events outside company control. The deficit is not borrowing: debt is zero and liabilities are $14.8M.
• Cash versus loss: H1 2026 cash burn was below net loss because of non-cash charges, including $2.61M of stock-based compensation, and working-capital timing. The increase in liquidity reflects June’s $49.9M preferred financing, not operating earnings.
• Common-holder accounting: a $9.68M non-cash allocation to preferred holders increased H1 2026 loss attributable to common holders to $(58.6)M. Pre-IPO per-share losses are distorted by only 29,329 common shares outstanding.
• Funding history: $40.0M of 2025 convertible-note principal plus accrued interest converted into preferred stock in October 2025; the IPO strengthens liquidity but does not eliminate future financing needs.

Business Model and Growth Drivers

Electra’s platform targets signal regulatory proteins to deplete activated immune cells rather than block their normal signaling. Management seeks value through product commercialization, additional indications and selective collaborations.

• Lead program: ipsoprubart targets secondary hemophagocytic lymphohistiocytosis, a life-threatening inflammatory syndrome without broadly approved treatment. Twelve frontline malignancy-associated patients achieved 100% eight-week survival and response; the uncontrolled sample cannot establish comparative benefit. Earlier relapsed/refractory outcomes were worse, prompting a frontline focus.
• Registrational strategy: SURPASS uses an open-label treatment cohort and COMPASS historical controls. Its primary efficacy population is expected to include ≈47 lymphoma-associated patients against at least 94 eligible controls; enrollment completion is expected in the second half of 2027.
• Expansion: initial ipsoprubart malignancy-trial data are expected in the second half of 2027. Eight earlier lymphoma patients showed 100% tumor response, but concurrent cancer therapies obscure attribution. ELA822 healthy-volunteer data are expected in H1 2027, with patient trials planned for mid-2027.
• Commercial concentration: management estimates ≈12,600 diagnosed U.S. cases in 2025; ≈64% receive care at academic centers, potentially supporting a focused launch. These are company estimates, not demonstrated demand. Electra relies entirely on third-party manufacturing.

Governance and Control

• Voting: one common-share class, one vote per share. A staggered board, restrictions on director removal and board-issued preferred stock can impede shareholder-driven changes.
• Ownership: reported post-IPO stakes include Westlake 10.1%, OrbiMed 8.8% and Redmile 7.6%; concentrated institutional ownership creates influence without a single majority holder.
• Compensation dilution: 2.86M IPO option grants accompany a 13.4M-share equity-plan reserve, including those grants, and a 0.612M-share employee purchase reserve; automatic annual increases can expand dilution.
• Strategic rights and reporting: Sanofi retains specified scientific-data access and transaction-participation opportunities. Emerging-growth-company exemptions reduce disclosures and remove auditor attestation of internal controls.

Risk Assessment

• Going concern and funding: the FY2025 auditor flagged substantial doubt, and pre-IPO resources cannot support the planned business for 12 months; projected post-IPO runway depends on spending assumptions.
• Registrational validity: regulators may reject historical controls, statistical adjustments or the survival endpoint, requiring additional trials despite favorable results.
• Manufacturing interruption: the drug-product manufacturer received an FDA Official Action Indicated classification after a March 2026 inspection; remediation shutdown and unresolved deficiencies could delay supply or approval.
• Pipeline concentration: two unapproved candidates carry the business, and small clinical cohorts and animal studies may not predict efficacy or safety.
• Market conversion: uncertain patient estimates, familiar low-cost off-label treatments and reimbursement constraints could limit adoption after approval.
• Valuation and dilution: the implied $942M equity value requires clinical and commercial success before revenue exists; option issuance, future financing and the lock-up release can dilute ownership or increase selling pressure.
• Supply-chain dependence: no redundant bulk-drug source and ELA822’s reliance on WuXi expose development to supplier failures and U.S.–China restrictions.

Investor Actionables

• Clinical milestones: watch H1 2027 ELA822 data and second-half 2027 ipsoprubart updates for reproducible activity, safety and enrollment progress.
• Manufacturing readiness: seek evidence of inspection remediation and uninterrupted supply before treating approval timelines as dependable.
• Financing and supply: track quarterly burn against the into-2029 runway and potential selling around 3/16/2027; faster spending or early refinancing would weaken the funding cushion.