Electra Therapeutics: Pioneering SIRP-Targeted Therapy for sHLH

Every biotech funding round tells a story. Behind the dollar figures are hypotheses about how biology can be rewritten—and which problems the industry finally believes it can solve.

This series follows the companies turning those hypotheses into real treatments. Next up: Electra Therapeutics.

Electra Therapeutics' Bold Goal: Transform Treatment for sHLH

Electra Therapeutics, a South San Francisco-based clinical-stage biotechnology company, is pioneering first-in-class therapies targeting signal regulatory proteins (SIRP) for severe immunological diseases and cancer. The company has emerged as a leader in developing ELA026, an investigational antibody therapy for secondary hemophagocytic lymphohistiocytosis (sHLH), a life-threatening hyperinflammatory condition with no approved treatments.

sHLH is a rare, devastating disease—mortality rates range from 30% to 75% within the initial two months of diagnosis, with malignancy-associated HLH (mHLH) patients facing the poorest outcomes. The disease triggers a catastrophic cytokine storm that can lead to multiple organ failure and death without immediate intervention.

Why sHLH Needs New Approaches

sHLH can be triggered by cancer (mHLH), infection, autoimmune disease, or immunotherapy, and is characterized by uncontrolled immune activation. The condition causes pathological immune cells—specifically myeloid cells and T lymphocytes—to release excessive inflammatory cytokines, creating a systemic inflammatory response that damages tissues and organs.

Currently, there are no approved therapies specifically for sHLH. Available treatments may include chemotherapy and single cytokine-directed therapies, but these approaches often fail to adequately control the overwhelming immune reaction. Historical data shows response rates of only 40-50% with standard therapies, with approximately 50% of mHLH patients surviving to two months. That leaves a critical gap in care—and a clear opportunity for new solutions.

Electra Therapeutics is aiming to fill that gap by developing a therapy that addresses the root cause of the cytokine storm, not just individual cytokines.

A Novel Therapeutic Approach: SIRP-Targeted Cell Depletion

Electra Therapeutics is taking a groundbreaking approach by targeting signal regulatory proteins (SIRP) on immune cells to selectively deplete the pathological cells driving sHLH. The company's lead asset, ELA026, is a monoclonal antibody that binds to specific SIRP family receptors (SIRPα, SIRPβ1, and SIRPγ) expressed on myeloid cells and T lymphocytes.

Rather than using SIRP therapeutics to promote immune activation in oncology—the typical approach—Electra uses SIRPs as cell surface targets to deplete pathological immune cells. This puts the brakes on an overactive immune system. When ELA026 binds to these receptors, it promotes the removal of pathologically activated cells through antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP).

This targeted approach allows for a rapid onset of action, which is crucial in treating the acute nature of sHLH. Preclinical studies demonstrated reversibility of the pharmacodynamic effect following washout, suggesting that ELA026 treatment is not associated with long-term immunosuppression.

Exceptional Clinical Results: 100% Survival in High-Risk Patients

The clinical validation of Electra's approach has been nothing short of remarkable. In a completed Phase 1b study, ELA026 demonstrated extraordinary efficacy in patients with mHLH, the most deadly sHLH subtype.

In treatment-naive mHLH patients receiving frontline treatment with ELA026, the therapy achieved a 100% overall response rate by week 4, compared to historical response rates of 40-50%. Even more compelling, 100% of these high-risk patients were discharged from the hospital, with 100% survival at eight weeks.

The Phase 1b study also showed that ELA026 rapidly attenuated inflammation, with pharmacodynamic and HLH-related biomarkers correlating with clinical responses. ELA026 demonstrated a favorable safety profile across a range of sHLH patients in this life-threatening hyperinflammatory condition.

Leadership & Expertise

Electra Therapeutics is led by a seasoned team of professionals with proven track records in drug discovery and development:

• Kathy Dong, PharmD, MBA, President and Chief Executive Officer: Dong brings extensive experience in corporate development, portfolio management, and product commercialization. She previously served as Chief Operating Officer at Star Therapeutics and Vice President of Commercial Development at True North Therapeutics. She spent nine years at Gilead Sciences, where she led the launch of SOVALDI and HARVONI, two of the most successful launches in biopharmaceutical history.
• Graham Parry, PhD, Chief Scientific Officer: Parry has deep experience in drug development and has been instrumental in leading multiple drug candidates through clinical trials and toward regulatory approval.
• Kim-Hien Dao, DO, PhD, Chief Medical Officer: Dr. Dao has demonstrated outstanding clinical and translational research expertise and has been instrumental in guiding ELA026 through the clinic as a first-in-class antibody therapy.
• Nancy Stagliano, PhD, Executive Chair: Stagliano serves as Executive Chair of Electra's Board of Directors, providing strategic guidance to the company.

The company was spun out from Star Therapeutics, a hub-and-spoke biotech that functions as a central innovation engine developing homegrown antibodies against novel targets.

Funding & Backing

Electra Therapeutics has raised substantial capital to advance its pioneering therapies. The company announced an impressive $183 million Series C financing in October 2025, co-led by EQT Life Sciences, with participation from new and existing investors. This funding follows an $84 million Series B round in 2022 and earlier undisclosed Series A financing from Star Therapeutics.

In total, Electra has raised over $267 million in funding to date. This substantial backing highlights the growing confidence from investors in the company's novel approach and the strong clinical validation demonstrated by ELA026.

The Series C proceeds will fund a global pivotal Phase 2/3 trial of ELA026 as a frontline treatment for sHLH, expand the pipeline into hematologic cancers, and support advancement of additional SIRP-targeted therapies.

Strong Regulatory Recognition

ELA026 is the first investigational therapy to receive both Breakthrough Therapy and PRIME designations for sHLH. The investigational therapy has received multiple designations from regulatory authorities:

• FDA Breakthrough Therapy Designation (October 2025): Facilitates development and expedites review of medicines for serious conditions with unmet medical needs.
• EMA PRIME Designation: The European Medicines Agency's Priority Medicines (PRIME) designation provides early and enhanced support for promising medicines addressing unmet medical needs.
• FDA Fast Track Designation (November 2024): Enables more frequent interactions with the FDA and potential rolling submission of the marketing application.
• FDA Orphan Drug Designation: Provides development incentives for therapies treating rare diseases.

These designations underscore ELA026's transformative potential and the high level of regulatory support for its development.

Pipeline & Milestones

Electra Therapeutics announced in October 2025 that the first patients have been dosed in SURPASS, a pivotal Phase 2/3 clinical trial evaluating ELA026 in sHLH. The SURPASS study is enrolling patients at research sites across the United States and Europe, and is designed to assess the safety, efficacy, pharmacokinetics, and pharmacodynamics of ELA026 in patients with sHLH.

Beyond sHLH, Electra is evaluating ELA026 in hematologic cancers, where initial clinical data have shown promising potential. The company's pipeline expansion strategy focuses on applying its novel SIRP-targeting approach to address broader inflammatory conditions and cancer indications with high unmet need.

The company's strategic vision extends beyond ELA026, with plans to leverage its platform to develop additional SIRP-targeted therapies for immune-mediated diseases and cancer.

Market Opportunity & Competitive Edge

Electra Therapeutics holds a distinct competitive advantage with ELA026 as the first-in-class SIRP-targeted therapy for sHLH, representing a fundamentally different approach than blocking individual cytokines.

The early clinical results showing 100% survival at eight weeks in frontline-treated mHLH patients—compared to approximately 50% with historical therapies—demonstrate ELA026's potential to deliver substantial clinical benefit. The therapy's ability to rapidly extinguish hyperinflammation enables sHLH patients to pursue curative therapies for their underlying cancer.

Furthermore, ELA026's favorable safety profile differentiates it from chemotherapy-based approaches that can be difficult for critically ill patients to tolerate.

Looking Ahead

Electra Therapeutics has demonstrated remarkable momentum, going from a novel idea to pivotal study readiness in five years. By pioneering SIRP-targeted cell depletion to modulate inflammation, the company has clinically validated an entirely new therapeutic approach for treating severe immune dysregulation.

With substantial capital, strong clinical data, multiple regulatory designations, and an experienced leadership team, Electra is well-positioned to deliver the first approved therapy for sHLH. The initiation of the SURPASS pivotal trial represents a critical step toward bringing this treatment to patients facing a life-threatening disease with no current approved options.

As Electra expands its pipeline into hematologic cancers and broader inflammatory conditions, the company's novel SIRP-targeting platform may unlock new therapeutic possibilities across multiple diseases driven by pathological immune activation.