What Rezolute does

Rezolute (NASDAQ: RZLT) is a clinical-stage biopharmaceutical company developing ersodetug (RZ358), a fully human monoclonal antibody that binds allosterically to the insulin receptor in liver, fat, and muscle tissue to modulate insulin signaling. The company targets two forms of hyperinsulinism (HI): congenital hyperinsulinism (CHI), a rare pediatric genetic disorder affecting approximately 1 in 22,000 births worldwide, and tumor hyperinsulinism driven by insulinomas or non-islet cell tumors in adults. Two Phase 3 registrational trials are in progress: the sunRIZE study in CHI and the upLIFT study in tumor HI. The company holds multiple regulatory designations including FDA Orphan Drug, FDA Pediatric Rare Disease, EU Orphan Drug, EMA PRIME, UK ILAP Innovation Passport, and is engaging with FDA under Breakthrough Therapy framework following the December 2025 sunRIZE readout. Ersodetug's mechanism of action — acting downstream of the pancreas — provides potential pan-etiology efficacy across genetic, acquired, and tumor-driven forms of HI.

Rezolute's revenue model is contingent pharmaceutical drug sales targeting rare disease populations once regulatory approval is secured; the company is currently pre-revenue. Commercial infrastructure buildout is underway through a Chief Commercial Officer with prior ultra-rare disease launch experience (Crysvita at Ultragenyx), a Chief Regulatory Officer with 13 years at Genzyme, and a dedicated VP of Medical & Patient Affairs. Go-to-market positioning targets specialized endocrinology treatment centers and key opinion leaders, supplemented by an Expanded Access Program and The Rezolution patient community platform in collaboration with international advocacy organizations including Congenital Hyperinsulinism International.

The business carries a single-asset, binary-clinical-event risk profile. The December 2025 sunRIZE Phase 3 primary endpoint failure caused an 85–90% stock decline; the FDA subsequently declined to require a new controlled trial and encouraged broader data submission. The June 2026 positive upLIFT interim data and Guggenheim analyst modeling of approximately $850M in peak U.S. sales support a partial recovery narrative. Capital base stood at $120.3M cash and investments as of March 31, 2026, against a market capitalization of approximately $418M in June 2026, with the company's headquarters in Redwood City, California and additional offices in Bend, Oregon and New York.

Name

Rezolute

Legal name

Rezolute, Inc.

Website

https://rezolutebio.com

Company type

Public

Founded year

2017

Operating status

Operating

Headcount range

51–100 employees

Short description

Rezolute is a clinical-stage biopharmaceutical company developing ersodetug, a fully human monoclonal antibody for hyperinsulinism, targeting rare pediatric congenital and adult tumor patient populations suffering severe hypoglycemia.

Ownership category

akta.pro rank

Headquarters

HQ city

Louisville

HQ country

United States

HQ region

North America

Offices3 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Pharmaceutical Drug Sales: Pre-revenue biopharmaceutical company developing er sodetug for treatment of congenital and tumor hyperinsulinism. Once approved, the company expects to generate revenue through pharmaceutical product sales targeting rare disease populations.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

Rezolute is developing ersodetug (RZ358), a fully human monoclonal antibody designed to treat all forms of hyperinsulinism (HI) by binding allosterically to the insulin receptor at liver, fat and muscle tissues to modulate insulin signaling and maintain glucose in a normalized range. The drug is being evaluated in two Phase 3 registrational trials: sunRIZE for congenital HI and upLIFT for tumor HI. The company also operates an Expanded Access Program (compassionate use) for patients with severe hypoglycemia and no alternative treatments.

Product overview

Rezolute is a biopharmaceutical company developing novel therapies for rare diseases, specifically focused on hypoglycemia caused by hyperinsulinism. The company's lead product is ersodetug (RZ358), a fully human monoclonal antibody that acts downstream from the pancreas to modulate insulin receptor signaling and maintain glucose levels. The development pipeline includes two Phase 3 registrational programs: the sunRIZE study for congenital hyperinsulinism and the upLIFT study for tumor hyperinsulinism. The company also operates an Expanded Access Program for compassionate use and supports patient communities through The Rezolution initiative. Currently, no product has received regulatory approval.

Differentiator

Problem solved

Functional benefit

Brands

• The Rezolution: Patient advocacy and community initiative providing updates on therapy innovations, community events, and educational support for the hyperinsulinism community.

Products and services

• Ersodetug (RZ358) Ersodetug (RZ358) is Rezolute's lead investigational product, a fully human monoclonal antibody designed to treat all forms of hyperinsulinism (HI). It binds allosterically to the insulin receptor at target tissues in the liver, fat and muscle to modulate the binding and signaling effects of insulin to help maintain glucose values in a normalized range, acting downstream of the pancreas for potential universal effectiveness. Currently in two Phase 3 registrational trials (sunRIZE for congenital HI and upLIFT for tumor HI).

Quantifiable outcome

• 75% of tumor HI patients achieved complete discontinuation of IV dextrose/TPN support in Expanded Access Program
• +2 more outcomes

Segments2 records

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature1 record

Partnerships

Three partnerships are on record, tiered minor and core.

• NervGen PharmaminorOthersFormer Rezolute executive Keith Vendola joined NervGen Pharma as CFO, indicating personnel exchange between the companies but no active business partnership.
• Congenital Hyperinsulinism International (CHI)coreStrategic or Co-development PartnerPatient advocacy organization founded by caregivers and patients impacted by HI. Rezolute's VP Medical & Patient Affairs previously served 7 years as Board President of CHI, helping launch the HI Global Registry and CHI Centers of Excellence program.
• Patient Advocacy OrganizationscoreStrategic or Co-development PartnerRezolute collaborates with multiple patient advocacy organizations including hiperinsulinismo congenito, hyperinsulinismus.de (Germany), Children's HI Charity (UK), Insulinoma.co.uk, and Neuroendocrine Cancer Foundation. These organizations provide education, research, clinical care, and support to affected communities.

Scale indicators7 records

Recent moves6 records

Expansion highlights7 records

Direct peers

• Crinetics Pharmaceuticals: Clinical-stage biopharma developing therapies for rare endocrine diseases including acromegaly and congenital hyperinsulinism (paltusotine). Similar rare metabolic focus, comparable development stage, and overlapping target patient populations make Crinetics the most direct comparable.
• Soleno Therapeutics: Rare disease biopharma focused on Prader-Willi syndrome and related metabolic disorders. Similar clinical-stage profile, ultra-rare disease commercial model, and comparable market capitalization make Soleno a closely matched peer.

Broad incumbents

• Ultragenyx Pharmaceutical: Established commercial-stage rare disease company with multiple ultra-rare product launches including Crysvita for X-linked hypophosphatemia. Comparable ultra-rare disease commercial infrastructure and shared leadership bench (multiple ex-Ultragenyx executives at Rezolute).
• BioMarin Pharmaceutical: Established rare disease biopharma with commercial products across multiple ultra-rare metabolic and genetic conditions. Comparable orphan drug commercial model and regulatory strategy make BioMarin a benchmark for ersodetug's commercial trajectory.
• Recordati Rare Diseases: Specialty pharma division focused on rare endocrine and metabolic disorders with established commercial presence. Overlap in rare metabolic disease focus and pediatric endocrinology customer base make Recordati a relevant broader incumbent peer.

Emerging players

• Zealand Pharma: Clinical-stage biotech developing peptide therapeutics for metabolic and rare diseases including congenital hyperinsulinism. Direct overlap in HI therapeutic development creates meaningful competitive and strategic comparability.
• Travere Therapeutics: Rare disease biopharma with approved therapies in kidney and metabolic disorders. Similar clinical-to-commercial transition profile and rare disease commercial infrastructure provide a relevant comparable for Rezolute's commercialization planning.
• Ascendis Pharma: Rare endocrine disease biopharma with approved pediatric endocrinology products (Skytrofa, Yorvipath). Comparable focus on rare endocrine/metabolic conditions and pediatric endocrinology prescriber base make Ascendis a relevant peer for commercial benchmarking.
• Amylyx Pharmaceuticals: Clinical-stage rare disease biopharma developing therapies for neurodegenerative and metabolic conditions. Similar clinical-stage profile and small-cap public company structure make Amylyx a useful operational and financial comparable.

Others

• Madrigal Pharmaceuticals: Metabolic disease biopharma focused on NASH/MASH with approved resmetirone therapy. While not directly competitive, comparable public biopharma status and metabolic disease expertise make Madrigal a useful broader metabolic disease comparable for investor sentiment and valuation reference.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/rezolutebio
• Xx.com/rezolutebio

Compliance5 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds19 records

Investors19 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Rezolute