June 17, 2026
Press release

First patient enrolled in Oncopeptides’ glioblastoma study

Science

STOCKHOLM — June 17, 2026 — Oncopeptides AB (publ) (Nasdaq Stockholm: ONCO), a biotech company specializing in difficult-to-treat cancers, today announces that the first patient has been enrolled in the clinical “Window-of-Opportunity” (WoO) study evaluating its proprietary Peptide Drug Conjugate (PDC) platform in glioblastoma.

“Enrolling the first patient in our glioblastoma study is an important step that shifts our brain cancer program from pre-clinical and a regulatory milestone to active clinical assessment” says Sofia Heigis, CEO of Oncopeptides. “Following our swift regulatory approval, this trial allows us to efficiently generate human clinical data in a highly underserved indication, potentially demonstrating the true versatility of our PDC platform as we look to expand our pipeline beyond multiple myeloma.”

The WoO study, named OP-701 (INSULA), represents the first clinical evaluation of a PDC in glioblastoma, marking a major strategic milestone as Oncopeptides expands its core technology platform beyond multiple myeloma. The focused trial will enroll approximately 10 patients to provide initial human proof-of-concept to assess that the company’s technology successfully penetrates the human blood-brain barrier (BBB) in glioblastoma patients and have cytotoxic (cell killing) activity in tumor cells.

The BBB remains the primary clinical obstacle and causes most traditional oncological drugs to fail in this disease.
By utilizing an approved drug from Oncopeptides’ platform as a “clinical probe,” the study employs an innovative and highly efficient design to capture drug activity directly within the tumor tissue from patients scheduled for surgery for recurrent disease. This approach aims to validate the underlying biological mechanism in a rapid, cost-efficient manner before advancing a PDC asset into formal dose-finding and potential further clinical trials.

Glioblastoma is the most aggressive and devastating form of brain cancer, characterized by rapid tumor growth, invariable relapse, and a total lack of curative options, with a median survival rate of just 12–15 months.

The global glioblastoma market represents a profound unmet medical need and is estimated to be worth more than 8 billion USD by 2035. Oncopeptides’ PDC molecules are believed to be uniquely equipped to pass the blood-brain barrier due to their small size and lipophilicity, entering the target cancer cells freely to deliver their cytotoxic payload directly where it is needed.

The trial is conducted at Oslo University Hospital in Norway.

For more information, including questions and answers for investors, please visit www.oncopeptides.com.

Questions and answers

It marks the formal transition of Oncopeptides’ brain cancer pipeline program from pre-clinical and regulatory planning into active clinical assessment. Following the swift regulatory approval from Norwegian authorities in May, patient dosing has begun on schedule, validating the team’s operational execution.
Traditional oncology trials are capital-intensive and take years to yield results. The Window-of-Opportunity (WoO) design is a lean, highly strategic framework. By utilizing an already approved drug from the PDC platform as a “clinical probe” in approximately 10 patients scheduled for surgery, the company can capture drug activity directly within human tumor tissue. This provides a rapid, cost-efficient proof-of-concept for blood-brain barrier penetration and cytotoxic activity before committing significant capital to larger trials.
Successfully executing this study clinically would demonstrate that the proprietary Peptide Drug Conjugate (PDC) platform is a versatile therapeutic vehicle, not a single-indication technology. Proving drug delivery across the blood-brain barrier allows the company to establish a scientific foothold in the global glioblastoma market, which is projected to be worth more than 8 billion USD by 2035.
The blood-brain barrier is the primary reason why over 90% of traditional oncology drugs fail in glioblastoma, as they simply cannot reach the tumor. Because Oncopeptides’ PDC molecules are specifically engineered to be lipophilic and cross this barrier freely, proving this mechanism in humans sets the company apart from standard therapies and positions the PDC platform as a highly valuable delivery technology in a multi-billion dollar market.

Share

Select language or region
Region

Learn more about the company Oncopeptides and the work we do to redefine cancer care

Learn more about the company Oncopeptides and the work we do to redefine cancer care

Learn more about the company Oncopeptides and the work we do to redefine cancer care

Learn more about the company Oncopeptides and the work we do to redefine cancer care