Oncopeptides Reports Promising Initial Results in Glioblastoma Study, Confirming Blood-Brain Barrier Penetration

Oncopeptides AB has reported encouraging preliminary data from its Window-of-Opportunity study, showcasing the ability of its Peptide Drug Conjugate platform to successfully penetrate the blood-brain barrier in glioblastoma patients, a significant advancement in the treatment of this aggressive cancer.

Oncopeptides AB (publ), a biotechnology company dedicated to developing therapies for challenging cancers, has announced results from the first three patients enrolled in its ongoing Window-of-Opportunity (WoO) study, OP-701 (INSULA). This clinical trial investigates the efficacy of the company’s proprietary Peptide Drug Conjugate (PDC) platform in targeting glioblastoma, a particularly aggressive form of brain cancer. The findings reveal successful penetration of the human blood-brain barrier (BBB), a crucial obstacle in neuro-oncology, and confirm intra-tumoral drug concentrations that align closely with preclinical models, alongside a good safety profile.

The blood-brain barrier serves as a protective shield that limits the entry of therapeutic agents into the central nervous system. Over 90 percent of traditional systemic cancer drugs fail in their attempt to effectively reach brain tissues, making this barrier one of the most formidable challenges in treating brain cancers. The ability to demonstrate significant BBB penetration and effective delivery of a cytotoxic payload into glioblastoma cells marks a pivotal moment in advancing the clinical proof-of-concept for Oncopeptides’ PDC platform.

Significance of the Findings

Sofia Heigis, CEO of Oncopeptides, commented on the study’s implications, stating, “Reaching our primary objective to confirm that our PDC technology successfully crosses the human blood-brain barrier is a major breakthrough for Oncopeptides.” Heigis highlighted that for decades, the BBB has obstructed effective treatments for glioblastoma patients. “Demonstrating meaningful drug penetration in resected brain tumors in patients after a single dose validates the fundamental strength and versatility of our platform,” she noted, suggesting that this advancement transforms the company’s brain cancer initiative from a theoretical scientific premise into a clinically justified opportunity.

The INSULA study is being conducted at Oslo University Hospital in Norway and employs melflufen, a drug approved by the European Medicines Agency (EMA), as part of Oncopeptides’ PDC platform. This trial specifically targets patients scheduled for surgical intervention due to recurrent glioblastoma, allowing the researchers to measure drug uptake and cytotoxic activity directly in resected tumor tissue, thus providing valuable insights into the drug’s performance in a clinical setting.

Key Highlights from the Initial Patient Data

The preliminary data from the first three patients involved in the study yielded several notable highlights:

• Confirmed BBB Penetration: Analysis of resected tumor tissue from the evaluated patients revealed a clear and consistent presence of the active compound, which serves as the primary endpoint for this segment of the study. This confirms efficient penetration across the BBB.
• Safety and Tolerability: The treatment has demonstrated good tolerability among the patients evaluated thus far, with no significant drug-related toxicity reported. The first patient has continued into the open-label extension of the study, having received five monthly doses without the emergence of new tumor-related neurological symptoms, although some postoperative paresis has been observed, which is currently improving under ongoing treatment.
• Drug Concentrations: Intra-tumoral drug concentrations within the brains of the three patients were consistent with data derived from preclinical studies, affirming the effectiveness of the PDC platform.
• Surgical Outcomes: There were no unexpected surgical complications reported during the procedures associated with the study.

Professor Petter Brandal, MD, PhD, affiliated with Oslo University Hospital and the primary investigator of the WoO study, emphasized the importance of these findings, stating, “Crossing the blood-brain barrier in patients diagnosed with glioblastoma is an important step for any systemic brain cancer therapy. These initial tissue findings demonstrate that Oncopeptides’ lipophilic PDC molecules behave in human tumors just as anticipated, delivering significant concentrations in tumor cells where standard treatments historically fall short.”

Future Directions in Research

The INSULA study continues to recruit patients, aiming to ultimately include around ten participants to further characterize the pharmacokinetics and pharmacodynamics of the treatment. The positive data obtained from the first three patients will serve as both a biological and clinical foundation to guide further development in the study and the future advancement of next-generation PDC assets.

Glioblastoma represents the most aggressive and common form of primary brain cancer, characterized by a dismal median overall survival rate of just 12 to 15 months, with limited effective treatment options currently available. The global market for glioblastoma reflects a critical unmet medical need, underscoring the urgency for innovative therapeutic approaches that can improve patient outcomes in this challenging landscape.