Oncopeptides Reports Melflufen Uptake in Glioblastoma Tissue from Three Patients
Published in Brain/Neurology, Diseases!, Drugs development & discovery.
October 9, 2026
Oncopeptides reported preliminary findings from the INSULA study, also called OP-701, evaluating its peptide drug conjugate platform in recurrent glioblastoma. Analyses of surgically removed tumors from the first three evaluated patients detected active compound, with tissue concentrations consistent with the company’s preclinical findings.
The open-label study at Oslo University Hospital administers melflufen before surgery so investigators can measure drug distribution directly in tumor tissue. Oncopeptides interprets the findings as evidence that its delivery platform can reach human brain tumors across the blood-brain barrier.
The company reported no major drug-related toxicity so far in these patients. One participant entered an open-label extension and received five monthly doses. Postoperative weakness attributed to surgery was observed and was reportedly improving.
These are early delivery and tolerability observations from a very small group. Detecting drug in a tumor does not establish tumor control, improved survival or reliable penetration throughout a healthy brain.
INSULA is designed around tissue uptake and mechanism, rather than long-term efficacy endpoints. Melflufen’s existing European authorization should not be interpreted as approval to treat glioblastoma.