Oncopeptides – European Journal of Haematology: Real-World Data reinforces Pepaxti’s role in treatment sequencing for multiple myeloma
Stockholm – March 13, 2026 – Oncopeptides AB (publ) (Nasdaq Stockholm: ONCO), a biotech company focused on difficult-to-treat cancers, today announces the publication of a new real-world study in the peer-reviewed European Journal of Haematology. The study, conducted at the IRCCS Azienda Ospedaliero-Universitaria di Bologna, Italy, confirms the efficacy and safety of Pepaxti (melflufen) plus dexamethasone. The heavily pretreated patients, including those refractory to novel immunotherapies, benefitted from Pepaxti’s strong efficacy, the overall response rate (ORR) was 41% with a median progression-free survival (mPFS) of 9.0 months.
The retrospective analysis evaluated 17 patients with relapsed/refractory multiple myeloma (RRMM) treated in a real-world setting outside of clinical trials. Despite a highly refractory population—where 88% were triple-class refractory and 41% were penta-drug refractory—Pepaxti demonstrated a clinically meaningful overall response rate (ORR) of 41%.
Key Study Highlights:
- Strong efficacy in late-line settings: The ORR was 41%, with a median progression-free survival (mPFS) of 9.0 months in responding patients.
- Preserved access to future therapies: Notably, 100% of patients who received subsequent novel immunotherapies (such as CAR-T or bispecific antibodies) after Pepaxti achieved a partial response or better, with the majority reaching a very good partial response (VGPR) or better.
- Manageable safety in frail populations: The safety profile was consistent with previous clinical trials, despite a high portion (41%) of the cohort being >75 years old and many presented with reduced renal function.
- Strategic positioning: The data suggests Pepaxti serves as an effective “bridging” or interval therapy, maintaining disease control without compromising the success of subsequent T-cell redirecting treatments.
“Collectively, our data confirmed the efficacy previously reported with melflufen–dexamethasone and its manageable safety profile, also in elderly patients that likely are more fragile and more heavily pretreated than those included in the trials,” says Dr. Elena Zamagni, Associate Professor at the University of Bologna, Italy, and lead author of the study. “Melflufen–dexamethasone may represent a treatment option, especially for patients refractory to novel immunotherapies or those who are not ideal candidates to receive such treatments while still preserving access to subsequent T-cell redirecting therapies”.
“This independent real-world evidence from a leading European center is highly encouraging as we continue the commercial roll-out of Pepaxti in Italy and across Europe,” says Stefan Norin, Chief Medical Officer at Oncopeptides. “The 100% response rate observed in subsequent immunotherapies is particularly significant for clinicians, as it addresses the critical question of treatment sequencing and confirms that Pepaxti can be used effectively to bridge patients to the next generation of care”.
The full article, titled “Positioning of Melflufen in Heavily Pretreated RRMM Patients: Real-World Evidence in a Rapidly Evolving Therapeutic Landscape,” is available online through this link.
For more information, including a Q&A for investors, please visit www.oncopeptides.com.
For more information, please contact:
David Augustsson, Director of IR and Communications, Oncopeptides AB (publ)
E-mail: ir@oncopeptides.com
Cell phone: +46 76 229 38 68
About Oncopeptides
Oncopeptides is a Swedish biotech company focusing on research, development and commercialization of targeted therapies for difficult-to-treat cancers.
The company uses its proprietary Peptide Drug Conjugate platform (PDC) to develop compounds that rapidly and selectively deliver cytotoxic agents into cancer cells. Its flagship drug is currently being commercialized in Europe with partnership agreements for South Korea, the Middle East and Africa and elsewhere.
Oncopeptides is also developing several new compounds based on its two proprietary technology platforms PDC and SPiKE.
The company was founded in 2000, has about 80 employees with operations in Sweden, Germany, Austria, Spain and Italy. Oncopeptides is listed on Nasdaq Stockholm with the ticker ONCO.
For more information see: www.oncopeptides.com
About Pepaxti
Pepaxti® (melphalan flufenamide, also called melflufen) has been granted Marketing Authorization, in the European Union, the EEA-countries Iceland, Lichtenstein and Norway, as well as in the UK. Pepaxti is indicated in combination with dexamethasone for the treatment of adult patients with multiple myeloma who have received at least three prior lines of therapies, whose disease is refractory to at least one proteasome inhibitor, one immunomodulatory agent, and one anti-CD38 monoclonal antibody, and who have demonstrated disease progression on or after the last therapy. For patients with a prior autologous stem cell transplantation, the time to progression should be at least 3 years from transplantation.
