Study confirms use of Pepaxti in a broader population, with strong data in the 50% of RRMM patients that suffer from reduced kidney function

The prospective, open-label study evaluated the pharmacokinetics (PK), safety, and efficacy of Pepaxti (melflufen) plus dexamethasone in relapsed, refractory multiple myeloma (RRMM) patients with moderate-to-severe renal impairment (RI). Patients with renal insufficiency represent roughly half of all myeloma diagnoses and typically suffer from poorer long-term outcomes and limited clinical options.

"The findings are highly significant for everyday clinical practice because they demonstrate that with proper renal function-based dose adjustments, we can maintain strong disease control and survival outcomes without compromising safety or worsening kidney function in a very fragile patient segment," says Dr. Ludek Pour, Ph.D., Clinic of Internal Medicine - Hematology and Oncology, University Hospital Brno, Czech Republic, and lead author of the study.

The final analyses demonstrate that while systemic exposure to the active metabolite melphalan varies based on baseline kidney function, a reduced melflufen starting dose of 30 mg in patients with moderate renal impairment delivers a consistent safety profile, treatment responses, and survival measures aligned with prior trials conducted in less selected populations.

Furthermore, exploratory data gathered across the treatment cycles showed that renal function remained stable or slightly improved during therapy, suggesting that Pepaxti does not adversely impact the kidneys at the studied doses.

Key study highlights:

• Validated dose optimization: The PK data directly validate the clinical use and efficacy of a 30 mg Pepaxti starting dose for patients with moderate renal impairment (eGFR ≤30 to <45 mL/min/1.73 m²).
• Sustained efficacy in fragile populations: Patients with moderate renal impairment achieved an Overall Response Rate (ORR) of 47.6% in Cohort 1a (40 mg starting dose) and 70.0% in Cohort 1b (30 mg starting dose), with a median progression-free survival (PFS) of 8.6 months and 7.7 months, respectively.
• No new safety signals: Despite advanced renal impairment and high treatment exposure, the safety profile was well-characterized and manageable. The most frequently reported treatment-emergent adverse events were hematological (thrombocytopenia, anemia, and neutropenia), which is consistent with previous clinical trials.

"This publication adds critical scientific peer-reviewed validation to the treatment algorithm of Pepaxti, specifically strengthening our data footprint in patient subgroups with renal impairment," says Stefan Norin, Chief Medical Officer at Oncopeptides. "By demonstrating that Pepaxti can be safely administered at an optimized 30 mg dose, BRIDGE gives healthcare professionals the clinical confidence they need to confidently utilize this therapy in a broader patient population."

The full article, titled "BRIDGE (OP-107): A Phase 2 Pharmacokinetic Study of Melflufen Plus Dexamethasone in Patients with Relapsed/Refractory Multiple Myeloma and Impaired Renal Function," is available online via Clinical Lymphoma, Myeloma and Leukemia.

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