Melflufen (melphalan flufenamide)

Melflufen, a first-in-class peptide-drug conjugate, is approved in the European Union and the United Kingdom in combination with dexamethasone for the treatment of adult patients with multiple myeloma (MM) who have received at least three prior lines of therapies and 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. Melflufen is recommended in patients with no prior high-dose melphalan therapy or in those with a long treatment-free interval after such treatment (> 36 months). In high-risk patients, including patients with del(17p) and TP53 gene mutations, melflufen may be considered as a treatment option, especially if patients have not previously been treated with high-dose melphalan.

P2, N=0, Withdrawn, Fondazione EMN Italy Onlus | N=30 --> 0 | Trial completion date: Aug 2027 --> Mar 2025 | Not yet recruiting --> Withdrawn | Trial primary completion date: Feb 2027 --> Mar 2025

P2, N=30, Not yet recruiting, Fondazione EMN Italy Onlus

P3, N=495, Terminated, Oncopeptides AB | Completed --> Terminated; Sponsor assessed all endpoints and collected Overall Survival data for another two years following the primary completion date of 03Feb2021.

Finally, we observed proliferation of CD34+CD38- progenitor cells, which might be relevant for lymphocyte proliferation and function, and additionally supporting potential modulating effect. Further analyses are being done to validate these findings.

We review common toxicities associated with agents approved for RRMM in the past 5 years, including the anti-CD38 monoclonal antibody isatuximab, the antibody-drug conjugate belantamab mafodotin, the bispecific antibody teclistamab, the chimeric antigen receptor (CAR) T cell products idecabtagene vicleucel and ciltacabtagene autoleucel, the selective inhibitor of nuclear export compound selinexor, and the drug-peptide conjugate melflufen, as well as toxicities associated with emerging agents for RRMM including additional bispecific antibodies, the BCL-2 inhibitor venetoclax, and the cereblon E3 ligase modulators iberdomide and mezigdomide. We searched the published literature using PubMed, plus congress abstracts, for the above list of drug names or classes and 'myeloma.' Optimal management of toxicities associated with these recently approved and emerging therapies will be critical in maximizing clinical benefit and aiding widespread adoption in routine clinical practice. We summarize current recommendations and guidelines and provide expert insights into supportive care requirements.

Clearance increased and C decreased with increasing body weight and eGFR. In conclusion, melflufen administration differs from melphalan administration by a more rapid distribution into cells which in conjunction with a rapid intracellular metabolism allows for higher peak concentrations of alkylating agents, and by a more extensive distribution of melphalan to peripheral tissues.

The most common grade ≥3 treatment-emergent adverse events in the melflufen group versus daratumumab group were neutropenia (50% versus 12%), thrombocytopenia (50% versus 8%), and anemia (32% versus 19%). Melflufen plus daratumumab and dexamethasone demonstrated superior PFS and ORR versus daratumumab in RRMM and a safety profile comparable to previously published melflufen studies.

Notably, in the bortezomib arm, ORR was 78% and median PFS was 14.7 months. Considering the totality of the data, melflufen 30 mg was established as the recommended dose for use with dexamethasone and daratumumab or bortezomib for future studies in RRMM.

These analyses demonstrate a consistent benefit for melflufen and dexamethasone in patients with relapsed/refractory multiple myeloma who have not received an ASCT or progressed >36 months after receiving an ASCT (ClinicalTrials.gov identifier: NCT03151811).

P3, N=495, Completed, Oncopeptides AB | Active, not recruiting --> Completed | Trial completion date: Sep 2024 --> Feb 2023

From the 1960s to the early 2000s, alkylating agents (e.g., melphalan, cyclophosphamide, and bendamustine) remained a key component of standard therapy for newly-diagnosed or relapsed/refractory multiple myeloma (MM). Meanwhile, new alkylating agents (e.g., melflufen) and new applications of old alkylators (e.g., lymphodepletion before chimeric antigen receptor T-cell [CAR-T] therapy) have emerged in recent years. Given the expanding use of antigen-directed modalities (e.g., monoclonal antibodies, bispecific antibodies, and CAR-T therapy), this review explores the current and future role of alkylating agents in different treatment settings (e.g., induction, consolidation, stem cell mobilization, pre-transplant conditioning, salvage, bridging, and lymphodepleting chemotherapy) to ellucidate the role of alkylator-based regimens in modern-day MM management.