melphalan and melflufen

The objective of this article was to review existing data of melflufen (Pepaxto) as an additional treatment option for heavily pretreated relapsed and refractory multiple myeloma.. A PubMed search was completed using the search terms melphalan flufenamide; melflufen; melflufen AND relapsed refractory multiple myeloma; melphalan flufenamide and relapsed refractory multiple myeloma between January 1, 2013, and October 18, 2021. Additional information was obtained from the National Institutes of Health Clinical Trial Registry, Federal Drug Administration (FDA) web updates, and Pepaxto prescribing information.. Clinical trials including melflufen in relapsed refractory multiple myeloma and trials related to safety and clinical pharmacology were included.. The findings of this review show melflufen in combination with dexamethasone can be used as a treatment option for patients with relapsed and refractory multiple myeloma who have previously received greater than 4 previous lines of therapy, and documented resistance to a proteosome inhibitor, an anti-CD38 monoclonal antibody, and an immunomodulator.. Melflufen in combination with dexamethasone is a reasonable option for patients with relapsed and refractory multiple myeloma who have received at least 4 previous lines of therapy and considered ineligible for autologous stem cell transplant. Further clinical utilization in earlier lines of therapy is under review, pending the in-depth safety analysis by the FDA.. The FDA approval of melflufen in combination with dexamethasone provides an additional therapy option for patients with heavily pretreated relapsed and refractory multiple myeloma.

Topics: Antineoplastic Combined Chemotherapy Protocols; Dexamethasone; Humans; Melphalan; Multiple Myeloma; Peptides; Phenylalanine

Despite therapeutic advances and improved patient outcomes in recent years, multiple myeloma (MM) remains a mostly incurable hematologic malignancy. Patients with relapsed/refractory MM (RRMM), especially those with triple-class-refractory disease or poor-prognostic features, have substantially unmet needs for new therapies with novel mechanisms of action. Melphalan flufenamide (melflufen) is the first alkylating peptide-drug conjugate that targets aminopeptidases to show efficacy and manageable safety, in combination with dexamethasone, in patients with RRMM who had received at least 4 prior lines of therapy, including at least 1 immunomodulatory drug, at least 1 proteasome inhibitor and at least 1 anti-CD38 monoclonal antibody, and received accelerated approval by the U.S. Food and Drug Administration (FDA) in early 2021 for use in this patient population. Initial analyses of the phase III OCEAN study data led to melflufen being voluntarily withdrawn from the U.S. market in late 2021, but subsequent analyses have prompted the manufacturer to rescind its voluntary withdrawal to allow further discussions with the U.S. FDA and the regulatory review with the European Medicines Agency (EMA) is also ongoing. Here, we provide a review of the novel mechanism of action and pharmacokinetics of melflufen, as well as key efficacy and safety from clinical studies that supported its initial approval, and discuss the nuances of the OCEAN study data. Melflufen demonstrates the potential of novel peptide-drug conjugates to positively impact the treatment landscape in RRMM.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Humans; Melphalan; Multiple Myeloma; Phenylalanine

We review drug conjugates combining a tumor-selective moiety with a cytotoxic agent as cancer treatments. Currently, antibody-drug conjugates (ADCs) are the most common drug conjugates used clinically as cancer treatments. While providing both efficacy and favorable tolerability, ADCs have limitations due to their size and complexity. Peptides as tumor-targeting carriers in peptide-drug conjugates (PDCs) offer a number of benefits. Melphalan flufenamide (melflufen) is a highly lipophilic PDC that takes a novel approach by utilizing increased aminopeptidase activity to selectively increase the release and concentration of cytotoxic alkylating agents inside tumor cells. The only other PDC approved currently for clinical use is

Topics: Antineoplastic Agents; Cytotoxins; Drug Carriers; Drug Delivery Systems; Drug Design; Humans; Immunoconjugates; Melphalan; Neoplasms; Peptides; Pharmaceutical Preparations; Phenylalanine; Radiotherapy; Somatostatin

Despite recent therapeutic advances, multiple myeloma (MM) patients experience relapses as they become resistant to various classes and combinations of treatment. Melphalan (L-PAM) is an ageless drug. However, its use in the autologous stem cell transplantation (ASCT) setting and the innovative quadruplet regimen as well as daratumumab, bortezomib, and prednisone make this old drug current yet. Melflufen is a peptide-conjugated alkylator belonging to a novel class of compounds, representing an overcoming of L-PAM in terms of mechanism of action and effectiveness. The improved melflufen cytotoxicity is related to aminopeptidase activity, notably present in normal and neoplastic cells and remarkably heavily overexpressed in MM cells. Upon entering a cell, melflufen is cleaved by aminopeptidases, ultimately releasing the L-PAM payload and eliciting further the inflow and cleavage of the conjugated peptide. This virtuous loop persists until all extracellular melflufen has been utilized. The aminopeptidase-driven accumulation results in a 50-fold increase in L-PAM cell enrichment as compared with free alkylator. This condition produces selective cytotoxicity, increased on-target cell potency, and decreased off-target cell toxicity, ultimately overcoming resistance pathways triggered by previous treatments, including alkylators. Due to its distinct mechanism of action, melflufen plus dexamethasone as a doublet, and in combination with other novel drugs, has the potential to be beneficial for a broad range of patients with relapsed/refractory (RR) MM in third- or even in second-line therapy. The safety profile of melflufen has been consistent across studies, and no new safety concerns have been identified when melflufen was administered in doublet and triplet combinations. Based on growing clinical evidence, melflufen could be not only a good addition in the fight against RRMM but also a drug with a very favorable tolerability profile.

Topics: Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Drug Resistance, Neoplasm; Humans; Melphalan; Multiple Myeloma; Phenylalanine

The overall survival of patients with multiple myeloma has improved with the advent of novel agents; however, multiple myeloma remains incurable. Combinations of standard-of-care agents such as immunomodulators, proteasome inhibitors, and anti-CD38 monoclonal antibodies are increasingly used in earlier lines of therapy. Patients with disease that is refractory to multiple novel agents represent a population with high unmet medical need and for whom therapies with new mechanisms of action could be beneficial. Melphalan flufenamide (melflufen) has demonstrated encouraging activity in patients with relapsed and refractory multiple myeloma.. This review provides an overview of the mechanism of action of melflufen, a first-in-class peptide-drug conjugate that targets aminopeptidases and rapidly delivers alkylating agents into tumor cells. It reviews key Phase I and II clinical trial data for melflufen in combination with dexamethasone as well as in triplet combinations with daratumumab or bortezomib. The safety profile of melflufen, which is characterized primarily by clinically manageable hematologic adverse events, is described.. Melflufen has potential to fill a gap in the myeloma treatment landscape by providing a new mechanism of action with clinically meaningful efficacy and a favorable safety profile in patients refractory to multiple novel agents.

Topics: Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Humans; Melphalan; Multiple Myeloma; Phenylalanine; Recurrence; Survival Rate

Melphalan flufenamide (melflufen), an alkylating peptide-drug conjugate, plus dexamethasone showed clinical activity and manageable safety in the phase 2 HORIZON study. We aimed to determine whether melflufen plus dexamethasone would provide a progression-free survival benefit compared with pomalidomide plus dexamethasone in patients with previously treated multiple myeloma.. In this randomised, open-label, head-to-head, phase 3 study (OCEAN), adult patients (aged ≥18 years) were recruited from 108 university hospitals, specialist hospitals, and community-based centres in 21 countries across Europe, North America, and Asia. Eligible patients had an ECOG performance status of 0-2; must have had relapsed or refractory multiple myeloma, refractory to lenalidomide (within 18 months of randomisation) and to the last line of therapy; and have received two to four previous lines of therapy (including lenalidomide and a proteasome inhibitor). Patients were randomly assigned (1:1), stratified by age, number of previous lines of therapy, and International Staging System score, to either 28-day cycles of melflufen and dexamethasone (melflufen group) or pomalidomide and dexamethasone (pomalidomide group). All patients received dexamethasone 40 mg orally on days 1, 8, 15, and 22 of each cycle. In the melflufen group, patients received melflufen 40 mg intravenously over 30 min on day 1 of each cycle and in the pomalidomide group, patients received pomalidomide 4 mg orally daily on days 1 to 21 of each cycle. The primary endpoint was progression-free survival assessed by an independent review committee in the intention-to-treat (ITT) population. Safety was assessed in patients who received at least one dose of study medication. This study is registered with ClinicalTrials.gov, NCT03151811, and is ongoing.. Between June 12, 2017, and Sept 3, 2020, 246 patients were randomly assigned to the melflufen group (median age 68 years [IQR 60-72]; 107 [43%] were female) and 249 to the pomalidomide group (median age 68 years [IQR 61-72]; 109 [44%] were female). 474 patients received at least one dose of study drug (melflufen group n=228; pomalidomide group n=246; safety population). Data cutoff was Feb 3, 2021. Median progression-free survival was 6·8 months (95% CI 5·0-8·5; 165 [67%] of 246 patients had an event) in the melflufen group and 4·9 months (4·2-5·7; 190 [76%] of 249 patients had an event) in the pomalidomide group (hazard ratio [HR] 0·79, [95% CI 0·64-0·98]; p=0·032), at a median follow-up of 15·5 months (IQR 9·4-22·8) in the melflufen group and 16·3 months (10·1-23·2) in the pomalidomide group. Median overall survival was 19·8 months (95% CI 15·1-25·6) at a median follow-up of 19·8 months (IQR 12·0-25·0) in the melflufen group and 25·0 months (95% CI 18·1-31·9) in the pomalidomide group at a median follow-up of 18·6 months (IQR 11·8-23·7; HR 1·10 [95% CI 0·85-1·44]; p=0·47). The most common grade 3 or 4 treatment-emergent adverse events were thrombocytopenia (143 [63%] of 228 in the melflufen group vs 26 [11%] of 246 in the pomalidomide group), neutropenia (123 [54%] vs 102 [41%]), and anaemia (97 [43%] vs 44 [18%]). Serious treatment-emergent adverse events occurred in 95 (42%) patients in the melflufen group and 113 (46%) in the pomalidomide group, the most common of which were pneumonia (13 [6%] vs 21 [9%]), COVID-19 pneumonia (11 [5%] vs nine [4%]), and thrombocytopenia (nine [4%] vs three [1%]). 27 [12%] patients in the melflufen group and 32 [13%] in the pomalidomide group had fatal treatment-emergent adverse events. Fatal treatment-emergent adverse events were considered possibly treatment related in two patients in the melflufen group (one with acute myeloid leukaemia, one with pancytopenia and acute cardiac failure) and four patients in the pomalidomide group (two patients with pneumonia, one with myelodysplastic syndromes, one with COVID-19 pneumonia).. Melflufen plus dexamethasone showed superior progression-free survival than pomalidomide plus dexamethasone in patients with relapsed or refractory multiple myeloma.. Oncopeptides AB.

Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; COVID-19 Drug Treatment; Dexamethasone; Female; Humans; Lenalidomide; Male; Melphalan; Middle Aged; Multiple Myeloma; Phenylalanine; SARS-CoV-2; Thalidomide

Melphalan flufenamide (melflufen) is a first-in-class peptide-drug conjugate that targets aminopeptidases and rapidly and selectively releases alkylating agents into tumor cells. The phase II HORIZON trial evaluated the efficacy of melflufen plus dexamethasone in relapsed and refractory multiple myeloma (RRMM), a population with an important unmet medical need.. Patients with RRMM refractory to pomalidomide and/or an anti-CD38 monoclonal antibody received melflufen 40 mg intravenously on day 1 of each 28-day cycle plus once weekly oral dexamethasone at a dose of 40 mg (20 mg in patients older than 75 years). The primary end point was overall response rate (partial response or better) assessed by the investigator and confirmed by independent review. Secondary end points included duration of response, progression-free survival, overall survival, and safety. The primary analysis is complete with long-term follow-up ongoing.. Of 157 patients (median age 65 years; median five prior lines of therapy) enrolled and treated, 119 patients (76%) had triple-class-refractory disease, 55 (35%) had extramedullary disease, and 92 (59%) were refractory to previous alkylator therapy. The overall response rate was 29% in the all-treated population, with 26% in the triple-class-refractory population. In the all-treated population, median duration of response was 5.5 months, median progression-free survival was 4.2 months, and median overall survival was 11.6 months at a median follow-up of 14 months. Grade ≥ 3 treatment-emergent adverse events occurred in 96% of patients, most commonly neutropenia (79%), thrombocytopenia (76%), and anemia (43%). Pneumonia (10%) was the most common grade 3/4 nonhematologic event. Thrombocytopenia and bleeding (both grade 3/4 but fully reversible) occurred concomitantly in four patients. GI events, reported in 97 patients (62%), were predominantly grade 1/2 (93%); none were grade 4.. Melflufen plus dexamethasone showed clinically meaningful efficacy and a manageable safety profile in patients with heavily pretreated RRMM, including those with triple-class-refractory and extramedullary disease.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Dexamethasone; Disease Progression; Drug Resistance, Neoplasm; Europe; Female; Humans; Male; Melphalan; Middle Aged; Multiple Myeloma; Phenylalanine; Progression-Free Survival; Recurrence; Time Factors; United States

An updated survival analysis was conducted for the Phase II study O-12-M1 of melphalan flufenamide (melflufen) plus dexamethasone in patients with relapsed/refractory multiple myeloma (RRMM) with two or more prior lines of therapy (including bortezomib and lenalidomide). Partial response or better was seen in 31%. After a 46-month median overall survival (OS) follow-up, melflufen plus dexamethasone had a median OS of 20·7 months (75th percentile OS, 47·5 months). The median time-to-next treatment for melflufen plus dexamethasone was 7·9 months. In summary, melflufen plus dexamethasone resulted in sustained long-term clinical benefit in patients with RRMM.

Topics: Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Dexamethasone; Disease-Free Survival; Female; Follow-Up Studies; Humans; Male; Melphalan; Middle Aged; Multiple Myeloma; Phenylalanine; Survival Rate

Melflufen is a novel peptide-drug conjugate that rapidly delivers a cytotoxic payload into tumor cells. It has emerged as a potential new multiple myeloma treatment, particularly for late-stage forms of the disease. Here we describe the rationale and design of OCEAN (NCT03151811), a randomized, head-to-head, superiority, open-label, global, Phase III study evaluating the efficacy and safety of melflufen + dexamethasone versus pomalidomide + dexamethasone. Eligible patients with relapsed refractory multiple myeloma have received 2-4 previous treatments and are refractory to both lenalidomide and their last treatment. Patients are excluded if they have previously received pomalidomide. The primary endpoint is progression-free survival, and key secondary endpoints include overall response rate, duration of response and overall survival.

Topics: Antineoplastic Combined Chemotherapy Protocols; Clinical Trials, Phase III as Topic; Dexamethasone; Drug Resistance, Neoplasm; Humans; Lenalidomide; Melphalan; Multiple Myeloma; Phenylalanine; Progression-Free Survival; Randomized Controlled Trials as Topic; Recurrence; Thalidomide

Multiple myeloma is an incurable haematological malignancy, representing over 10% of haematological cancers in the USA. We did a phase 1-2 study of melflufen and dexamethasone in patients with relapsed and refractory multiple myeloma to determine the maximum tolerated dose of melflufen and to investigate its safety and efficacy.. We did a multicentre, international, dose-confirmation and dose-expansion, open-label, phase 1-2 study in seven centres in the USA and Europe. Eligible patients were aged 18 years or older, had relapsed and refractory multiple myeloma, had received two or more previous lines of therapy (including lenalidomide and bortezomib), were refractory to their last line of therapy, and had an Eastern Cooperative Oncology Group performance status of 2 or less. In phase 1, patients received an intravenous infusion of melflufen at 15 mg, 25 mg, 40 mg, or 55 mg for 30 min on day 1 in 21-day cycles plus oral dexamethasone 40 mg weekly and did not receive melflufen as a single agent. Melflufen was also tested in a single-agent cohort late in phase 2 in a small number of patients at the maximum tolerated dose identified in phase 1. In phase 2, patients were enrolled at the maximum tolerated dose in the melflufen plus dexamethasone in the combination cohort.. The phase 1 primary objective was to determine the maximum tolerated dose. The phase 2 primary objective was to evaluate overall response rate and clinical benefit rate. This primary analysis was done per protocol, in the all-treated and efficacy-evaluable population (defined as patients who received at least two doses of melflufen and who had a response assessment after baseline). The single-agent melflufen cohort was closed on October 6, 2016, as per the recommendation by the data safety monitoring committee on the basis of interim data suggesting greater activity in the melflufen plus dexamethasone cohort. The study is completed but survival follow-up is ongoing. This study is registered with ClinicalTrials.gov, NCT01897714.. Patients were enrolled between July 4, 2013, and Dec 31, 2016: 23 patients in phase 1 and 58 in phase 2, including six patients from phase 1 treated at the maximum tolerated dose of melflufen 40 mg plus weekly dexamethasone. In phase 2, 45 patients were given a combination of melflufen plus dexamethasone and 13 patients were given single-agent melflufen. In phase 1, the established maximum tolerated dose was 40 mg of melflufen in combination with dexamethasone. No dose-limiting toxicities were observed in the first three dose cohorts (15 mg, 25 mg, and 40 mg). The highest dose cohort tested (55 mg) exceeded the maximum tolerated dose because four of six patients experienced grade 4 neutropenia with grade 4 thrombocytopenia also occurring in three of these patients; therefore, the planned highest dose of 70 mg was not tested. In phase 2, patients treated with combination therapy achieved an overall response rate of 31% (14 of 45 patients; 95% CI 18-47) and clinical benefit rate of 49% (22 of 45; 34-64) in the all-treated population, and 41% (14 of 34; 25-59) and 65% (22 of 34; 47-80) in the efficacy-evaluable population. In the phase 2 single-agent cohort, the overall response rate was 8% (one of 13 patients; 0·2-36·0) and the clinical benefit rate was 23% (three of 13; 5-54). Among the 45 patients given melflufen plus dexamethasone during phase 2, the most common grade 3-4 adverse events were clinically manageable thrombocytopenia (28 [62%] patients) and neutropenia (26 [58%]), and non-haematological toxicity was infrequent. 24 serious adverse events were reported in 17 (38%) of 45 patients, most commonly pneumonia (five [11%]). The most common grade 3-4 adverse events that occurred in the phase 2 single-agent cohort of 13 patients were neutropenia (nine [69%]) and thrombocytopenia (eight [62%]). Nine patients experienced serious adverse events in the single-agent cohort, most commonly thrombocytopenia (two [15%]). There were three deaths from adverse events within 30 days of treatment that were possibly related to treatment: one in the 25 mg cohort in phase 1 (due to bacteraemia) and two in the phase 2 combination cohort (one due to neutropenic sepsis and one due to Escherichia coli sepsis), each in the setting of progressive disease.. These data show that melflufen is active in patients with relapsed and refractory multiple myeloma and tolerable in most patients. These results show the feasibility of this regimen and support the initiation of additional clinical studies of melflufen in multiple myeloma, both in combination with dexamethasone as well as in triplet regimens with additional classes of drugs.. Oncopeptides AB.

Topics: Aged; Antineoplastic Agents, Alkylating; Antineoplastic Agents, Hormonal; Antineoplastic Combined Chemotherapy Protocols; Dexamethasone; Disease-Free Survival; Female; Humans; Kaplan-Meier Estimate; Male; Maximum Tolerated Dose; Melphalan; Middle Aged; Multiple Myeloma; Neoplasm Recurrence, Local; Phenylalanine

Melflufen (melphalan flufenamide, previously designated J1) is an optimized and targeted derivative of melphalan, hydrolyzed by aminopeptidases overexpressed in tumor cells resulting in selective release and trapping of melphalan, and enhanced activity in preclinical models.. This was a prospective, single-armed, open-label, first-in-human, dose-finding phase I/IIa study in 45 adult patients with advanced and progressive solid tumors without standard treatment options. Most common tumor types were ovarian carcinoma (n = 20) and non-small-cell lung cancer (NSCLC, n = 11).. In the dose-escalating phase I part of the study, seven patients were treated with increasing fixed doses of melflufen (25-130 mg) Q3W. In the subsequent phase IIa part, 38 patients received in total 115 cycles of therapy at doses of 30-75 mg. No dose-limiting toxicities (DLTs) were observed at 25 and 50 mg; at higher doses DLTs were reversible neutropenias and thrombocytopenias, particularly evident in heavily pretreated patients, and the recommended phase II dose (RPTD) was set to 50 mg. Response Evaluation Criteria In Solid Tumors (RECIST) evaluation after 3 cycles of therapy (27 patients) showed partial response in one (ovarian cancer), and stable disease in 18 patients. One NSCLC patient received nine cycles of melflufen and progressed after 7 months of therapy.. In conclusion, melflufen can safely be given to cancer patients, and the toxicity profile was as expected for alkylating agents; RPTD is 50 mg Q3W. Reversible and manageable bone marrow suppression was identified as a DLT. Clinical activity is suggested in ovarian cancer, but modest activity in treatment of refractory NSCLC.

Topics: Adult; Aged; Aged, 80 and over; Alkylation; Antineoplastic Agents, Alkylating; Disease Progression; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Hematologic Diseases; Humans; Male; Melphalan; Middle Aged; Neoplasms; Peptide Hydrolases; Phenylalanine; Prospective Studies

Despite decades of development of treatments and the successful application of targeted therapies for multiple myeloma, clinical challenges remain for patients with relapsed/refractory disease. A drug designed for efficient delivery of an alkylating payload into tumor cells that yields a favorable therapeutic window can be an attractive choice. Herein we describe melphalan flufenamide (melflufen), a drug with a peptide carrier component conjugated to an alkylating payload, and its cellular metabolism. We further underline the fundamental role of enzymatic hydrolysis in the rapid and robust accumulation of alkylating metabolites in cancer cells and their importance for downstream effects. The formed alkylating metabolites were shown to cause DNA damage, both on purified DNA and on chromatin in cells, with both nuclear and mitochondrial DNA affected in the latter. Furthermore, the rapid intracellular enrichment of alkylating metabolites is shown to be essential for the rapid kinetics of the downstream intracellular effects such as DNA damage signaling and induction of apoptosis. To evaluate the importance of enzymatic hydrolysis for melflufen's efficacy, all four stereoisomers of the compound were studied in a systematic approach and shown to have a different pattern of metabolism. In comparison with melflufen, stereoisomers lacking intracellular accumulation of alkylating payloads showed cytotoxic activity only at significantly higher concentration, slower DNA damage kinetics, and different mechanisms of action to reach cellular apoptosis.

Topics: Antineoplastic Agents, Alkylating; Humans; Melphalan; Multiple Myeloma; Phenylalanine

Topics: Advisory Committees; Humans; Medical Oncology; Melphalan; Phenylalanine; United States

Melphalan flufenamide (melflufen), a first-in-class alkylating peptide-drug conjugate, plus dexamethasone demonstrated superior progression-free survival (PFS) but directionally different overall survival (OS) favoring pomalidomide (hazard ratio [HR], 1.10) in OCEAN.. These analyses further investigated prognostic subgroups impacting survival in updated data from the randomized, phase 3 OCEAN study (NCT03151811; date: February 3, 2022) and the phase 2 HORIZON study (NCT02963493; date: February 2, 2022).. In OCEAN, subgroups prognostic for OS were age (P = .011; <65 years favored pomalidomide) and no previous autologous stem cell transplant (ASCT) or progression >36 months after ASCT (P = .001; favored melflufen). Overall, 245 of 495 (49%) patients randomized had received a previous ASCT, of which 202 (82%) had progressed within 36 months following their ASCT. When excluding patients who had progressed <36 months post-ASCT (melflufen group, n = 145; pomalidomide group, n = 148), median OS was 23.6 months with melflufen and 19.8 months with pomalidomide (HR, 0.83 [95% CI, 0.62-1.12]; P = .22). Among patients with triple-class refractory disease in HORIZON, patients who had progressed <36 months post-ASCT (n = 58) had a lower response rate and shorter duration of response and PFS than the remaining patients (n = 52). Safety was consistent with previous reports.. 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).

Topics: Antineoplastic Combined Chemotherapy Protocols; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Dexamethasone; Follow-Up Studies; Humans; Melphalan; Multiple Myeloma; Randomized Controlled Trials as Topic; Risk Assessment; Transplantation, Autologous

Topics: Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Antineoplastic Agents, Alkylating; Antineoplastic Agents, Immunological; Biological Products; Clinical Trials as Topic; Drug Discovery; Humans; Lymphoma, Large B-Cell, Diffuse; Melphalan; Multiple Myeloma; Phenylalanine; Receptors, Antigen, T-Cell

Topics: Humans; Melphalan; Multiple Myeloma; Phenylalanine

Topics: Humans; Melphalan; Multiple Myeloma; Phenylalanine

Topics: Humans; Melphalan; Multiple Myeloma; Phenylalanine

Mesenchymal stem/stromal cells (MSCs) are self-renewing and multipotent progenitors, which constitute the main cellular compartment of the bone marrow stroma. Because MSCs have an important role in the pathogenesis of multiple myeloma, it is essential to know if novel drugs target MSCs. Melflufen is a novel anticancer peptide-drug conjugate compound for patients with relapsed refractory multiple myeloma. Here, we studied the cytotoxicity of melflufen, melphalan and doxorubicin in healthy human bone marrow-derived MSCs (BMSCs) and how these drugs affect BMSC proliferation. We established co-cultures of BMSCs with MM.1S myeloma cells to see if BMSCs increase or decrease the cytotoxicity of melflufen, melphalan, bortezomib and doxorubicin. We evaluated how the drugs affect BMSC differentiation into adipocytes and osteoblasts and the BMSC-supported formation of vascular networks. Our results showed that BMSCs were more sensitive to melflufen than to melphalan. The cytotoxicity of melflufen in myeloma cells was not affected by the co-culture with BMSCs, as was the case for melphalan, bortezomib and doxorubicin. Adipogenesis, osteogenesis and BMSC-mediated angiogenesis were all affected by melflufen. Melphalan and doxorubicin affected BMSC differentiation in similar ways. The effects on adipogenesis and osteogenesis were not solely because of effects on proliferation, seen from the differential expression of differentiation markers normalized by cell number. Overall, our results indicate that melflufen has a significant impact on BMSCs, which could possibly affect therapy outcome.

Topics: Bone Marrow; Bortezomib; Doxorubicin; Humans; Melphalan; Mesenchymal Stem Cells; Multiple Myeloma; Phenylalanine

Melphalan flufenamide (melflufen) is a first-in-class peptide-drug conjugate that takes advantage of increased aminopeptidase activity inside tumor cells to rapidly release alkylating agents therein. Melflufen in combination with dexamethasone has been evaluated in multiple clinical trials in patients with relapsed/refractory multiple myeloma (MM).. This profile covers the unique mechanism of action of melflufen, the preclinical results supporting its activity in cellular models of resistance to chemotherapy, its activity in animal models of MM, and the clinical pharmacokinetics of melflufen. Findings from clinical trials evaluating melflufen, including the pivotal phase II HORIZON study and the phase III OCEAN study, are discussed.. Although MM treatment has improved, patients with disease refractory to multiple standard-of-care drug classes face a dismal prognosis. Melflufen demonstrated efficacy and tolerability in select populations, with an initial approval in the United States in patients with ≥ four previous lines of therapy and triple-class-refractory MM. Results from the phase III OCEAN study - currently under discussion with regulatory agencies in the United States and Europe - are more complex and have been put into context herein. Lastly, melflufen provides a proof-of-concept for the utility of the peptide-drug conjugate platform in relapsed/refractory MM.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Dexamethasone; Europe; Melphalan; Multiple Myeloma; Phenylalanine

Topics: Animals; Antineoplastic Agents, Alkylating; Humans; Melphalan; Multiple Myeloma; Phenylalanine; Treatment Outcome

Melphalan flufenamide (hereinafter referred to as "melflufen") is a peptide-conjugated drug currently in phase 3 trials for the treatment of relapsed or refractory multiple myeloma. Due to its lipophilic nature, it readily enters cells, where it is converted to the known alkylator melphalan leading to enrichment of hydrophilic alkylator payloads. Here, we have analysed in vitro and in vivo the efficacy of melflufen on normal and cancerous breast epithelial lines. D492 is a normal-derived nontumorigenic epithelial progenitor cell line whereas D492HER2 is a tumorigenic version of D492, overexpressing the HER2 oncogene. In addition we used triple negative breast cancer cell line MDA-MB231. The tumorigenic D492HER2 and MDA-MB231 cells were more sensitive than normal-derived D492 cells when treated with melflufen. Compared to the commonly used anti-cancer drug doxorubicin, melflufen was significantly more effective in reducing cell viability in vitro while it showed comparable effects in vivo. However, melflufen was more efficient in inhibiting metastasis of MDA-MB231 cells. Melflufen induced DNA damage was confirmed by the expression of the DNA damage proteins ƴH2Ax and 53BP1. The effect of melflufen on D492HER2 was attenuated if cells were pretreated with the aminopeptidase inhibitor bestatin, which is consistent with previous reports demonstrating the importance of aminopeptidase CD13 in facilitating melflufen cleavage. Moreover, analysis of CD13

Topics: Animals; Antineoplastic Agents, Alkylating; Breast Neoplasms; CD13 Antigens; Cell Line, Tumor; Chick Embryo; Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; DNA Damage; Female; Gene Expression Regulation, Neoplastic; Histones; Humans; Leucyl Aminopeptidase; Melphalan; Phenylalanine; Signal Transduction; Tumor Suppressor p53-Binding Protein 1

The novel aminopeptidase potentiated alkylating agent melflufen, was evaluated for activity in acute myeloid leukemia in a range of in vitro models, as well as in a patient derived xenograft study. All tested AML cell lines were highly sensitive to melflufen while melphalan was considerably less potent. In the HL-60 cell line model, synergy was observed for the combination of melflufen and cytarabine, an interaction that appeared sequence dependent with increased synergy when melflufen was added before cytarabine. Also, in primary cultures of AML cells from patients melflufen was highly active, while normal PBMC cultures appeared less sensitive, indicating a 7-fold in vitro therapeutic index. Melphalan, on the other hand, was only 2-fold more potent in the AML patient samples compared with PBMCs. Melflufen was equally active against non-malignant, immature CD34+ progenitor cells and a more differentiated CD34+ derived cell population (GM14), whereas the stem cell like cells were less sensitive to melphalan. Finally, melflufen treatment showed significant anti-leukemia activity and increased survival in a patient derived xenograft of AML in mice. In conclusion, melflufen demonstrates high and significant preclinical activity in AML and further clinical evaluation seem warranted in this disease.

Topics: Animals; Antigens, CD34; Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Daunorubicin; Dose-Response Relationship, Drug; Drug Synergism; Female; HL-60 Cells; Humans; Inhibitory Concentration 50; Leukemia, Myeloid, Acute; Male; Melphalan; Mice, SCID; Middle Aged; Neoplastic Stem Cells; Phenylalanine; Time Factors; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Chemotherapy options in advanced urothelial carcinoma (UC) remain limited. Here we evaluated the peptide-based alkylating agent melphalan-flufenamide (mel-flufen) for UC.. UC cell lines J82, RT4, TCCsup and 5637 were treated with mel-flufen, alone or combined with cisplatin, gemcitabine, dasatinib or bestatin. Cell viability (MTT assay), intracellular drug accumulation (liquid chromatography) apoptosis induction (apoptotic cell nuclei morphology, western blot analysis of PARP-1/caspase-9 cleavage and Bak/Bax activation) were evaluated. Kinome alterations were characterized by PathScan array and phospho-Src validated by western blotting. Aminopeptidase N (ANPEP) expression was evaluated in UC clinical specimens in relation to patient outcome.. In J82, RT4, TCCsup and 5637 UC cells, mel-flufen amplified the intracellular loading of melphalan in part via aminopeptidase N (ANPEP), resulting in increased cytotoxicity compared to melphalan alone. Mel-flufen induced apoptosis seen as activation of Bak/Bax, cleavage of caspase-9/PARP-1 and induction of apoptotic cell nuclei morphology. Combining mel-flufen with cisplatin or gemcitabine in J82 cells resulted in additive cytotoxic effects and for gemcitabine also increased apoptosis induction. Profiling of mel-flufen-induced kinome alterations in J82 cells revealed that mel-flufen alone did not inhibit Src phosphorylation. Accordingly, the Src inhibitor dasatinib sensitized for mel-flufen cytotoxicity. Immunohistochemical analysis of the putative mel-flufen biomarker ANPEP demonstrated prominent expression levels in tumours from 82 of 83 cystectomy patients. Significantly longer median overall survival was found in patients with high ANPEP expression (P = 0.02).. Mel-flufen alone or in combination with cisplatin, gemcitabine or Src inhibition holds promise as a novel treatment for UC.

Topics: Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; bcl-2 Homologous Antagonist-Killer Protein; bcl-2-Associated X Protein; Cell Line, Tumor; Dasatinib; Humans; Melphalan; Phenylalanine; Protein Kinase Inhibitors; src-Family Kinases; Urologic Neoplasms; Urothelium

Melphalan has been used in the treatment of various hematologic malignancies for almost 60 years. Today it is part of standard therapy for multiple myeloma and also as part of myeloablative regimens in association with autologous allogenic stem cell transplantation. Melflufen (melphalan flufenamide ethyl ester, previously called J1) is an optimized derivative of melphalan providing targeted delivery of active metabolites to cells expressing aminopeptidases. The activity of melflufen has compared favorably with that of melphalan in a series of in vitro and in vivo experiments performed preferentially on different solid tumor models and multiple myeloma. Melflufen is currently being evaluated in a clinical phase I/II trial in relapsed or relapsed and refractory multiple myeloma.. Cytotoxicity of melflufen was assayed in lymphoma cell lines and in primary tumor cells with the Fluorometric Microculture Cytotoxicity Assay and cell cycle analyses was performed in two of the cell lines. Melflufen was also investigated in a xenograft model with subcutaneous lymphoma cells inoculated in mice.. Melflufen showed activity with cytotoxic IC50-values in the submicromolar range (0.011-0.92 μM) in the cell lines, corresponding to a mean of 49-fold superiority (p < 0.001) in potency vs. melphalan. In the primary cultures melflufen yielded slightly lower IC50-values (2.7 nM to 0.55 μM) and an increased ratio vs. melphalan (range 13-455, average 108, p < 0.001). Treated cell lines exhibited a clear accumulation in the G2/M-phase of the cell cycle. Melflufen also showed significant activity and no, or minimal side effects in the xenografted animals.. This study confirms previous reports of a targeting related potency superiority of melflufen compared to that of melphalan. Melflufen was active in cell lines and primary cultures of lymphoma cells, as well as in a xenograft model in mice and appears to be a candidate for further evaluation in the treatment of this group of malignant diseases.

Topics: Animals; Cell Line, Tumor; Cell Proliferation; G2 Phase Cell Cycle Checkpoints; Humans; Lymphoma; Melphalan; Mice; Multiple Myeloma; Phenylalanine; Xenograft Model Antitumor Assays

Our prior study utilized both in vitro and in vivo multiple myeloma (MM) xenograft models to show that a novel alkylator melphalan-flufenamide (Melflufen) is a more potent anti-MM agent than melphalan and overcomes conventional drug resistance. Here we examined whether this potent anti-MM activity of melflufen versus melphalan is due to their differential effect on DNA damage and repair signalling pathways via γ-H2AX/ATR/CHK1/Ku80. Melflufen-induced apoptosis was associated with dose- and time-dependent rapid phosphorylation of γ-H2AX. Melflufen induces γ-H2AX, ATR, and CHK1 as early as after 2 h exposure in both melphalan-sensitive and -resistant cells. However, melphalan induces γ-H2AX in melphalan-sensitive cells at 6 h and 24 h; no γ-H2AX induction was observed in melphalan-resistant cells even after 24 h exposure. Similar kinetics was observed for ATR and CHK1 in meflufen- versus melphalan-treated cells. DNA repair is linked to melphalan-resistance; and importantly, we found that melphalan, but not melflufen, upregulates Ku80 that repairs DNA double-strand breaks. Washout experiments showed that a brief (2 h) exposure of MM cells to melflufen is sufficient to initiate an irreversible DNA damage and cytotoxicity. Our data therefore suggest that melflufen triggers a rapid, robust, and an irreversible DNA damage which may account for its ability to overcome melphalan-resistance in MM cells.

Topics: Antineoplastic Agents, Alkylating; Apoptosis; DNA Damage; DNA Repair; Drug Resistance, Neoplasm; Histones; Humans; Kinetics; Melphalan; Multiple Myeloma; Phenylalanine; Phosphorylation; Signal Transduction; Tumor Cells, Cultured

Ovarian cancer carries a significant mortality. Since symptoms tend to be minimal, the disease is often diagnosed when peritoneal metastases are already present. The standard of care in advanced ovarian cancer consists of platinum-based chemotherapy combined with cytoreductive surgery. Unfortunately, even after optimal cytoreduction and adjuvant chemotherapy, most patients with stage III disease will develop a recurrence. Intraperitoneal administration of chemotherapy is an alternative treatment for patients with localized disease. The pharmacological and physiochemical properties of melflufen, a peptidase potentiated alkylator, raised the hypothesis that this drug could be useful in ovarian cancer and particularily against peritoneal carcinomatosis. In this study the preclinical effects of melflufen were investigated in different ovarian cancer models. Melflufen was active against ovarian cancer cell lines, primary cultures of patient-derived ovarian cancer cells, and inhibited the growth of subcutaneous A2780 ovarian cancer xenografts alone and when combined with gemcitabine or liposomal doxorubicin when administered intravenously. In addition, an intra- and subperitoneal xenograft model showed activity of intraperitoneal administered melflufen for peritoneal carcinomatosis, with minimal side effects and modest systemic exposure. In conclusion, results from this study support further investigations of melflufen for the treatment of peritoneal carcinomatosis from ovarian cancer, both for intravenous and intraperitoneal administration.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cytoreduction Surgical Procedures; Disease-Free Survival; Drug Evaluation, Preclinical; Female; Humans; Hyperthermia, Induced; Injections, Intraperitoneal; Melphalan; Mice; Mice, SCID; Neoplasm Recurrence, Local; Neoplasm Staging; Ovarian Neoplasms; Peritoneal Neoplasms; Phenylalanine; Xenograft Model Antitumor Assays

The alkylating agent melphalan prolongs survival in patients with multiple myeloma; however, it is associated with toxicities and development of drug-resistance. Here, we evaluated the efficacy of melphalan-flufenamide (mel-flufen), a novel dipeptide prodrug of melphalan in multiple myeloma.. Multiple myeloma cell lines, primary patient cells, and the human multiple myeloma xenograft animal model were used to study the antitumor activity of mel-flufen.. Low doses of mel-flufen trigger more rapid and higher intracellular concentrations of melphalan in multiple myeloma cells than are achievable by free melphalan. Cytotoxicity analysis showed significantly lower IC50 of mel-flufen than melphalan in multiple myeloma cells. Importantly, mel-flufen induces apoptosis even in melphalan- and bortezomib-resistant multiple myeloma cells. Mechanistic studies show that siRNA knockdown of aminopeptidase N, a key enzyme mediating intracellular conversion of mel-flufen to melphalan, attenuates anti-multiple myeloma activity of mel-flufen. Furthermore, mel-flufen-induced apoptosis was associated with: (i) activation of caspases and PARP cleavage; (ii) reactive oxygen species generation; (iii) mitochondrial dysfunction and release of cytochrome c; and (iv) induction of DNA damage. Moreover, mel-flufen inhibits multiple myeloma cell migration and tumor-associated angiogenesis. Human multiple myeloma xenograft studies showed a more potent inhibition of tumor growth in mice treated with mel-flufen than mice receiving equimolar doses of melphalan. Finally, combining mel-flufen with lenalidomide, bortezomib, or dexamethasone triggers synergistic anti-multiple myeloma activity.. Our preclinical study supports clinical evaluation of mel-flufen to enhance therapeutic potential of melphalan, overcome drug-resistance, and improve multiple myeloma patient outcome.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents, Alkylating; Cell Line, Tumor; Cell Movement; Cell Survival; Disease Models, Animal; Drug Synergism; Female; Humans; Melphalan; Mice; Multiple Myeloma; Neovascularization, Pathologic; Phenylalanine; Tumor Burden; Xenograft Model Antitumor Assays

Aminopeptidase N (APN) has been reported to have a functional role in tumor angiogenesis and repeatedly reported to be over-expressed in human tumors. The melphalan-derived prodrug melphalan-flufenamide (melflufen, previously designated J1) can be activated by APN. This suggests that this alkylating prodrug may exert anti-angiogenic properties, which will possibly contribute to the anti-tumoral activity in vivo. This work presents a series of experiments designed to investigate this effect of melflufen. In a cytotoxicity assay we show that bovine endothelial cells were more than 200 times more sensitive to melflufen than to melphalan, in HUVEC cells the difference was more than 30-fold and accompanied by aminopetidase-mediated accumulation of intracellular melphalan. In the chicken embryo chorioallantoic membrane (CAM) assay it is indicated that both melflufen and melphalan inhibit vessel ingrowth. Two commercially available assays with human endothelial cells co-cultured with fibroblasts (TCS Cellworks AngioKit, and Essen GFP-AngioKit) also illustrate the superior anti-angiogenic effect of melflufen compared to melphalan. Finally, in a commercially available in vivo assay in mice (Cultrex DIVAA angio-reactor assay) melflufen displayed an anti-angiogenic effect, comparable to bevacizumab. In conclusion, this study demonstrates through all methods used, that melphalan-flufenamide besides being an alkylating agent also reveals anti-angiogenic effects in different preclinical models in vitro and in vivo.

Topics: Alkylating Agents; Angiogenesis Inhibitors; Animals; Cattle; CD13 Antigens; Chick Embryo; Chorioallantoic Membrane; Drug Screening Assays, Antitumor; Human Umbilical Vein Endothelial Cells; Melphalan; Mice; Neovascularization, Pathologic; Phenylalanine; Prodrugs