Title

Study of Melflufen (Melphalan Flufenamide) in Combination With Daratumumab in Relapsed-Refractory Multiple Myeloma
A Randomized, Controlled, Open-Label Phase 3 Study of Melflufen in Combination With Daratumumab Compared With Daratumumab in Patients With Relapsed or Relapsed-Refractory Multiple Myeloma
  • Phase

    Phase 3
  • Study Type

    Interventional
  • Indication/Condition

    Multiple Myeloma ...
  • Study Participants

    54
This was a randomized, controlled, open-label, Phase 3 multicenter study which enrolled patients with Relapsed-Refractory Multiple Myeloma (RRMM) who were either double refractory to an Immunomodulatory Drug (IMiD) and a Proteasome Inhibitor (PI) (regardless of the number of prior lines of therapy), or had received at least 3 prior lines of therapy including an IMiD and a PI.

Patients received treatment with melflufen+dexamethasone+daratumumab or daratumumab until documented progressive disease, unacceptable toxicity, or patient/treating physician decision. Patients in the daratumumab treatment arm had the option to receive treatment with melflufen+dexamethasone+daratumumab after confirmed progressive disease.
Study Started
Dec 21
2020
Primary Completion
Feb 07
2022
Study Completion
Feb 07
2022
Results Posted
Jun 08
2023
Last Update
Jun 08
2023

Drug Melflufen

Powder for solution for i.v. infusion

  • Other names: Melphalan Flufenamide, Pepaxto, Pepaxti

Drug Dexamethasone

Oral tablets

  • Other names: Dex

Drug Daratumumab

Solution for s.c. injection

  • Other names: Darzalex FASPRO

Arm A (melflufen+dexamethasone+daratumumab) Experimental

Treatment was given in 28-day cycles in an outpatient treatment setting. Melflufen 30 mg intravenous (i.v.) infusion on Day 1 of each cycle Dexamethasone 40 mg per oral (p.o.) weekly (20 mg p.o. weekly if ≥75 years) Daratumumab 1800 mg subcutaneously (s.c.) on Days 1, 8, 15, and 22 in Cycles 1 and 2, on Days 1 and 15 in Cycles 3 to 6, and on Day 1 from Cycle 7

Arm B (daratumumab) Active Comparator

Treatment was given in 28-day cycles in an outpatient treatment setting. • Daratumumab 1800 mg s.c. on Days 1, 8, 15, and 22 in Cycles 1 and 2, on Days 1 and 15 in Cycles 3 to 6, and on Day 1 from Cycle 7

Criteria

Inclusion Criteria:

A prior diagnosis of multiple myeloma with documented disease progression after the last line of therapy
Double refractory to an IMiD and a PI (regardless of the number of prior lines of therapy) or have received at least 3 prior lines of therapy including an IMiD and a PI

Prior treatment with daratumumab or another anti-CD38 antibody may be allowed under certain circumstances:

Achieved at least partial response (PR) and not refractory to an anti-CD38 antibody
At least 6 months since the last dose of anti-CD38 antibody
Not discontinued anti-CD38 antibody treatment due to related Grade ≥ 3 toxicity
Male and female of childbearing potential agree to use contraception during the treatment period and at least 3 months after the last dose

Exclusion Criteria:

Primary refractory disease (i.e., never responded with at least Minimal Response to any prior therapy for multiple myeloma)
Prior treatment with CD38 CAR-T cell therapy or CD38/CD3 bispecific antibodies
Any medical condition that may interfere with safety or participation in this study
Other malignancy diagnosed or requiring treatment within the past 3 years with the exception of adequately treated basal cell carcinoma, squamous cell skin cancer, carcinoma in-situ of the cervix or breast, or very low and low-risk prostate cancer in active surveillance
Known or suspected amyloidosis, plasma cell leukemia, or POEMS syndrome (plasma cell dyscrasia with polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes)
Known central nervous system (CNS) or meningeal involvement of myeloma
Prior stem cell transplant (autologous and/or allogenic) within 6 months of initiation of therapy or prior allogeneic stem cell transplantation with active graft-versus-host-disease
Prior treatment with melflufen

Summary

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Crossover (From Arm B to the Same Treatment as Arm A)

All Events

Event Type Organ System Event Term Arm A (Melflufen+Dexamethasone+Daratumumab) Arm B (Daratumumab) Crossover (From Arm B to the Same Treatment as Arm A)

Progression Free Survival (PFS)

Time from the date of randomization to the date of first documentation of confirmed progressive disease (PD) or death due to any cause, whichever occurred first.

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

4.86
months (Median)
95% Confidence Interval: 3.38

Overall Response Rate (ORR)

Proportion of patients who achieve a best-confirmed response of stringent Complete Response (sCR), Complete Response (CR), Very Good Partial Response (VGPR), or Partial Response (PR).

Arm A (Melflufen+Dexamethasone+Daratumumab)

59.3
percentage of patients
95% Confidence Interval: 38.8 to 77.6

Arm B (Daratumumab)

29.6
percentage of patients
95% Confidence Interval: 13.8 to 50.2

Duration of Response (DOR)

Time from the first evidence of confirmed assessment of sCR, CR, VGPR or PR to first confirmed disease progression, or death due to any cause. DOR is defined only for patients with a confirmed PR or better.

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Best Response

Proportion of patients with sCR, CR, VGPR, PR, Minimal Response (MR), Stable Disease (SD), PD, or non-evaluable (NE).

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Clinical Benefit Rate (CBR)

The proportion of patients who achieve a best confirmed response of sCR, CR, VGPR, PR, or MR.

Arm A (Melflufen+Dexamethasone+Daratumumab)

70.4
percentage of patients
95% Confidence Interval: 49.8 to 86.2

Arm B (Daratumumab)

48.1
percentage of patients
95% Confidence Interval: 28.7 to 68.1

Duration of Clinical Benefit (DOCB)

Time from first evidence of confirmed assessment of sCR, CR, VGPR, PR, or MR to first confirmed disease progression, or to death due to any cause. DOCB is defined only for patients with a confirmed MR or better.

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Time to Response (TTR)

Time from randomization to the date of the first documented confirmed response in a patient who has responded with ≥PR.

Arm A (Melflufen+Dexamethasone+Daratumumab)

1.8
months (Mean)
Standard Deviation: 1.0

Arm B (Daratumumab)

1.8
months (Mean)
Standard Deviation: 1.1

Time to Progression (TTP)

Time from randomization to the date of the first documented confirmed PD

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Time to Next Treatment (TTNT)

Time from randomization to the date of next anti-myeloma treatment or until death.

Arm A (Melflufen+Dexamethasone+Daratumumab)

11.04
months (Median)
95% Confidence Interval: None

Arm B (Daratumumab)

Overall Survival (OS)

Time from randomization to death due to any cause.

Arm A (Melflufen+Dexamethasone+Daratumumab)

11.04
months (Median)
95% Confidence Interval: None

Arm B (Daratumumab)

Total

54
Participants

Age, Continuous

65.6
years (Mean)
Full Range: 43.0 to 83.0

Height

168.7
cm (Mean)
Full Range: 150.0 to 195.0

Weight

79.1
kg (Mean)
Full Range: 56.3 to 107.6

Age, Customized

Eastern Cooperative Oncology Group (ECOG) score

Ethnicity (NIH/OMB)

Race (NIH/OMB)

Sex: Female, Male

Arm A/Arm B Treatment

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)

Crossover (Arm B)

Arm B (Daratumumab)

Drop/Withdrawal Reasons

Arm A (Melflufen+Dexamethasone+Daratumumab)

Arm B (Daratumumab)