ALLG MM23: This phase III trial is comparing the use of an oral cancer drug (Lenalidomide) alone and in combination with chemotherapy (Selinexor) and a corticosteroid (Dexamethasone) in patients with newly diagnosed multiple myeloma who are currently undergoing Autologous stem cell transplantAn ALLG phase 3 randomised trial of Selinexor and Lenalidomide-dexamethasone versus lenalidomide maintenance post Autologous stem cell transplant for patients with Newly Diagnosed multiple myeloma

Inclusion

• Patient must be 18 years of age or older
• Patient has voluntarily agreed and has given written consent to both the main study and
correlative study
• Diagnosis of MM as per IMWG guidelines (Appendix 3)
• Must be eligible for front-line melphalan conditioned ASCT
• Will have undergone at least 3-6 cycles of up-front therapy containing a proteasome
inhibitor (PI) and/or immunomodulatory drug (IMID) and ASCT (tandem transplants
allowable) prior to screening procedures (note consent and registration will occur prior to
ASCT
• Pre-ASCT (preferably prior to and if not, as early as possible during induction therapy)
bone marrow aspirate trephine for correlative studies. Patients who are unable to provide
pre ASCT BMAT samples for correlative studies can be enrolled into the study if a waiver
is granted from the coordinating principal investigator
• Measurable disease at diagnosis:
• Serum M-protein greater than or equal to 5 g/L, or
• Urine M-protein greater than or equal to 200 mg/24 hour, or
• In patients without measurable serum or M-protein, serum free light chain (SFLC)
greater than 100mg/L (involved light chain) and an abnormal serum k/l ratio or
• In IgA patients whose disease can only be reliably measured by serum quantitative
immunoglobulin (qIgA) greater than or equal to 7500 mg/L (7.5 g/L).
• Female patients who are postmenopausal for at least 1 year prior to screening visit OR
surgically sterile OR agree to practice 2 effective methods of contraception at the same
time from 4 weeks before start of study treatment and until 90 days after the last dose of
study drugs OR agree to practice true abstinence when this is in line with the preferred
and usual lifestyle of the subject.
• Male patients, even if surgically sterilized (i.e., status post-vasectomy), must agree to
practice effective barrier contraception during the entire study treatment period and
through 90 days after the last dose of study drug, OR to practice true abstinence when
this is in line with the preferred and usual lifestyle of the subject.
• Eastern Cooperative Oncology Group (ECOG) performance status 0, 1, or 2 (Appendix 2).
• Subjects must agree not to donate blood, semen or sperm while on study and at least 90
days after treatment discontinuation.
• Subjects must agree not to share their medication and to return unused supplies.
• Patients must meet the following clinical laboratory criteria:
o Absolute neutrophil count (ANC) greater than or equal to 1.5x10^9/L and platelet count
greater than or equal to 100 x10^9/L. Platelet transfusions to help patients meet
eligibility criteria are not allowed.
o Total bilirubin less than or equal to 1.5 x the upper limit of the normal range (ULN)
o Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) less than or equal
to 3 x ULN.
o Calculated creatinine clearance greater than or equal to 30 mL/min per Cockcroft-Gault
equation.