This is a Phase 2, double-blind, randomized placebo-controlled trial in patients with higher-risk monoclonal gammopathy of undetermined significance (MGUS) and low-risk smoldering multiple myeloma (SMM) to test the efficacy of metformin in reducing clinical indicators of disease progression in MGUS and SMM patients.~Metformin is considered investigational, which means it has not been approved for the study of cancer prevention by the United States Food and Drug Administration. It has been approved for other uses including for blood sugar control in some people with Type II diabetes.~Multiple myeloma is a cancer of the plasma cells, which is an important part of the immune system. Patients with active multiple myeloma generally require treatment. There are currently no approved therapies for MGUS and SMM patients.~Metformin is a medication that is commonly used in the treatment of diabetes. Metformin works by decreasing glucose production in the liver, decreasing glucose absorption, and improving insulin sensitivity. This study is interested in studying this medication because several recent studies indicate that the drug may help prevent progression in patients with MGUS or SMM. This study is looking to learn more about whether metformin will benefit patients with MGUS or SMM who may not have diabetes.~The research study procedures include screening for eligibility and study treatment including evaluations and follow up visits.~After enrollment participants will be randomized assigned to receive either the Placebo or Metformin pills and to take them for 6 months depending on participant tolerance to the drug.~Participants will have the option to learn their treatment assignment after primary (6-month) outcome assessments are complete, and individuals randomized to metformin will have the opportunity to continue to take metformin for an additional 6-months to allow for the observation of potentially longer-term treatment response. Participants who choose to be unblinded and are taking placebo will discontinue study medication.~It is expected that about 80 people will take part in this research study.~The National Cancer Institute of the National Institutes of Health is supporting this trial.
The purpose of this research is to understand whether the drug metformin could be used in the future to help prevent patients with monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) from developing multiple myeloma.~The names of the study drug involved in this study is:~Metformin, extended release~Placebo ( a pill that has no active ingredients)