Participants in this study will receive 4 weekly infusions of the study drug, isatuximab, by intravenous infusion. The dose of isatuximab infusions may be larger or smaller and take a longer or shorter time to infuse depending on your weight and time required will decrease from the first to second infusion and from the second to third and fourth infusion. Participants will be observed for 2 hours after each infusion. Participants will continue to receive platelet transfusions according to standard clinical care and will be followed for about 120 days after their last dose of isatuximab.
Some of the treatments for cancer can cause platelets (the part of the blood that helps with clotting) to decrease. If they are too low, then clinicians may recommend a transfusion (getting platelets from another person added to someone else's body). This usually works to increase the person's platelets to a healthy level, but sometimes it doesn't work. This is called platelet refractoriness. This study is trying to find out whether isatuximab (the study drug) may help people with a certain type of platelet refractoriness by removing some cells in order to make platelet transfusions more effective.