This clinical trial will study ruxolitinib-based treatment of acute graft-versus-host-disease (GVHD) that developed following allogeneic hematopoietic cell transplant. Acute GVHD occurs when donor cells attack the healthy tissue of the body. The most common symptoms are skin rash, jaundice, nausea, vomiting, and/or diarrhea. The standard treatment for GVHD is high dose steroids such as prednisone or methylprednisolone, which suppresses the donor cells, but sometimes there can be either no response or the response does not last. In these cases, the GVHD can become dangerous or even life threatening. High dose steroid treatment can also cause serious complications. Researchers have developed a system, called the Minnesota risk system, to help predict how well the GVHD will respond to steroids based on the symptoms present at the time of diagnosis. The Minnesota risk system classifies patients with newly diagnosed acute GVHD into two groups with highly different responses to standard steroid treatment and long-term outcomes. This protocol maximizes efficiency because all patients with grade II-IV GVHD are eligible for screening and treatment is assigned according to patient risk. Patients with lower risk GVHD, Minnesota standard risk, have high response rates to steroid treatment. In this trial the researchers will test whether ruxolitinib alone is as effective (non-inferior) as steroid-free therapy and safe. Patients will be randomized to two different doses of ruxolitinib to identify the dose which maximizes efficacy while minimizing toxicities such as hematologic and infectious toxicities. Patients with higher risk GVHD, Minnesota high risk, have unacceptable outcomes with systemic corticosteroid treatment alone and the researchers will test whether adding ruxolitinib, a proven effective second line GVHD treatment, can improve outcomes when added to systemic corticosteroids as first line treatment.

Study ASTX030-01 is a multi-phase study comprising of Phases 1-3 Monotherapy arms, and Phase 1 and Phase 2 Combination Therapy arms. Phase 1 Monotherapy consists of an open-label Dose Escalation Stage (Stage A) using multiple cohorts at escalating dose levels of oral cedazuridine and azacitidine (only one study drug will be escalated at a time) followed by a Dose Expansion Stage (Stage B). Phase 2 Monotherapy is a randomized, open-label, crossover study to compare oral ASTX030 to subcutaneous (SC) azacitidine. Phase 3 Monotherapy is a randomized open-label crossover study comparing the final fixed dose of oral ASTX030 to SC azacitidine. Phase 1 Combination Therapy is an open-label, multicenter, randomized, exploratory study comparing ASTX030 and SC azacitidine in combination with venetoclax in participants with treatment-nave AML. Phase 2 Combination Therapy is an open-label, single arm, study evaluating the efficacy, safety, pharmacokinetics (PK), and drug interactions of ASTX030 in combination with venetoclax in participants with treatment-nave AML.

The duration of this multi-phase study is approximately 8 years.

The main aim of this study is to find out how well elritercept works in lowering the need for RBC transfusions. Other aims are to learn how well elritercept works in reducing the need for RBC transfusions over longer periods of time or in adults with high transfusion needs. The study will also check on how safe elritercept is and how well it is tolerated.