Physicians at UCLA are recruiting participants for several studies of drugs to treat disorders and cancers of the blood and bone marrow.
Myelofibrosis study
A new clinical trial will study a drug that blocks the activity of a gene that has mutated in 50 percent of patients with myelofibrosis. In myelofibrosis, one of a class of diseases called myeloproliferative disorders, the bone marrow develops excessive scarring. The scarring prevents blood-forming cells from residing in the bone marrow and they often move instead to the spleen, which becomes progressively enlarged. Myelofibrosis is a rare condition that primarily affects people in their late 50s or early 60s. Symptoms include fatigue and abdominal pain.
Physicians do not know what causes myelofibrosis, and there is no standard treatment that is effective. The few options available, including blood transfusions and medications such as Interferon, have limited success.
Researchers believe that the mutation of the JAK2 gene contributes to bone marrow changes that occur in myelofibrosis. UCLA’s randomized, double-blind, placebo-controlled Phase 3 clinical trial will study the efficacy of a drug known as INCB018424, which inhibits the activity of the abnormal JAK2 gene.
In earlier clinical trials, the drug was able to markedly reduce the size of the spleen and improve the symptoms of myelofibrosis in a majority of the participants.
To be included in UCLA’s study, myelofibrosis patients must have an enlarged spleen among other criteria.
Myelodysplastic syndrome studies
Two clinical trials at UCLA focus on treatments for myelodysplastic syndrome, a group of disorders in which the bone marrow underproduces blood cells. Myelodysplasia increases patients’ risk of developing acute myeloid leukemia. Anemia is the most common blood abnormality seen in myelodysplasia patients, and some have low platelet counts that may necessitate transfusions. Other symptoms include shortness of breath, bruising and dizziness. Myelodysplasia is rare, but less so than myelofibrosis. It generally affects people in their 70s, men more than women.
Drug combination shows promise
One UCLA study focuses on patients with advanced myelodysplasia who are at higher risk of developing acute myeloid leukemia. The Phase 2 clinical trial examines the safety and efficacy of combining two Food and Drug Administration-approved drugs, Revlimid (lenalidomide) and Vidaza (azacitidine), for the treatment of high-risk myelodysplasia.
Earlier trials found the complete remission rates for the drug combination exceeded 40 percent. Complete remission rates with only Vidaza, which is a standard treatment for high-risk patients, are typically less than 20 percent. Rates for just Revlimid, which is approved for lower-risk myelodysplasia, would not be expected to be high.
Participants in this study must have advanced myelodysplasia with increased numbers of acute leukemia-like cells in their bone marrow. They must not have been previously exposed to either Revlimid or Vidaza.
Platelet drug examined
Another trial centers on lower-risk myelodysplasia. While growth factors such as Procrit and Neupogen can help stimulate bone marrow to produce more red blood cells and white blood cells, respectively, there is no approved drug that helps patients make platelets. Blood transfusion, which typically is not effective for long periods, has been the only treatment option.
UCLA’s trial is studying the safety and efficacy of AMG 531 — a platelet growth factor recently approved for the platelet-depleting disorder immune thrombocytopenic purpura — for low-risk myelodysplasia patients who have severely low platelet counts. Researchers have found it challenging to recruit participants for this study because it’s unusual for patients with early or lower-risk myelodysplasia (those without increased bone marrow leukemic-type cells) to have severely low platelet counts. The study is being conducted as a randomized, double-blind, placebo-controlled clinical trial.