Earlier this year, President Barak Obama called for increased investment in treatments and tools that help doctors tailor medical care for individual patients. The goal is to usher in a new era of precision medicine where everyone receives customized care that takes into account their individual genetic makeup, environment, and lifestyle. This individualized approach promises to be more effective and cause fewer side effects than the current “one-size-fits-all” approach to treatment.
Cancer is one area where precision medicine has started to deliver on its promise. There are a number of targeted therapies available that specifically target genes or proteins that contribute to cancer growth and survival. Today, researchers at the 2015 ASCO Annual Meeting announced results showing how targeted therapies can be used to improve the care of people with a number of different types of blood cancer.
Chronic Lymphocytic Leukemia
In a large, ongoing study, researchers found that combining the targeted therapy ibrutinib (Imbruvica) with standard treatment slows the growth of chronic lymphocytic leukemia (CLL) and lowers a person’s risk of dying from the disease. The standard treatment for CLL is usually a combination of bendamustine (Treanda) and rituximab (Rituxan). After about a year and a half, the people who received ibrutinib were 80% less likely to have the disease worsen or die from the disease. In addition, the people receiving ibrutinib experienced less CLL-related fatigue.
In another ongoing study, researchers found that combining a new targeted therapy called obinutuzumab (Gazyva) with chemotherapy helped control the growth of non-Hodgkin lymphoma (NHL) for more than twice as long as chemotherapy alone (about 29 months compared with 14 months). All of the people who participated in this study had indolent, or slow-growing, NHL.
According to the results of a recent small study, the targeted drug daratumumab may work well after other treatments for multiple myeloma have not worked. The researchers found that after about nine months, daratumumab slowed the cancer’s growth for 29% of patients. In addition, three people had a complete remission, which means that they had no signs of the cancer.
“The efficacy we’re seeing is quite impressive for a clinical trial of multiple myeloma, given that many patients had already undergone five or more types of treatment,” said lead study author Saad Zafar Usmani, MD, a hematologist at Levine Cancer Institute/Carolinas Healthcare System in Charlotte, NC. “Our hope is that daratumumab will help fill the unmet need of patients who have exhausted available treatment approaches.”
The final study announced today suggests that the new targeted therapy pacritinib works better for myelofibrosis than current treatments. Myelofibrosis is a rare blood cancer that develops when the bone marrow is unable to make enough blood cells. As a result, the spleen takes over making blood cells and becomes quite enlarged.
Six months after treatment, about 19% of people who received pacritinib had their spleens shrink, compared with almost 5% receiving other treatments. In addition, people receiving pacritinib had less weight loss, night sweats, fever, and bone pain. Pacritinib also increased red blood cell levels, helping about 26% of the study participants avoid regular red blood cell transfusions.
Benefiting from research
“We’ve made tremendous progress against many forms of blood cancer, but there are still patients with few to no treatment options,” said ASCO expert Charles J. Ryan, MD. “By exploiting cancer’s genetic vulnerabilities, we’re finally in a position to help keep the disease at bay for these patients and ease some of their most difficult symptoms.”
Researchers continue to look for new targets and develop treatments directed at them in the hopes of realizing the potential of precision medicine and improving the lives of people with all types of cancer.