Clinical trials are the gold-standard tool for driving evidence-based medical research today. With the benefits they can present to patients, trials should be considered a viable healthcare option, particularly in oncology. Cancer trials can potentially reduce treatment cost burdens for patients and advance our grasp of how cancer develops. In this next installment of Vial CRO’s Oncology Trial Management series, we discuss how sponsors can increase their chances of success when running a leukemia clinical trial.
1 | Understanding Leukemia
Leukemia is a broad diagnosis for when cancer takes hold of blood stem cells in the bone marrow. Its subtypes are named after the specific cell type that is proliferating out of control, including acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML). Leukemia is the most common cancer affecting adolescents and children, and its treatment options may involve chemotherapy, stem cell transplant, immunotherapy, or radiation therapy. The prognosis for leukemia varies depending on the subtype, but the overall 5-year relative survival rate for patients is about 66% in the United States.
2 | The Value of Adaptive Designs in Leukemia Clinical Trials
Unlike traditional studies, adaptive clinical trials offer flexibility while recruitment is still ongoing and are meant to accommodate future design changes depending on their preliminary results. These designs are statistically powered to require fewer patients, making this a valuable approach in leukemia clinical trials where the target population, largely adolescents and young children, may be difficult to enroll. Adaptive designs in multi-arm phase II studies are particularly common; sponsors can assess multiple different novel drugs to conserve more resources, and any arms that show insufficient efficacy results at interim analysis can be dropped early on. As a result, trial costs are reduced, the more successful candidate drugs can proceed to phase III testing, and minimizes the potential risk of exposing children with leukemia to ineffective agents.
3 | Informed Consent and Vulnerable Populations
Although all clinical trials pose a variety of challenges for patients, early-phase leukemia studies are especially complex because this form of cancer affects so many adolescents and young children. The objective for researchers is to test the safety and efficacy of novel therapies in these studies, but parents of affected patients see them as a small chance to overcome the disease once and for all. Furthermore, children are legislatively considered vulnerable populations for research in the US. Sponsors must prepare patient materials which help sites effectively communicate the purpose, benefits, and risks of leukemia clinical trials. Multiple studies have found that parents of children in these programs often have a limited understanding of the research objectives and potential risks involved. By overcoming this challenge, sponsors will maximize their subjects’ protocol compliance and reduce attrition rates by ensuring potential participants and their families are fully educated on clinical trial participation.
4 | Underrepresented Subpopulations of Leukemia Patients
Enrollment challenges are well-known in the world of clinical trials, and although getting the right amount of participants is necessary, recruiting a representative pool of participants is equally important. There is growing evidence supporting the idea that adolescents and young adults (AYA) are underrepresented in cancer therapy research. Not only has this population been associated with a fairly static 5-year survival rate compared with the improvements seen in young children or older adults, but they also have the lowest rates of trial participation. Sponsors can take steps during site selection and trial designs to ease the inclusion of this complicated subpopulation. This age group can often be missed when age limits are added to the eligibility criteria, due to being too young for adult studies yet not young enough for some pediatric trials. Tailoring recruitment plans and promoting trial accessibility for AYA leukemia patients where appropriate expands the pool of potential participants and ensures treatment testing isn’t missed in this significant subset of leukemia patients.
Conclusion
As the most common type of cancer affecting children and young adults, leukemia clinical trials are essential for improving upon current therapies, especially within underrepresented adolescent groups. Discovering therapies for this form of cancer can be especially challenging given the additional risks faced by vulnerable populations like children. Sponsors can better equip their leukemia trials to be more accommodating for participants by integrating adaptive approaches into their protocol design and concisely communicating study information to patient families.
Vial is building towards a more efficient future for clinical trials. Visit https://vial.com/cro/oncology/ to learn how our products deliver faster and more efficient cancer trials for sponsors. Connect with a team member today!
