PHILADELPHIA — The National Cancer Institute (NCI) Molecular Analysis for Therapy Choice (MATCH) clinical trial has achieved the goal of screening nearly 6,000 patients in just under two years, according to data presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, held Oct. 26-30. Eighteen percent of tumors screened were found to have a genetic mutation that matched the patient to one of the 30 treatment arms.
“NCI-MATCH is a precision medicine clinical trial designed to explore signals of treating patients based on their molecular aberration regardless of histology of their tumor,” said Alice P. Chen, MD, head of the Early Clinical Trials Development program in the Division of Cancer Treatment and Diagnosis at the NCI in Bethesda, Maryland. “If 25 percent or more of the patients with a given mutation that matches them to a specific treatment arm respond to the treatment, it would mean that the particular treatment-mutation combination is worthy of further study in a larger phase II clinical trial.
“In almost two years, we have screened nearly 6,000 patients whose cancer has progressed despite standard treatment. This rate of screening far exceeded our expectations and likely reflects the broad interest in the promise of genomics and the study design of NCI-MATCH, which offered treatment based on genetic characteristics of the tumor,” continued Chen. “The activity of each drug will be analyzed when 31–70 patients have been treated to determine whether matching drugs to molecular targets results in improved patient outcome and what tumor types are more likely to respond.”
As of July 16, 2017, 5,963 tumor samples from patients with a wide range of cancer types at more than 1,000 clinical sites around the United States had been screened using next-generation sequencing at one of four central gene-sequencing laboratories. The most common types of cancer accounted for just 38.2 percent of the cancers screened; most were rarer cancer types.
The sequencing assay successfully yielded a result 93 percent of the time, which is well above the industry average of about 80 percent, according to Chen.
Eighteen percent of the tumors successfully sequenced harbored a mutation that matched the patient to one of the 30 treatment arms in NCI-MATCH. Of these 998 patients, 69 percent enrolled in the treatment arm to which they were matched. The prevalence of each arm’s mutation varied substantially, with one mutation observed in as many as 3.47 percent of the patients who were screened, while one mutation was not observed in any of the almost 6,000 patients. Therefore, patient accrual to each arm has been variable. Eight of the 30 treatment arms have reached the minimum patient accrual goal of 35, and some of these have been expanded to allow for accrual of up to 70 patients.
As a result of the low prevalence rate of some of the mutations, some of the treatment arms did not accrue 35 patients within the initial screening cohort of nearly 6,000 patients. “Accrual to these arms has been amended so patients who have had their tumor sequenced at approved laboratories in the course of their clinical care can enter the study if they have a qualifying mutation and meet eligibility criteria for an arm,” said Chen. Any qualified laboratory can apply for approval to the NCI-MATCH committee.
According to Chen, the main limitations of the study are that the sample size for each treatment arm is relatively small, which means that the number of cases with a particular histology for a given treatment may be limited, and the patients referred to the trial tend to be heavily pretreated, making broad applicability limited as well. However, if there is a signal in a heavily pretreated population, it suggests potentially exciting activity for the agent that can then be followed up on in additional trials that target the responding population.
NCI-MATCH is supported by funds from the NCI and is coordinated by the ECOG-ACRIN Cancer Research Group. The NCI is part of the National Institutes of Health (NIH).
Chen declares no conflicts.