After 800 cancer patients enrolled during the first 3 months of the NCI-MATCH trial, organizers have extended a temporary halt in enrollment to gear up for the next phase. The basket study, which matches patients to approved or experimental drugs based on specific genetic mutations in their tumors, is expected to resume in April or May.

Unusually high interest in the NCI-Molecular Analysis for Therapy Choice (NCI-MATCH) trial has prompted its organizers—the NCI and the ECOG-ACRIN Cancer Research Group—to extend a pause in enrollment from January to April or May. When enrollment resumes, the trial is expected to add more than a dozen new treatment arms to the existing 10, along with expanded lab capacity to handle a fresh influx of patients.

In this phase II basket study, launched in August 2015, investigators are analyzing the tumors of previously treated cancer patients to identify “actionable” mutations. Such mutations can be targeted by drugs that have shown efficacy in late-stage clinical trials or are approved for other indications. Patients will then be matched to treatment arms based on their specific genetic abnormality.

A planned pause in enrollment for an interim data analysis—required by the trial's protocol after the first 500 patient screenings—began earlier than expected due to the rapid pace of enrollment, says Robert Gray, PhD, ECOG-ACRIN group statistician and a professor of biostatistics at Dana-Farber/Harvard Cancer Center in Boston, MA. The organizers expected to reach their enrollment threshold over the course of the first year, he says, and were caught by surprise when nearly 800 people signed up during the first 3 months.

“Bearing in mind that this is the largest precision medicine cancer trial ever designed, the reality is that no one knew just how long it would take to reach the 500 registrations needed to trigger the interim analysis,” says Gray. “We assumed a gradual ramp-up based on typical patient registration patterns in our clinical trials.”

Typically, enrollment is modest at the beginning of these trials and gains momentum over time, he says. As such, investigators had expected a maximum of 125 enrollees by November.

“Clearly, there is great interest in precision medicine and targeted treatments,” notes Robert Comis, MD, ECOG-ACRIN co-chair and professor of medicine at Drexel University in Philadelphia, PA. He attributes the brisk accrual of patients in large part to widespread participation by community cancer centers and oncology practices—in addition to major academic medical centers—affiliated with the NCI's Community Oncology Research Program and National Clinical Trials Network. In addition, the NCI eliminated a potential financial hurdle for patients by covering the cost of biopsies and genomic screening.

The temporary halt in enrollment will allow organizers to refine and modify the trial based on their experience to date, says Comis. This spring, after reviewing data from the initial enrollees, investigators plan to release a report on their findings, which will include the diversity of cancer types among participants and the number of those with mutations matching one or more of the current or planned treatment arms.

“We are currently in the midst of a very intense analysis,” says Comis. “We will have the new treatment arms available when enrollment resumes.” –Janet Colwell

For more news on cancer research, visit Cancer Discovery online at http://cancerdiscovery.aacrjournals.org/content/early/by/section.

©2016 American Association for Cancer Research.
2016
American Association for Cancer Research.