For certain leukemia patients, some welcome findings: New research confirms long remissions after treatment with the drug ibrutinib and chemotherapy.
The study involved 85 patients with chronic lymphocytic leukemia (CLL). All were 65 or younger, and 46 had more aggressive, unmutated IGHV subtype of the disease.
"Patients with lower-risk CLL, which is marked by mutated IGHV genes, can gain long remissions from a six-month regimen known as FCR -- for the chemotherapy drugs fludarabine and cyclophosphamide and the antibody therapy rituximab," Dr. Matthew Davids, of Dana-Farber Cancer Institute in Boston, said in an institute news release.
Patients with higher-risk CLL, without IGHV mutation, typically don't get the same lasting benefit from FCR, but can do very well on ibrutinib (brand name Imbruvica), which blocks an enzyme used by CLL cells to survive.
However, they need to keep taking ibrutinib the rest of their life, which can be challenging due to the ongoing risks and side effects of the drug, Davids explained.
"Our study examined whether a time-limited course of ibrutinib given in combination with FCR can provide lasting remissions for patients with CLL regardless of whether they have the IGHV-mutated or -unmutated subtype," he said.
The study participants received ibrutinib for seven days followed by a combination of ibrutinib and FCR for up to six months. They continued to receive ibrutinib alone for two more years. Those who had no detectable leukemia cells in their bone marrow after the two years stopped taking the drug.
After a median follow-up of more than 40 months, 99% of the patients were still alive and 97% were alive with no worsening of their disease. Those rates are essentially unchanged from an earlier follow-up at 16.5 months.
The few patients whose leukemia recurred after the 2.5-year mark responded well when they started taking ibrutinib again, according to the study. The findings were presented Monday at the annual meeting of the American Society of Hematology.
"We're very encouraged about the potential of this therapy to generate long-term remissions in a broad population of younger patients with CLL," Davids said. "For young patients, in particular, who, hopefully, have decades of life ahead of them, the prospect of a time-limited therapy that can have such durable impact without the need for ongoing treatment is very impactful."
Research presented at meetings should be considered preliminary until published in a peer-reviewed medical journal.
For more on chronic lymphocytic leukemia, go to the American Cancer Society.
SOURCE: Dana-Farber Cancer Institute, news release, Dec. 13, 2021