A major clinical trial has confirmed what scientists had hoped to disprove: the drug duloxetine, while helpful for cancer patients after nerve damage develops, cannot stop that damage from occurring in the first place. The study, the largest randomized trial to date specifically designed to test whether duloxetine can prevent chemotherapy-induced peripheral neuropathy, enrolled 199 adults with stage II or III colorectal cancer across 73 cancer centers in the United States. The results, published in JCO Oncology Advances, found no meaningful difference between patients taking duloxetine and those receiving a placebo.
Oxaliplatin is a standard chemotherapy drug for colorectal cancer, but it frequently causes peripheral neuropathy—a sometimes permanent condition involving numbness, tingling, and pain in the hands and feet. Duloxetine is already the go-to treatment once that neuropathy has taken hold. Dr. Ellen M. Lavoie Smith, Interim Associate Dean of Research and Scholarship at the University of Alabama at Birmingham School of Nursing, designed the trial to test whether acting early might spare patients entirely. "Since we know duloxetine is effective at treating painful neuropathy caused by neurotoxic chemotherapy drugs, we wanted to see if the medication could also prevent the side effect from developing in the first place," she said.
In the double-blind study, participants with no pre-existing neuropathy were divided into three groups: one received 30 milligrams of duloxetine daily, another received 60 milligrams daily, and the third received a placebo. Treatment began on the first day of oxaliplatin-based chemotherapy and continued for 17 weeks. Researchers tracked neuropathy severity and onset using patient-reported measures several weeks after chemotherapy ended. Neither dose of duloxetine performed better than the placebo.
The finding, while disappointing, offers clear guidance for oncologists and patients. "While duloxetine remains an important option for managing painful chemotherapy-induced neuropathy once it develops, this trial confirms that it should not be used for prevention," Dr. Smith said. The research also underscores an enduring challenge in cancer care: chemotherapy saves lives, but the nerve damage it can cause may linger for years, affecting survivors' daily lives long after treatment ends. Understanding what does not work, researchers say, is just as crucial as discovering what does—and this rigorous trial gives the field a solid foundation from which to keep searching.