Duloxetine may help reduce pain from chemotherapy

Among patients with painful chemotherapy-induced peripheral neuropathy, use of the anti-depressant drug duloxetine for 5 weeks re­sulted in a greater reduction in pain compared with placebo, according to a study in JAMA.

“Approximately 20 percent to 40 percent of patients with cancer who re­ceive neurotoxic chemotherapy (e.g., taxanes, platinums, vinca alkaloids, bortezomib) will develop pain­ful chemotherapy-induced peripheral neuropathy. Painful chemotherapy-induced neuropathy can persist from months to years beyond chemotherapy completion, causing significant challenges for cancer survivors due to its negative in­fluence on function and quality of life. Chemotherapy-induced pe­ripheral neuropathy is difficult to manage, and most randomised controlled trials testing a variety of drugs with diverse mechanisms of action revealed no effective treatment,” according to background information in the article.

There is evidence that serotonin and norepinephrine dual reuptake inhibitors are effective in treat­ing neuropathy-related pain. Several phase 3 stud­ies have shown that duloxetine is an effec­tive treatment for painful diabetic neu­ropathy.

Ellen M. Lavoie Smith, Ph.D., of the University of Michigan School of Nursing, Ann Arbor, and colleagues conducted a ran­domised phase 3 trial to examine whether duloxetine would lessen chemotherapy-induced peripheral neuropathic pain. The study included 231 patients who were 25 years or older being treated at community and academic settings between April 2008 and March 2011. Study follow-up was com­pleted July 2012. Stratified by chemotherapeutic drug and comorbid pain risk, pa­tients were randomised to receive either duloxetine followed by placebo or placebo followed by duloxetine. Eligibility required that patients have a pain score of at least 4 on a scale of 0 to 10, representing average chemotherapy-induced pain, after paclitaxel, other taxane, or oxaliplatin treatment.

The initial treatment consisted of taking 1 capsule daily of either 30 mg of duloxetine or placebo for the first week and 2 capsules of either 30 mg of du­loxetine or placebo daily for 4 additional weeks.

The researchers found that at the end of the initial treatment pe­riod, patients in the duloxetine-first group reported a larger decrease in av­erage pain (average change score, 1.06) than those in the placebo-first group (average change score 0.34). The observed average differ­ence in the average pain score between the duloxetine-first and placebo-first groups was 0.73. Of the patients treated with dulox­etine first, 59 percent reported any decrease in pain vs. 38 percent of patients treated with placebo first. Thirty percent of duloxetine-treated patients reported no change in pain and 10 percent reported in­creased pain.

The authors note that the results sug­gested that patients who received plati­nums (oxaliplatin) may have experienced more benefit from duloxetine than those who received taxanes.

Pain-related quality-of-life im­proved to a greater degree for those treated with duloxetine during the ini­tial treatment than for those treated with placebo.

“In conclusion, 5 weeks of duloxetine treatment was associated with a statisti­cally and clinically significant improve­ment in pain compared with placebo. Exploratory analyses raise the possibility that duloxetine may work better for oxaliplatin-induced rather than taxane-induced painful chemotherapy-induced peripheral neuropathy,” the researchers write.

(Source: For the Media: Journals of the American Medical Association)

More information

For more information about nausea and vomiting in cancer treatment, including ways to manage it, see Chemotherapy-Induced Nausea and Vomiting (CINV).