Limitations
CIPN, multiple cancer, pain
MULTIPLE CANCER
There are some limitations in the present study. First, the study was an open-label, single-arm study without a comparator group; a placebo group could not be used due to ethical concerns. Therefore, the results cannot be definitively attributed to mirogabalin. However, the degree of pain improvement was similar to that found for duloxetine in previous controlled clinical studies [Second, in the present study, patients were evaluated mostly by oncologists who did not routinely carry out neurological examinations such as testing of tendon reflexes. Physicians were provided with training by viewing a neurologist’s instructional video prior to the start of the study. Previous clinical trials of CIPN often used patients’ subjective evaluations; however, physicians’ objective neurological evaluations are considered essential for accurate evaluation of CIPN severity. The present study design was established via collaboration between oncologists and neurologists and included standardization of assessment procedures, and in this regard may be helpful for future clinical trials of treatments for CIPN.Third, this was a short-term study (12 weeks). Because multiple cancer types and regimens were involved, a longer study period was not possible. However, chemotherapy with oxaliplatin or taxane is often completed in about 6 months [Fourth, no data were collected on modifications of chemotherapy regimens, such as dose reduction from pre-enrollment to enrollment (baseline) or at enrollment. Chemotherapy dose reduction may have had a significant impact on pain and tingling, and on the efficacy results of mirogabalin (its analgesic effects).