Plain-English translation of NCT05655780 on ClinicalTrials.gov ↗ · Source last updated · Translation generated · How we translate trials
Read our Colorectal Neoplasms research guide →The OPTIMA study is testing whether doctors can better predict how well irinotecan will work for your advanced colorectal cancer—and reduce harmful side effects—by looking at three things: your tumor's molecular profile, your genes (specifically the UGT1A1 gene), and the enzymes in your gut bacteria. This medication is a standard treatment for advanced colorectal cancer, but it doesn't work the same way for everyone, and some people experience severe side effects. By understanding your individual biology, doctors hope to personalize your dose and predict which patients will benefit most.
Irinotecan can work very well for some patients but causes unpredictable side effects in others, and it doesn't help all patients equally. This trial exists to find better ways to predict who will benefit from this treatment and who is at risk for serious complications, so doctors can adjust your dose or plan ahead to keep you safer.
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You will have blood and stool samples collected to determine your UGT1A1 genotype and measure the enzyme activity in your gut bacteria. Based on these results, your doctor will personalize your irinotecan dose and monitor you closely throughout treatment. The study will also track your tumor's response, any side effects you experience, and your quality of life—likely through regular clinic visits and possibly a dietary intervention to support your gut health.
AI-generated summary from trial data · Jun 18, 2026 · Not medical advice
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