An observational study in Solid Cancer, Gastric (Cardia, Body) Cancer and Esophageal Cancer, sponsored by Erasmus Medical Center. Recruiting at 1 site in Netherlands. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-08-11.
Sponsored by Erasmus Medical Center · Observational
In this study, the drug capecitabine is investigated. Capecitabine is commonly used to treat breast, colon, and stomach cancers. Capecitabine is taken in tablet form. In the body, capecitabine is converted into the active molecule that has anti-cancer effects. This molecule is called 5-FU. The transformation of capecitabine to 5-FU occurs through specific proteins in the liver, also known as enzymes.
Unfortunately, capecitabine can also cause side effects. One of the most common side effects is hand-foot syndrome. In hand-foot syndrome, the palms of the hands and soles of the feet become red and painful. Previous research has shown that patients in whom one of the enzymes responsible for converting capecitabine in the liver does not function properly experience an increase in side effects frequency, particularly severe hand-foot syndrome. This specific enzyme is called CES1. It is believed that side effects occur more frequently because capecitabine is transformed more slowly, eventually leading to a prolonged exposure to 5-FU in the body.
In roughly one in three people, this enzyme functions less efficiently. To gain a better understanding of how this mechanism works, we aim to conduct this study. In this study, we will examine if patients with a less effective CES1 enzyme have higher amounts of 5-FU in their blood. We will also look into whether these patients develop side effects, such as hand-foot syndrome, more frequently. This information could eventually help us develop new strategies to reduce side effects for these patients in the future.
10,818 studies on the registry are indexed under Neoplasms; 2,324 are open to participants now.
This study's planned enrollment of 66 is below the median of 200 across 2,638 observational studies indexed under Neoplasms.
Browse Neoplasms studies →Erasmus Medical Center is the lead sponsor of 478 studies on the registry; 183 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients with cancer who are intended to start with CAPOX treatment.
In order to be eligible to participate in this study, a subject must meet all of the following criteria:
Exclusion Criteria:
A potential subject who meets any of the following criteria will be excluded from participation in this study:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Oncological patients who are treated with CAPOX (with or without additional anti-neoplastic agents, including but not limited to nivolumab, trastuzumab or bevacizumab) according to standard of care. These patients are known carriers of the CES1 1165-33 C\>A (rs2244613) SNP.
Drug: Blood sampling for pharmacokinetics
Oncological patients who are treated with CAPOX (with or without additional anti-neoplastic agents, including but not limited to nivolumab, trastuzumab or bevacizumab) according to standard of care. These patients are known carriers of the wild-type CES1 gene.
Drug: Blood sampling for pharmacokinetics
Extra blood samples are collected for assement of the pharmacokinetics of capecitabine.
This study also gives Trastuzumab, Nivolumab. No intervention listed here names it: that was found by reading the record.
Pharmacokinetic Exposure
Difference in Area Under the Curve (AUC)
Time frame: Up to 6 hours after intake of capecitabine
Started Feb 2025 (actual). Primary completion is estimated for Dec 2026, 22 months after the start.
Of 1,098 non-industry observational studies under Neoplasms, half reached primary completion within 61 months of starting (the median), counting those still running; a quarter within 24 and three quarters within 227. This study's planned 22 months is below that.
Counting every sponsor, half of 1,246 studies reached it within 58 months; a quarter within 24 and three quarters within 210.
Neoplasms covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
No contact was published for this record. The registry link below has the sponsor’s details.
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