臨床研究等提出・公開システム

Efficacy of endoscopic closure using MANTIS Clip for mucosal defects after colorectal endoscopic submucosal dissection.

MANTIS study

21

Of the 21 cases included in the FAS, 8 were male (38.1%), the mean age was 69.1 years (standard deviation 11.3 years), and the median age was 73 years (range: 46-83 years). ECOG-PS was 0 for all patients. The mean lesion diameter (tumor long diameter) was 36.29 mm, with a median of 35 mm (range: 30-50 mm). Two patients (9.5%) were taking antithrombotic drugs.

In this study, 22 participants were enrolled against the target enrollment number of 22, achieving a 100% enrollment completion rate. All enrolled participants met the eligibility criteria, and there were no ineligible cases. Enrollment took place from April 2024 to May 2025. From June 20, 2024, to November 11, 2024, new enrollment was temporarily suspended in response to a serious non-compliance, but enrollment progressed after resumption, reaching the target number of cases within the planned enrollment period. Regarding the treatment course, follow-up was completed for 21 out of 22 participants, and one participant discontinued due to an intraoperative adverse event (intestinal perforation). At the time of reporting, there were no participants still under follow-up.

No intraoperative adverse events were observed. Adverse events Observed 1-5 days postoperatively included PECS in 3 patients (14.3%), postoperative bleeding in 4 patients (19.0%), anemia in 3 patients (14.3%), lower gastrointestinal bleeding in 1 patient (4.8%), and anal pain and abdominal pain in 1 patient each (4.8%). In addition, hypoalbuminemia was reported in 5 patients (23.8%); increased creatinine, hyponatremia, elevated serum bilirubin, and elevated lactate dehydrogenase levels were each observed in 2 patients (9.5%); and hypokalemia was reported in 1 patient (4.8%). Grade 3 events were limited to two cases of PECS. No adverse events were observed beyond postoperative day 28.

The primary efficacy endpoint of this study, the complete closure success rate, was 95.2% (exact 95% confidence interval [CI], 76.2%-99.9%). In addition, the following secondary endpoints were evaluated: closure time, the proportion of maintained closure at postoperative days 3-5, clip detachment status at 2 weeks after the procedure, the incidence of adverse events, and the incidence of medical device malfunctions. The mean closure time was 18.95 minutes (standard deviation, 10.55 minutes). The proportion of maintained closure at postoperative days 3-5 was 76.2% (95% CI, 52.8%-91.8%). Regarding clip detachment status at 2 weeks after the procedure, there was no detachment in 1 case (4.8%), detachment in 17 cases (81.0%), and complete detachment in 3 cases (14.3%). Regarding the incidence of medical device malfunctions, there were 4 cases with malfunctions (19.0%; 95% CI, 5.4%-41.9%) and 17 cases without malfunctions (80.9%; 95% CI, 58.1%-94.6%).

The results of this study suggest that the closure technique using the Mantis Clip achieved a high rate of complete closure and demonstrated a certain level of effectiveness. However, regarding safety, adverse events and medical device malfunctions were observed only during the early postoperative period.

Sept. 16, 2026

Sept. 09, 2026

https://www.clinicalkey.jp/#!/content/playContent/1-s2.0-S0016510726070392?returnurl=null&referrer=null

Yes

De-identified individual participant data collected in this study may be shared after the primary conclusions of the study have been obtained, upon reasonable request for secondary analyses, linked clinical studies, or integrated analyses such as meta-analyses. Only data from participants who provided written consent for future secondary use of their data will be eligible for sharing. Data sharing will be subject to approval by the administrator of the study site or the certified review board (CRB), as applicable. Applicants must submit a data request form describing the purpose of use and the required data items, and the principal investigator will determine whether the request can be granted.

https://jrct.mhlw.go.jp/latest-detail/jRCT1042240004

Imai Kenichiro

Shizuoka Cancer Center

1007Shimonagakubo, Nagaizumi-cho, Sunto-gun, Shizuoka

ke.imai@scchr.jp

Ashizawa Hiroshi

Shizuoka Cancer Center

1007Shimonagakubo, Nagaizumi-cho, Sunto-gun, Shizuoka

+81-55-989-5222

h.ashizawa@scchr.jp

Complete

April. 03, 2024

Interventional

single arm study

open(masking not used)

uncontrolled control

single assignment

treatment purpose

1 Early colorectal cancer, size 30-50 mm in endoscopic image
2 Scheduled for treatment with ESD.
3 More than 18 years of age
4 Performance status, 0-1
5 Patients with provided written informed consent

1 Patients with bleeding tendency
2 Continuation of more than two antithrombotic
agents during endoscopic resection or
requirement of heparin bridging for past comorbid
illness
3 Patients with nickel sensitivity
4 Patients judged by the study director or resear
cher to be ineligible for the study

Both

Early colorectal cancer

Early colorectal cancer with 30-50 mm in size is enrolled, and perform endoscopic closure using MANTI Clip for mucosal defects after colorectal ESD.

Rate of complete closure achieved (At the end of protocol treatment)

1 Closure time
2 Rate of closure maintained at 3-5 days
3 Rate of clip dropout at 2 weeks
4 Adverse events rate
5 Rate of medical device failures

+81-55-989-5222

Feb. 21, 2024

none