Found these two (BOTH are in Madrid, Spain) listed on the Clinical Trials web site:
https://clinicaltrials.gov/ct2/show/NCT01463904?term=Single+Anastomosis+Duodeno-Ileal+Bypass&rank=1
https://clinicaltrials.gov/ct2/show/NCT01685177?term=Single+Anastomosis+Duodeno-Ileal+Bypass&rank=2
https://clinicaltrials.gov/ct2/show/NCT01463904?term=Single+Anastomosis+Duodeno-Ileal+Bypass&rank=1
https://clinicaltrials.gov/ct2/show/NCT01685177?term=Single+Anastomosis+Duodeno-Ileal+Bypass&rank=2