Study to Evaluate the Efficacy and Safety of Oxabact (OC5) in Primary Hyperoxaluria Patients Who Are on Dialysis


About this study

The purpose of this study is to determine if Oxalobacter formigenes is effective at lowering plasma oxalate levels in patients with primary hyperoxaluria who are on dialysis.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Signed informed consent (as applicable for the age of the subject). A separate appendix to the informed consent will be signed by patients who will participate in the sub-study.
  • A diagnosis of PH (as determined by standard diagnostic methods).
  • Patient should be on a stable dialysis regimen for at least two weeks before baseline.
  • Pre-dialysis plasma oxalate ≥ 40 micromole/L.
  • Subjects receiving vitamin B6 must be receiving a stable dose for at least 3 months prior to entry into the study and must remain on the stable dose during the study. Subjects not receiving vitamin B6 at study entry must be willing to refrain from initiating vitamin B6 during study participation.

Exclusion Criteria:

  • Ongoing treatment with immunosuppressive medication.
  • The existence of secondary hyperoxaluria; e.g., hyperoxaluria due to bariatric surgery or chronic gastrointestinal diseases such as cystic fibrosis, chronic inflammatory bowel disease and short-bowel syndrome.
  • Use of antibiotics to which O. formigenes is sensitive, including current antibiotic use, or antibiotics use within 14 days of initiating study medication.
  • Current treatment with a separate ascorbic acid preparation.
  • Pregnancy.
  • Women of childbearing potential who are not using adequate contraceptive precautions. Sexually active females, unless surgically sterile or at least 2 years post-menopausal, must be using a highly effective contraception (including oral, transdermal, injectable, or implanted contraceptives, IUD, abstinence, use of a condom by the sexual partner or sterile sexual partner) for 30 days prior to the first dose of OC5 and must agree to continue using such precautions during the clinical study.
  • Presence of a medical condition that the Principal Investigator considers likely to make the subject susceptible to adverse effect of study treatment or unable to follow study procedures.
  • Participation in any study of an investigational product, biologic, device, or other agent within 30 days prior to the first dose of OC5 or not willing to forego other forms of investigational treatment during this study.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Dawn Milliner, M.D.

Closed for enrollment

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