Study to Evaluate the Efficacy and Safety of Oxabact (OC5) in Patients With Primary Hyperoxaluria

OxThera

Status and phase: Completed; Phase 2; Phase 1

Conditions: Primary Hyperoxaluria

Treatments: Drug: Placebo capsules; Biological: Oxabact OC5 capsules

Study type: Interventional

Funder types: Industry; Other

Identifiers

NCT02012985

OC5-DB-01

Details and patient eligibility

About

The purpose of this study is to determine if Oxalobacter formigenes is effective at lowering urinary oxalate levels in patients with primary hyperoxaluria.

Enrollment: 28 patients

Sex: All

Ages: 2+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Signed informed consent (as applicable for the age of the subject).
• Male or female subjects ≥ 2 years of age (Germany & France) / Male or female subjects ≥ 5 years of age (United Kingdom)
• A diagnosis of PH type I, II or III (as determined by standard diagnostic methods).
• A mean urinary oxalate excretion of > 1.0 mmol/24h/1.73m2, based on at least three eligible urine collections performed during baseline (weeks 1-4).
• Renal function defined as an estimated GFR ≥ 40 ml/min normalised to 1.73m2 body surface area, or a creatinine clearance of ≥ 40 ml/min normalised to 1.73m2 body surface area.
• Subjects receiving vitamin B6 must be receiving a stable dose for at least 3 months prior to screening and must not change the dose during the study. Subjects not receiving vitamin B6 at study entry must be willing to refrain from initiating pyridoxine during study participation.

Exclusion criteria

• Inability to collect complete 24-hour urine samples. Each urine collection will be evaluated for completeness based on urine qualitative criteria.
• Inability to swallow size 4 capsules twice daily for 8 to 10 weeks.
• Subjects that have undergone transplantation (solid organ or bone marrow).
• 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 chronic use, a history of more than two courses of antibiotic use during the past 6 months, current antibiotic use, or antibiotics use within 14 days of initiating study medication.
• Subjects who require immune suppressive therapy.
• Current treatment with ascorbic acid preparation.
• Pregnancy.
• Women of child-bearing potential who are not using adequate contraceptive precautions such as oral, transdermal, injectable, or implanted contraceptives, IUD, complete abstinence, use of a condom by the sexual partner, or sterile sexual partner.
• 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 screening or not willing to forego other forms of investigational treatment during this study.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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28 participants in 2 patient groups, including a placebo group

Oxabact OC5 capsules

Experimental group

Description:

The active study drug consists of Oxalobacter formigenes OC5 in enteric-coated size-4 capsules. The dose (not less than (NLT) 1E+09 colony forming units (CFU)) will be administrated orally with breakfast and dinner as one capsule two times per day for 8 to 10 weeks.

Treatment:

Biological: Oxabact OC5 capsules

Placebo capsules

Placebo Comparator group

Description:

The placebo study drug consists of microcrystalline cellulose in enteric-coated size-4 capsules. It has been manufactured to mimic the OC5 capsule. The dose will be administrated orally with breakfast and dinner as one capsule two times per day for 8 to 10 weeks.

Treatment:

Drug: Placebo capsules