Can Recombinant Human Intrinsic Factor Be Used for Evaluation of the Vitamin B12 Absorption?

University of Aarhus

Status and phase: Completed; Phase 2

Conditions: Vitamin B12 Deficiency

Treatments: Drug: Recombinant human intrinsic factor

Study type: Interventional

Funder types: Other

Identifiers

NCT00279552

20030267

Details and patient eligibility

About

Vitamin B12 is an essential nutrient for normal DNA-synthesis and must be supplied by animal products. Vitamin B12 deficiency may cause anemia and irreverible neurological damage. Laboratory tests are used for diagnosis of vitamin B12 deficiency, and following the diagnosis, the cause of the vitamin B12 deficiency has to be clarified. For years a test called Shilling's test has been used for evaluation of the vitamin B12 absorption. However, the Schilling's test is no longer easy accessible because of increasing difficulties to obtain the radioactively labeled vitamin B12 requested, and native human intrinsic factor for Schilling's test II (absorption of vitamin B12 attached to intrinsic factor) is no longer available in most countries. Recently, human intrinsic factor unsaturated with vitamin B12 has been expressed in the plant Arabidopsis thaliana. The purpose of this study was to examine whether recombinant human intrinsic factor is able to promote the uptake of vitamin B12 in patients with evident vitamin B12 deficiency.

Full description

Vitamin B12 is an essential nutrient for normal DNA-synthesis and must be supplied by animal products. Vitamin B12 deficiency may cause anemia and irreverible neurological damage. Laboratory tests are used for diagnosis of vitamin B12 deficiency, and following the diagnosis, the cause of the vitamin B12 deficiency has to be clarified. For years a test called Shilling's test has been used for evaluation of the vitamin B12 absorption. However, the Schilling's test is no longer easy accessible because of increasing difficulties to obtain the radioactively labeled vitamin B12 requested, and native human intrinsic factor for Schilling's test II (absorption of vitamin B12 attached to intrinsic factor) is no longer available in most countries. Recently, human intrinsic factor unsaturated with vitamin B12 has been expressed in the plant Arabidopsis thaliana. The purpose of this study was to examine whether recombinant human intrinsic factor is able to promote the uptake of vitamin B12 in patients with evident vitamin B12 deficiency.

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Patients suspected to have vitamin B12 deficiency defined as a plasma vitamin B12 below the reference interval (<200 pmol/L).

Exclusion criteria

Patients who were pregnant, nursing or not able to give written informed consent were excluded.

Trial design

Primary purpose: Diagnostic

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)