Since the duration of most studies with IV iron in IBD subjects have been only 4-12 weeks studies there is a need to follow-up on long term safety and efficacy of any maintenance iron therapy.

This study represents subjects from the Lead-in Study (P-Monofer-IBD-01) on iron isomaltoside 1000 (Monofer®) to assess the long term safety of iron isomaltoside 1000 (Monofer®) and its ability to maintain stable haemoglobin in IBD subjects with Iron Deficiency Anaemia (IDA).

Inclusion Criteria:

1. Completed the Lead-in Study or discontinued from Lead-in Study due to intolerance to oral iron.
2. Life expectancy beyond 18 months by Investigator's judgement.
3. Willingness to participate after informed consent. -

Exclusion Criteria:

1. Discontinuation from Lead-in Study (except for due to intolerance to oral therapy).

2. Any major protocol deviation in Lead-in Study.

3. Pregnancy and nursing [To avoid pregnancy, women have to be postmenopausal, surgically sterile, or women of child bearing potential must use one of the following contraceptives during the whole study period and after the study has ended for at least 5 times plasma biological half-life of the investigational medicinal product (5 days): Contraceptive pills, Intrauterine Devices (IUD), contraceptive injections (prolonged-release gestagen), subdermal implantation, vaginal ring, and transdermal patches].

4. Any other medical condition that, in the opinion of Investigator, may cause the subject to be unsuitable for the completion of the study or place the subject at potential risk from being in the study.

5. Patients with a Harvey-Bradshaw Index >8 or Partial Mayo Score (excluding Endoscopy Sub-score) >6 at End of Study Visit of Lead-in Study.

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