Long-term Efficacy and Safety of Lamazym for the Treatment of Patients With Alpha-Mannosidosis

Inclusion Criteria: * The subject must have participated in the phase 1 trial (EudraCT number: 2010-022084-36) and phase 2a trial (EudraCT number: 2010-022085-26) * Subject or subjects legally authorized guardian(s) must provide signed, informed consent prior to performing any trial-related activities (trial-related activities are any procedures that would not have been performed during normal management of the subject) * The subject and his/her guardian(s) must have the ability to comply with the protocol Exclusion Criteria: * The subject cannot walk without support * Presence of known chromosomal abnormality and syndromes affecting psychomotor development, other than alpha-Mannosidosis * History of bone marrow transplantation * Presence of known clinically significant cardiovascular, hepatic, pulmonary or renal disease or other medical conditions that, in the opinion of the Investigator, would preclude participation in the trial * Any other medical condition or serious intercurrent illness, or extenuating circumstance that, in the opinion of the investigator, would preclude participation in the trial. * Pregnancy: Before the start of the treatment the investigators will decide whether or not there is a need for contraception. This assessment will be done through interviews with the patient and parents. The evaluation will be done continuously during the study * Psychosis within the last 3 months * Planned major surgery that, in the opinion of the investigator, would preclude participation in the trial * Participation in other interventional trials testing IMP except for studies with Lamazym