The main purpose of this study is to assess the relative bioavailability of Nascobal Nasal Spray as compared to an IM injection of cyanocobalamin (European reference product).

This is an open-label, randomized, single-dose, two-way crossover study. The study consists of a screening visit, two 4-days confinement periods and a follow-up telephone call. The two confinement periods will be separated by a washout period of at least 28 days.

Inclusion Criteria:

• Healthy female and male voluteers
• 18-40 years of age
• BMI between 18.5 and 30.0 kg/m2

Exclusion Criteria:

• Females who are pregnant or lactating
• History of clinically significant metabolic, hepatic, renal, haematological, pulmondary, cardiovascular, gastrointestinal, urological, neurological or phychiatric disorders
• Serum vitamin B12 <=250 pmol/L or MMA >=0.40 umol/L
• Evidence of significant intranasal pathology
• Nasal congestion, allergic rhinitis or upper respiratory tract infection