Pharmacokinetic and Pharmacoscintigraphic Comparison of TobrAir® 6.0 With TOBI® and TOBI® Podhaler™

This is an open-label, randomized, single dose, cross-over study in healthy subjects. Each subject receives tobramycin with 3 different inhalation devices:

• 75 mg tobramycin delivered to the airways via TobrAir® 6.0.
• 300 mg tobramycin (TOBI®) delivered to the airways via the PARI LC® PLUS/PARI TurboBoy® SX.
• 112 mg tobramycin (4x28mg dry powder capsules) delivered to the airways via the TOBI® Podhaler™.

Each dose is separated by a minimum washout of at least 68 h.

Blood samples for PK analysis of tobramycin will be collected at regular time intervals until 24 h post-dose. For TobrAir 6.0 and TOBI/PARI only, all dosed subjects will undergo scintigraphic assessments.

Inclusion criteria

• Healthy males or non-pregnant, non-lactating healthy females
• Aged 18 to 65 years
• Body mass index of 18.0 to 29.0 kg/m2 or, if outside the range, considered not clinically significant by the investigator
• Must provide written informed consent
• Must agree to use an adequate method of contraception

Exclusion criteria

• Participation in a clinical research study within the previous 3 months
• Subjects who have previously been enrolled in this study
• Females of childbearing potential who are pregnant or lactating (female subjects must have a negative urine pregnancy test at admission and be using an appropriate method of contraception)
• Radiation exposure, including that from the present study, excluding background radiation but including diagnostic x-rays and other medical exposures, exceeding 5 mSv in the last 12 months or 10 mSv in the last 5 years. No occupationally exposed worker, as defined in the Ionising Radiation Regulations 1999, shall participate in the study
• History of chronic respiratory disorders (including asthma) as judged by the investigator