.
8.5 Geriatric Use
Clinical studies of TOBI Podhaler did not include sufficient numbers of subjects aged 65 years and over to determine whether they respond differently from younger subjects. Tobramycin is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, it may be useful to monitor renal function [see Warnings and Precautions (5.2, 5.5)].
8.6 Renal Impairment
Tobramycin is primarily excreted unchanged in the urine and renal function is expected to affect the exposure to tobramycin. The risk of adverse reactions to this drug may be greater in patients with impaired renal function. Patients with serum creatinine > 2 mg/dL and blood urea nitrogen (BUN) > 40 mg/dL have not been included in clinical studies and there are no data in this population to support a recommendation regarding dose adjustment with TOBI Podhaler [see Warnings and Precautions (5.2, 5.5)].
8.7 Hepatic Impairment
No studies have been performed in patients with hepatic impairment. As tobramycin is not metabolized, an effect of hepatic impairment on the exposure to tobramycin is not expected.
8.8 Organ Transplantation
Adequate data do not exist for the use of TOBI Podhaler in patients after organ transplantation.
10 OVERDOSAGE
The maximum tolerated daily dose of TOBI Podhaler has not been established.
In the event of accidental oral ingestion of TOBI Podhaler capsules, systemic toxicity is unlikely as tobramycin is poorly absorbed. Tobramycin serum concentrations may be helpful in monitoring overdosage.
Acute toxicity should be treated with immediate withdrawal of TOBI Podhaler, and baseline tests of renal function should be undertaken.
Hemodialysis may be helpful in removing tobramycin from the body.
In all cases of suspected overdosage, physicians should contact the Regional Poison Control Center for information about effective treatment. In the case of any overdosage, the possibility of drug interactions with alterations in drug disposition should be considered.
11 DESCRIPTION
TOBI Podhaler consists of a dry powder formulation of tobramycin for oral inhalation only with the Podhaler device. The inhalation powder is filled into clear, colorless hypromellose capsules.
Each clear, colorless hypromellose capsule contains a spray dried powder of 28 mg of tobramycin active ingredient with 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), calcium chloride, and sulfuric acid (for pH adjustment).
The active component of TOBI Podhaler is tobramycin. Tobramycin is an aminoglycoside antibiotic. Its chemical name is O-3-amino-3-deoxy-α-D-glucopyranosyl-(1→4)-O-[2,6-diamino-2,3,6-trideoxy-α-D-ribo-hexopyranosyl-(1→6)]-2-deoxy-L-streptamine; its structural formula is:
Tobramycin has a molecular weight of 467.52, and its empirical formula is C18H37N5O9. Tobramycin is a white to almost white powder; visually free from any foreign contaminants. Tobramycin is freely soluble in water, very slightly soluble in ethanol, and practically insoluble in chloroform and ether.
The Podhaler device is a plastic device used to inhale the dry powder contained in the TOBI Podhaler capsule. Under standardized in vitro testing at a fixed flow rate of 60 L/min and volume of 2 L for 2 seconds, the Podhaler device has a target delivered d
