Document 0644
 DOCN  M9490644
 TI    Pulmonary deposition of aerosolised pentamidine using a new nebuliser:
       efficiency measurements in vitro and in vivo.
 DT    9411
 AU    Ferretti PP; Versari A; Gafa SI; Becquemin MH; Barchi E; Serafini D; Roy
       M; Salvo D; Bouchikhi A; Servizio di Fisica Sanitaria, Arcispedale S.
       Maria Nuova, Reggio; Emilia, Italy.
 SO    Eur J Nucl Med. 1994 May;21(5):399-406. Unique Identifier : AIDSLINE
       MED/94341283
 AB    The therapeutic efficacy of nebulised pentamidine in the prophylaxis of
       Pneumocystis carinii pneumonia (PCP) depends on the absolute pulmonary
       deposition of the drug. We studied the performance of a new nebuliser
       (Pentasave) by comparison both in vitro and in vivo with a standard
       nebuliser (Respirgard II). In vitro, deposition of pentamidine labelled
       with technetium-99m human serum albumin was measured indirectly by
       capturing inhaled particles on an absolute filter and measuring
       radioactivity with a gamma camera. The nebulisers were initially
       assessed with a pentamidine dose of 100 mg in 5 ml at 44 psi and an air
       flow of 10 l/min for Respirgard II and 16 l/min for Pentasave. Nebuliser
       output, expressed as the percentage of the initial nebuliser
       radioactivity captured by the inhalation filter, was 15% +/- 2% (mean
       +/- SD) for Respirgard II, and significantly increased to 23% +/- 3% for
       an initial version and to 33% +/- 2% for the final version of Pentasave.
       Measurements with a gamma camera in a group of ten patients with human
       immunodeficiency virus infection were made in vivo. The results revealed
       that pulmonary drug distributions are good using both Respirgard II and
       Pentasave. The literature reports that once-monthly pulmonary deposition
       of 9 mg pentamidine seems enough to produce prophylactic effects against
       Pneumocystis carinii. We measured pulmonary pentamidine deposition of
       20.22 +/- 4.31 mg (mean +/- SD) using Respirgard II (with 300 mg in 5
       ml) and of 16.00 +/- 7.18 mg using Pentasave (with 150 mg in 6 ml).
       These findings show that the therapeutic dose of pentamidine (9 mg) was
       widely exceeded with both nebulisers. Further investigations might
       demonstrate that about 200 mg and 125 mg pentamidine for Respirgard II
       and Pentasave, respectively, will achieve a pulmonary deposition of
       therapeutic dose, allowing significant savings in terms of drug and
       expense.
 DE    Administration, Inhalation  Adult  Comparative Study  Female  Human  In
       Vitro  Lung/*METABOLISM/RADIONUCLIDE IMAGING  Male  Models, Structural
       *Nebulizers and Vaporizers  Pentamidine/*ADMINISTRATION &
       DOSAGE/PHARMACOKINETICS  Pneumonia, Pneumocystis carinii/PREVENTION &
       CONTROL  Technetium Tc 99m Aggregated Albumin/DIAGNOSTIC USE  JOURNAL
       ARTICLE

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