Amikacin Inhale Shows Promising Results In Study

Bayer HealthCare together with Nektar Therapeutics, presented positive preliminary Phase II data on their unique drug-device combination Amikacin Inhale at the American Thoracic Society (ATS) annual meeting. Amikacin Inhale, currently being studied for the adjunctive treatment of Gram-negative pneumonia in intubated and mechanically-ventilated patients, achieved over 1000 times greater lung exposure to the antibiotic amikacin as compared to intravenous route of administration. This shows that targeting antibiotic therapy to the site of infection might offer superior bacterial eradication and increased efficacy, which may result in a higher likelihood of the patient's survival. Currently, Gram-negative pneumonia carries a mortality risk as high as 50 percent in mechanically-ventilated patients.

"Mechanically-ventilated patients in critical care units are at particularly high risk of developing pneumonia. Most of them are already seriously ill because of severe underlying diseases," said Professor Michael Niederman, Chairman, Department of Medicine, Winthrop University Hospital, New York, and one of the lead investigators of the study. "Because of the high morbidity and mortality of Gram-negative pneumonia, fast and efficient treatment is essential. Intravenous therapies cannot always reach effective concentrations in infected lungs at tolerable doses. The new study data shows that the device successfully delivers the antibiotic directly to the site of infection, without reaching high systemic concentrations."

Amikacin Inhale is a unique drug-device combination, being developed by Bayer HealthCare in cooperation with Nektar Therapeutics, combining a special liquid formulation of the aminoglycoside antibiotic amikacin with Nektar Therapeutics' proprietary Liquid Pulmonary Technology (LPT), designed to deliver amikacin deep into the infected lungs.

The device can be integrated into mechanical ventilation systems and can also be used as a handheld 'off-vent' device for patients no longer requiring breathing assistance. This allows for a unique full course of drug therapy in critically ill patients with Gram-negative pneumonia. 'Gram-negative pneumonia' refers to pneumonia caused by a laboratory-defined group of pathogens, the Gram-negative bacteria. These account for a substantial proportion, if not the majority of pneumonias in intensive care units (ICUs).

"A challenge in treating Gram-negative pneumonia in ICUs is that they have grown increasingly resistant to currently available antibiotics," said Professor Donald Low, Head of the Department of Microbiology at the Toronto Medical Laboratories and Mount Sinai Hospital, Toronto, Canada. "A new treatment option such as Amikacin Inhale, which fights pneumonia directly at the site of infection, may be able to help decrease resistance -- especially if concomitant intravenous antibiotic therapy can also be reduced."

Amikacin Inhale will enter Phase III trials later this year to further assess its efficacy and safety in mechanically ventilated patients with Gram-negative pneumonia. The enrolment for two pivotal Phase III studies will start in the fourth quarter of 2008.