Sanofi Pasteur, the vaccines division of the sanofi-aventis Group, announced an agreement with KaloBios Pharmaceuticals, a US-based, privately held biotech company, for the development of a Humaneered antibody fragment to both treat and prevent Pseudomonas aeruginosa (Pa) infections. Most serious Pa infections occur in hospitalized and critically or chronically ill patients--primarily affecting the respiratory system in susceptible individuals--and are a serious clinical problem due to their resistance to antibiotics.

Under the terms of the agreement, Sanofi Pasteur acquires worldwide rights to KaloBios' technology for all disease indications related to Pa infections except cystic fibrosis and bronchiectasis, which Sanofi Pasteur has the option to obtain at a later date. KaloBios has already completed phase-I clinical trials - one in healthy volunteers and one in cystic fibrosis patients - and a small proof of concept phase-II clinical trial in mechanically ventilated patients.

"KaloBios has shown convincing safety data in phase I studies and a trend toward efficacy in a phase II study of ventilator-associated pneumonia," declared Wayne Pisano, president and CEO of Sanofi Pasteur. "Hospital-acquired Pa infections are associated with very high levels of morbidity, mortality and costs and treating them represents a significant, unmet medical need. Despite modern antibiotic therapy, treatment failures, relapses and deaths are common," said Pisano.

The two primary target indications for the antibody are prevention of Pa associated pneumonia in mechanically ventilated patients in hospitals as well as prevention of relapses and potential improvement of treatment outcomes in patients with an ongoing Pa infection. Additional indications - both prophylactic and therapeutic - can be considered later in the lifecycle of the product.