KaloBios Pharmaceuticals, has recently provided an update on the status of the KB001-A development programme, including an update on its KB001-A collaboration with Sanofi Pasteur.  

KaloBios has reached an agreement with Sanofi Pasteur to regain all rights to KaloBios' KB001-A programme. Under this agreement, the collaboration and licencing agreement entered into in 2010 has been terminated. Under that collaboration agreement, Sanofi Pasteur had been developing KB001-A, a patented monoclonal antibody targeting Pseudomonas aeruginosa (Pa), for Pa pneumonia prevention in the intensive care setting while KaloBios had been developing KB001-A for chronic treatment of Pa lung infections in cystic fibrosis (CF) patients.

"We are grateful to Sanofi for the work they did to advance the KB001-A programme, including their global epidemiology study that supports KaloBios' assumptions about the large market potential for KB001-A in ventilator-associated pneumonia (VAP). At the same time, we are pleased to regain the global rights for KB001-A across all indications," said David Pritchard, KaloBios' President and Chief Executive Officer. "We continue to believe in the potential of this innovative therapy as a means to address Pa infections in a variety of settings. This negotiated termination not only provides us with full unencumbered rights to our cystic fibrosis indication, but will enable us to seek a partner with established capabilities in additional indications as well as in territories outside of the United States. We will immediately embark on a process to identify a partner with a focus on infectious disease, hospital pharmaceuticals, or cystic fibrosis who can accelerate and financially support the pivotal studies for KB001-A. "

Sanofi Pasteur agreed to terminate the collaboration and licensing agreement with KaloBios in consideration of low single digit royalties on net sales of KB001-A, subject to a $40 million cap on the aggregate royalties to be paid. In addition, Sanofi Pasteur will be entitled to receive up to 10per cent of certain sub-license payments or other milestone payments received in the event KaloBios successfully re-partners KB001-A, subject to a separate $40 million cap on the aggregate amount of sub-license payments to be shared with Sanofi Pasteur.

KaloBios also announced that it has achieved full enrollment in the 180 patient Phase 2 study evaluating KB001-A in CF subjects with chronic Pa lung infection. KaloBios now expects to release top-line data on this study in early first quarter 2015.

"Enrollment increased dramatically in the last few months due to a number of factors, including additional ex-U.S. sites coming on line and enrolling patients, decreased competition from other studies in the cystic fibrosis space, and some seasonal benefit due to patient availability in the summer months," said Nestor A. Molfino, MD, MSc, chief medical officer of KaloBios. "As a result we were able to make up ground and complete enrollment in the KB001-A Phase 2 study in a timeframe that should enable us to release top-line data in early first quarter 2015."

KaloBios had previously completed a Phase 1/2 study with KB001 in thirty-five patients colonised with Pa which demonstrated approximately a 50per cent reduction in VAP in patients treated with KB001.  The study also showed a dose-dependent increase in bacterial event-free survival relative to placebo. The results of this study were published in Critical Care Medicine, and represented the primary efficacy data included in the Sanofi Pasteur regulatory submission under which the VAP indication received Fast Track Status from the FDA. In a separate Phase 1/2 study conducted with CF patients, KaloBios showed a trend towards a dose-dependent reduction in several key inflammatory markers, including neutrophil elastase, when measured 28 days after a single dose of KB001. The results of this study were published in Pediatric Pulmonology.  KaloBios is currently conducting a 180 patient Phase 2 study of KB001-A in CF subjects with chronic Pa lung infection.