Study Does Not Meet Primary Endpoint

SOUTH SAN FRANCISCO, CA, USA I January 29, 2014 I KaloBios Pharmaceuticals, Inc. (KBIO) today announced the completion of the randomized, double-blind placebo-controlled Phase 2 study of KB003, its anti-GM-CSF monoclonal antibody (mAb), in patients with severe asthma. While the study showed that KB003 was generally safe and well tolerated, it did not meet its primary clinical endpoint of improvement in FEV1 (a measurement of pulmonary function) compared to placebo in the overall study population.

 

The company also evaluated improvement in FEV1 compared to placebo in a number of pre-specified subgroup analyses. Of those subgroups, eosinophilic patients (Baseline Blood Eosinophils ≥0.3 GI/L) and patients demonstrating high reversibility at baseline (>20%) showed a statistically significant improvement compared to placebo. Other subgroups such as atopic or non-atopic patients did not demonstrate a statistically significant improvement in FEV1 from baseline as compared to placebo. In the key secondary endpoints evaluated, there was no meaningful reduction in exacerbations observed in patients receiving KB003 in the overall study population or in any material subgroup as compared to those receiving placebo, and there was no statistically significant improvement in asthma control questionnaire (ACQ) scores in the overall patient population.

“The results of this study replicate the effects seen in our earlier Phase 1/2 study in eosinophilic and highly reversible patients. Unfortunately the drug effect did not include improvement in exacerbations and ACQ, nor was the FEV1 improvement seen in the broader patient population evaluated in this study,” said Nestor A. Molfino, MD, MSc., KaloBios’ Chief Medical Officer. “The KaloBios team is working to continue to analyze further the results of the study, and we plan to  meet with thought leaders to better understand the outcomes in the various subgroups of the patient population included in the study. We expect to submit the full results to a scientific meeting or journal for future publication.” 

“We are obviously disappointed in this outcome given the unmet need for additional treatments for severe asthma,” said David Pritchard, KaloBios’ Chief Executive Officer.  “Based on the initial data evaluation of this Phase 2 study, we are discontinuing clinical development of KB003 in severe asthma. Instead we will refocus our resources and efforts on advancing our other products in the clinic, especially KB001-A where we continue to enroll patients in our Phase 2 study evaluating treatment of cystic fibrosis patients with Pseudomonas aeruginosa (Pa) lung infections, and on KB004, our oncology program where we are commencing enrollment of the Phase 2 expansion trial evaluating patients with acute myeloid leukemia and myelodysplastic syndrome.”

Conference Call with Management
Management will host a teleconference and webcast to provide an overview of the trial results later today , January 29, 2014, at 4:30PM Eastern Time (1:30PM Pacific Time).

Interested parties can listen to the live teleconference by dialing (800) 514-4861 from the U.S. and Canada or +1 (484) 756-4333 for international callers. Individuals may access the live audio webcast by visiting the event URL at: http://ir.kalobios.com/events.cfm.  A replay of the webcast will be available on the Company’s website for 30 days following the live event.

KB003 Trial Design
The Phase 2 clinical trial of KB003 in inadequately controlled severe asthma patients was a randomized, double-blind, placebo controlled study evaluating 160 patients randomized one to one between treatment with current standard of care plus either KB003 or placebo. Eligible patients were identified as severe asthma patients having had at least two exacerbations in the preceding 24 months. In addition, in order to participate in the study, eligible patients were required to be diagnosed as reversible at the time of enrollment, defined as patients whose FEV1 improved by 12% or more after receiving treatment via a bronchodilator. Patients enrolled in the 24 week study received, in addition to current standard of care, either placebo or a 400mg dose of KB003 every four weeks via intravenous administration, with one additional dose at week 2. The primary endpoint of the study was the change in FEV1 from baseline for patients in the KB003 arm as compared to those in the placebo arm.  The study was powered at 80% to detect a 6.7% improvement in FEV1 when compared to placebo.  FEV1 is a measurement of pulmonary function.

About KaloBios
KaloBios Pharmaceuticals, Inc. is developing a portfolio of proprietary, patient-targeted, first-in-class monoclonal antibodies designed to treat severe life-threatening or debilitating diseases for which there is an unmet medical need, with a clinical focus on severe respiratory diseases and cancer.Currently, KaloBios has three drug development programs:

  • KB003 is an anti-GM-CSF mAb with potential to treat inflammatory diseases, being developed for the treatment of severe asthma. A Phase 2 clinical study in 160 patients with severe asthma has been completed in the United States, Europe and Australia, which did not meet its primary endpoint of average improvement in FEV1 from baseline as compared to placebo.  KaloBios has discontinued development of this compound in severe asthma, and is continuing to analyze the Phase 2 data to review with thought leaders in order to determine next steps, if any, in the development of KB003.
  • KB001-A is an anti-PcrV mAb fragment, partnered exclusively with Sanofi Pasteur, and is being developed for the prevention and treatment of Pa infection. KaloBios has retained rights for the cystic fibrosis (CF) indication and is conducting a 180 patient Phase 2 study in CF subjects with chronic Pseudomonas aeruginosa (Pa) lung infection in the United States. KaloBios has received Orphan Drug designation from both the U.S. FDA and the European Medicines Agency for KB001-A for the treatment of Pa lung infection in CF patients. Sanofi is pursuing a ventilator-associated pneumonia prevention indication in the intensive care setting, an indication which has received U.S. FDA Fast Track Designation.
  • KB004 is an anti-EphA3 mAb, with potential in treating hematologic malignancies and solid tumors. KaloBios is currently testing this drug in a Phase 1 study in subjects with hematologic malignancies, and intends to initiate a Phase 2 expansion for acute myeloid leukemia and myelodysplastic syndrome in the first quarter of 2014.

All of the company’s antibodies were generated using its proprietary Humaneered® technology, a method that converts nonhuman antibodies (typically mouse) into recombinant antibodies that have a high binding affinity to their target and are designed for chronic therapeutic use. The company believes that antibodies produced using its Humaneered® technology offer important clinical and economic advantages over antibodies generated by other methods in terms of high binding affinity, high manufacturing yields, and minimal to no immunogenicity (inappropriate immune response) upon repeat administration in humans.

SOURCE: KaloBios