The novel respiratory antibiotic, Cethromycin, was shown to be effective in preventing inhalation anthrax infection. This conclusion was reached from a primate study where a 30-day course of oral Cethromycin was 100% protective against a lethal dose of inhaled anthrax as compared to the standard of care, Cipro(R) (ciprofloxacin), which demonstrated 90% protection.
“We felt confident going into the primate study because of Cethromycin’s potent activity against over 30 strains of anthrax, yet the results have exceeded our expectations,” said Dr. Michael T. Flavin, Chief Executive Officer for Advanced Life Sciences. “We believe that Cethromycin’s unique antibacterial properties differentiate it from other antibiotics and, if approved by the FDA, may allow it to become a useful tool in the treatment of infections such as anthrax.”Cethromycin was recently granted Orphan Drug designation by the FDA for the prophylactic treatment of inhalation anthrax and is being developed in collaboration with U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) and the NIH’s National Institute of Allergy and Infectious Disease (NIAID). Cethromycin, which has been tested in over 4,400 human subjects, is also in pivotal Phase III trials for the treatment of community acquired pneumonia (CAP). The Company expects to report data from the CAP program in June of this year.”With emerging bacterial resistance, both natural and engineered, there is a critical need for new antibiotics that work differently than currently available therapies to protect against anthrax,” continued Dr. Flavin. “To our knowledge, there are no other antibiotics in late-stage development to address this need. Based on the human safety and animal efficacy data collected to date, we believe that Cethromycin could address this need and be considered for purchase by the U.S. Government under Project BioShield and the Strategic National Stockpile to provide protection to the American public in the event of an anthrax attack.”Primate Study FindingsIn the study, 30 naive non-human primates were randomized into 3 groups of 10 animals and were aerosol challenged with Ames strain anthrax spores at a target dose of 50 LD50. Beginning 24 hours post-challenge, 10 primates were treated with 16 mg/kg (the human equivalent of 300 mg) Cethromycin once daily, 10 primates were treated with 16 mg/kg ciprofloxacin twice daily, and 10 primates received water for injection (2 ml/kg) once daily. All antibiotic treatments were by oral gavage for 30 days.The study results showed that all ten Cethromycin-treated animals survived, with one of the ten demonstrating abnormal hematologic parameters following antibiotic cessation, which were then normalized. One of the ten ciprofloxacin-treated animals died nine days following cessation of ciprofloxacin treatments after demonstrating clinical signs of infection, bacteremia and alterations in hematologic and coagulation parameters. All ten control primates demonstrated a combination of clinical signs of anthrax, bacteremia, and alterations in hematologic and coagulation parameters post-challenge with five of ten succumbing to the infection.(Source: Food and Drug Administration (FDA) : June 2007.)