Cystic Fibrosis (CF) is an autosomal recessive disorder caused by genetic mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein. This leads to numerous medical problems including abnormal airway secretions, mucus accumulation, and opportunistic bacterial infections. Pseudomonas aeruginosa is the most significant pathogen, with >80% of CF patients becoming chronically infected with P. aeruginosa by 18 years of life. Antibiotics treatments can and have lead to selection of resistant organisms, which are less responsive to drug treatments and worsen disease progression.

Despite being prescribed with different antibiotic treatment regimens, almost all of CF patients ultimately succumb to respiratory failure due to chronic P. aeruginosa infection and airway inflammation.

Aridis' (Panaecin^TM) is a promising therapeutic option to control chronic lung infections whose benefits are differentiated from current standard of care antibitotics used in CF. Panaecin's differentiation factors include: broad bactericidal activities against gram negative and gram positive bacteria, including difficult to treat staph. aureus and burkholdaria cepacia, effective under drug resistant bacterial biofilms conditions, and augmentation of the natural immune response mediated by lactoferrin and transferrin.

In contrast to traditional antibiotics approach, Aridis’ (Aerucin^TM) human monoclonal antibody is an immunological approach that works by enhancing the immune system’s ability to fight the infections. This novel approach is less susceptable to development of antibiotic resistance, can be used both therapeutically and prophylactically, and potentially can be used with greatly diminished dose frequency as compared to current antibiotics used in CF, which are administered daily 2-3 times per day.

CF Foundation Annual Report 2005

CF patients can be treated therapeutically by Panaecin and Aerucin, alone or in combination with other existing antibiotics. Additionally, Aerucin can be used prophylactically to prevent initial lung infection with P. aeruginosa in younger and less severe patients. The potential market for Aridis' anti-infective drug candidates includes all CF patients in the US (~30,000) and Europe (~30,000). Current products provide temporary lung function improvement, only incremental long term impact on lung deterioration, yet have aggregate annual sales of nearly $600 MM. Our product candidates are expected to have annual sales comparable to or larger than the existing therapies.