CanSino Biologics Inc. announced that it has obtained clinical trial approval granted by the National Medical Products Administration of the People's Republic of China to initiate relevant clinical trials for the Haemophilus Influenzae Type b (the Hi) Conjugate Vaccine, Freeze-dried (the Hib) a vaccine candidate developed by the Company. As a gram-negative bacillus, haemophilus influenzae is one of the most prevalent pathogens of acute lower respiratory tract infections in children, and is classified into encapsulated and unencapsulated strains, both of which can induce infections. The unencapsulated strain often causes diseases like otitis media and sinusitis, which is mainly due to the spread of colonising bacteria from the nasopharynx to neighbouring areas; infections secondary to bloodstream invasion are usually caused by the encapsulated strains.

Encapsulated strains are classified according to the chemical composition of the capsular polysaccharide, and 6 serotypes have been identified, of which about 95% of invasive haemophilus influenzai disease is caused by type b. The Hib Vaccine is a covalent combination of purified Hib capsular polysaccharide and tetanus toxoid protein in a freeze-dried dosage, which is expected to induce humoral immunity against Hib after vaccination and provide protection to the vaccinees.