Nabi Biopharmaceuticals' US immunogenicity study for StaphVAX (Staphylococcus aureus Polysaccharide Conjugate Vaccine) in patients undergoing orthopedic surgery with a prosthetic device implant attained positive results. Orthopedic patients are an at-risk group for S. aureus infections in conjunction with their surgery.

The study demonstrated that 94 per cent of patients achieved antibody levels above the estimated protective levels. This compares favorably to the 80 per cent of immunocompromised end-stage renal disease (ESRD) patients who achieved similar protective levels, as previously reported. Antibody levels observed in the current study are also consistent with the levels achieved in patients undergoing cardiovascular surgery, states a company release

StaphVAX is being developed to prevent S. aureus infections in at-risk patients. This includes patients on dialysis, patients undergoing cardiovascular, orthopedic and other surgeries, immunocompromised patients such as the elderly, diabetics, cancer patients undergoing chemotherapy, and patients who have previously been treated for S. aureus infections.