Pfizer begins Phase 2b study of S. aureus vaccine in adults undergoing elective spinal fusion surgery

The first patients have been enrolled in a Phase 2b clinical trial of Pfizer’s investigational Staphylococcus aureus (S. aureus) multi-antigen vaccine (PF-06290510) in adults undergoing elective spinal fusion surgery.

The purpose of the study, named STRIVE, is to evaluate the safety and efficacy of the vaccine to determine if it prevents postoperative invasive S. aureus infections in patients undergoing elective spinal surgery.

Surgical Site Infections (SSIs) are a significant and growing concern. SSIs caused by S. aureus account for approximately 20% of all SSIs in the US alone. Patients who suffer such infections due to antibiotic resistant (MRSA) or antibiotic sensitive (MSSA) S. aureus have worse clinical outcomes, including increased mortality in comparison with non-infected patients.

No licensed vaccine currently available to prevent invasive S. aureus disease

“We are pleased to take this important next step in the development of our S. aureus vaccine,” said Dr Kathrin Jansen, senior vice president and chief scientific officer of Vaccine Research and Development for Pfizer. “To date, there is no licensed vaccine available to prevent invasive S. aureus disease. We believe results from this study, if positive, will bring us closer to a potential preventive measure for this challenging disease that is associated with considerable morbidity and mortality.”

The primary outcome of the study, with an estimated enrollment of 2600 subjects, will measure the number of subjects in each treatment group with postoperative S. aureus blood stream infections and/or deep incisional or organ/space surgical site infections occurring within 90 days after elective posterior instrumented lumbar spinal fusion. Secondary outcomes will also measure postoperative S. aureus blood stream infections and/or deep incisional or organ/space surgical site infections occurring within 180 days after surgery, and postoperative S. aureus surgical site infections occurring within 90 and 180 days after elective posterior instrumented lumbar spinal fusion. Estimated completion of the study is 2017.