Monday, July 07, 2008

Ceftobiprole To The Rescue

ResearchBlogging.orgBack when I was a Medical Technologist, and doing my microbiology clinical rotations, the lab director who was supervising me sat me down several times a week. During these sit downs, we went over various microbiological topics. One such topic was antibiotic resistance. I remember him quite clearly when he told me that if vancomycin-resistant organisms ever arose, we'd all be in deep poop. Well, there are organisms out there which are now vancomycin resistant. Why is this such a problem? Vancomycin is literally the last line of defense. It is the antibiotic which is given when no others are left to treat a bacterial infection. If this drug doesn't work ... there are no other alternatives.

Or at least there were no other options, until Ceftobiprole (BPR) came along. I honestly can't believe this hasn't made as big a splash in the science blogging community as it should have. Science Daily does have an article on it though. So far in lab tests, Ceftobiprole has an excellent kill-rate. More importantly, it is very effective against organisms which are multiple-drug resistant.
In an ominous new "move" in this chess game, S. aureus strains with resistance to vancomycin (VRSA), a different class of antibiotics, also began to appear in hospitals in the United States. Ceftobiprole was also able to kill these new resistant VRSA strains.
This is excellent news.

So how does it work? It binds to the penicillin-binding protein PBP2a, product of the antibiotic resistance gene mecA. Studies examining penicillin-resistant strains of S. aureus treated with non-lethal (for the bacteria) doses of BPR revealed that these organisms displayed profiles which were similar to non-penicillin-resistant strains of S. aureus which were treated with penicillin. Beta-lactams are a class of antibiotics which inhibit cell-wall synthesis.
Bacteria grown in the presence of sub-MIC concentrations of BPR produced an HPLC profile characteristic of β-lactam-treated staphylococci ...
At least for me, this is an exciting development. This potentially adds an additional drug into the arsenal of infectious disease doctors who have to treat multiple-drug resistance bacteria. It also opens up a whole new line of targets for future antibiotics.

Chung, M., Antignac, A., Kim, C., Tomasz, A. (2008). Comparative study of the susceptibility of major epidemic clones of MRSA to oxacillin and to the new broad spectrum cephalosporin ceftobiprole. Antimicrobial Agents and Chemotherapy DOI: 10.1128/AAC.00266-08

1 comment:

Pete said...

Whilst I agree that ceftobiprole is likely to garner high sales it isn't the only product available for the treatment of VRSA. We already have Cubicin (daptomycin) and a few others that are pretty expensive.