A recent publication [1] from the team which brought us the Meningococcal B vaccine is of interest from the perspective of vaccine development strategy and feasibility.
Appropriately, tuberculosis (TB) leads the list of important bacterial targets for vaccine research. Despite numerous attempts, all the vaccines candidate tested so far had insufficient efficacy in clinical trials. Many parts of the world still have to rely on the immune stimulation provided by the old BCG vaccine which – by the way – provides incomplete protection and can have significant local and systemic side effects.
The authors summarize the disappointing experience with so many S. aureus vaccines which turned out to be failures. It seems that opsonizing antibodies are just not sufficient to prevent disease; T-cell mediated immunity is probably much more important for controlling this pathogen than previously considered [2]. Several antibody-based approaches were unsuccessful, including a recent trial with the V710 vaccine directed against IsdB.
Travelers are exposed to many illnesses for which vaccines are either not available or not very effective. There is a growing need for protection against Shigella and ETEC, both toxin-mediated diseases which have many similarities. Clearly, the efficacy of the existing Cholera vaccine is suboptimal.
Although not discussed in the article, an accompanying table shows that the researchers also have vaccines directed against Klebsiella and Pseudomonas on their radar. A Pseudomonas vaccine is in Phase 2 at Novartis, in collaboration with Intercell. This is the partnership that brought us a vaccine for Japanese encephalitis (Ixiaro) a few years ago.
There is also a joint effort with Intercell to work on a vaccine against C. difficile. This nicely complements the in-house LFF-571 program, a novel MoA compound (elongation factor inhibitor) which seems to have finished Phase 2 testing. Somewhat surprisingly, the compound is not included in the Novartis drug pipeline chart [3] . Probably just an oversight…
References:
[1] Delany. Vaccines for the 21st century EMBO Mol Med. 2014; 6:708
[2] Joshi. Developing a universal S. aureus vaccine: Why aren’t we there yet? Intern. Med. 2013; 3: 2
[3] http://www.novartis.com/innovation/research-development/clinical-pipeline/index.shtml
