Targeting the p40 cytokines interleukin (IL)-12 and IL-23 in Crohn's disease

Bivalent non-typhoidal Salmonella outer membrane vesicles immunized mice sera confer passive protection against gastroenteritis in a suckling mice model

Invasive non-typhoidal Salmonella (iNTS) serovars, especially Salmonella Typhimurium (ST) and Salmonella Enteritidis (SE), cause gastroenteritis worldwide. Due to the emergence of multi-drug resistance in iNTS, a broad-spectrum vaccine is urgently needed for the prevention of iNTS infection. Currently, there is no effective licensed vaccine against iNTS available in the market. We have formulated an outer membrane vesicles (OMVs) based bivalent immunogen as a vaccine candidate to generate broad-spectrum protective immunity against both recently circulating prevalent ST and SE. We have isolated OMVs from ST and SE and formulated the immunogen by mixing both OMVs (1:1 ratio). Three doses of bivalent immunogen significantly induced humoral immune responses against lipopolysaccharides (LPSs) and outer membrane proteins (OMPs) as well as a cell-mediated immune response in adult mice. We also observed that proteins of OMVs act as an adjuvant for generation of high levels of anti-LPS antibodies through T cell activation. We then characterized the one-day old suckling mice model for both ST and SE mediated gastroenteritis and used the model for a passive protection study. In the passive protection study, we found the passive transfer of bivalent OMVs immunized sera significantly reduced ST and SE mediated colonization and gastroenteritis symptoms in the colon of suckling mice compared to non-immunized sera recipients. The overall study demonstrated that OMVs based bivalent vaccine could generate broad-spectrum immunity against prevalent iNTS mediated gastroenteritis. This study also established the suckling mice model as a suitable animal model for vaccine study against iNTS mediated gastroenteritis.

Briakinumab for treatment of Crohn's disease: results of a randomized trial

BACKGROUND

This study assessed the efficacy and safety of briakinumab, a human anti-IL-12/23p40 monoclonal antibody, compared with placebo for the induction and maintenance of remission in patients with moderately to severely active Crohn's disease.

METHODS

In this phase 2b, multicenter, double-blind, parallel group study, 246 patients stratified by prior tumor necrosis factor-antagonist use and response, were randomized (1:1:1:3) to 4 intravenous induction regimens: placebo, 200, 400, or 700 mg briakinumab, at weeks 0/4/8. At week 12, responders in the placebo or 400-mg induction groups entered the maintenance phase with the same regimen, whereas responders in the 700-mg induction group were rerandomized (1:1:1) to receive placebo, 200, or 700 mg briakinumab at weeks 12/16/20. At week 24, patients in remission stopped receiving study drug (withdrawal phase) until relapse. Patients experiencing relapse, nonresponders, and nonremitters could enter the open-label phase.

RESULTS

The primary end point of clinical remission at week 6 was not met. There were numerically greater rates of remission and response at 6, 12, or 24 weeks in patients treated with briakinumab. The safety and tolerability profile of briakinumab was similar in the induction and maintenance phases of the trial.

CONCLUSIONS

Briakinumab showed a similar safety and tolerability profile to placebo in the induction and maintenance phases, and comparable rates of serious adverse events, adverse events leading to discontinuation, and malignancy. These data provide support for the potential efficacy of briakinumab and other IL-12/23 inhibitors in the treatment of moderate-to-severe Crohn's disease.