Predicting the artificial immunity induced by RUTI® vaccine against tuberculosis using universal immune system simulator (UISS).

BACKGROUND: Tuberculosis (TB) represents a worldwide cause of mortality (it infects one third of the world's population) affecting mostly developing countries, including India, and recently also developed ones due to the increased mobility of the world population and the evolution of different new bacterial strains capable to provoke multi-drug resistance phenomena. Currently, antitubercular drugs are unable to eradicate subpopulations of Mycobacterium tuberculosis (MTB) bacilli and therapeutic vaccinations have been postulated to overcome some of the critical issues related to the increase of drug-resistant forms and the difficult clinical and public health management of tuberculosis patients. The Horizon 2020 EC funded project "In Silico Trial for Tuberculosis Vaccine Development" (STriTuVaD) to support the identification of new therapeutic interventions against tuberculosis through novel in silico modelling of human immune responses to disease and vaccines, thereby drastically reduce the cost of clinical trials in this critical sector of public healthcare. RESULTS: We present the application of the Universal Immune System Simulator (UISS) computational modeling infrastructure as a disease model for TB. The model is capable to simulate the main features and dynamics of the immune system activities i.e., the artificial immunity induced by RUTI® vaccine, a polyantigenic liposomal therapeutic vaccine made of fragments of Mycobacterium tuberculosis cells (FCMtb). Based on the available data coming from phase II Clinical Trial in subjects with latent tuberculosis infection treated with RUTI® and isoniazid, we generated simulation scenarios through validated data in order to tune UISS accordingly to STriTuVaD objectives. The first case simulates the establishment of MTB latent chronic infection with some typical granuloma formation; the second scenario deals with a reactivation phase during latent chronic infection; the third represents the latent chronic disease infection scenario during RUTI® vaccine administration. CONCLUSIONS: The application of this computational modeling strategy helpfully contributes to simulate those mechanisms involved in the early stages and in the progression of tuberculosis infection and to predict how specific therapeutical strategies will act in this scenario. In view of these results, UISS owns the capacity to open the door for a prompt integration of in silico methods within the pipeline of clinical trials, supporting and guiding the testing of treatments in patients affected by tuberculosis.

RUTI Vaccination Enhances Inhibition of Mycobacterial Growth ex vivo and Induces a Shift of Monocyte Phenotype in Mice.

Tuberculosis (TB) is a major global health problem and there is a dire need for an improved treatment. A strategy to combine vaccination with drug treatment, termed therapeutic vaccination, is expected to provide benefit in shortening treatment duration and augmenting treatment success rate. RUTI candidate vaccine has been specifically developed as a therapeutic vaccine for TB. The vaccine is shown to reduce bacillary load when administered after chemotherapy in murine and guinea pig models, and is also immunogenic when given to healthy adults and individuals with latent TB. In the absence of a validated correlate of vaccine-induced protection for TB vaccine testing, mycobacterial growth inhibition assay (MGIA) has been developed as a comprehensive tool to evaluate vaccine potency ex vivo. In this study, we investigated the potential of RUTI vaccine to control mycobacterial growth ex vivo and demonstrated the capacity of MGIA to aid the identification of essential immune mechanism. We found an association between the peak response of vaccine-induced growth inhibition and a shift in monocyte phenotype following RUTI vaccination in healthy mice. The vaccination significantly increased the frequency of non-classical Ly6C- monocytes in the spleen after two doses of RUTI. Furthermore, mRNA expressions of Ly6C--related transcripts (Nr4a1, Itgax, Pparg, Bcl2) were upregulated at the peak vaccine response. This is the first time the impact of RUTI has been assessed on monocyte phenotype. Given that non-classical Ly6C- monocytes are considered to play an anti-inflammatory role, our findings in conjunction with previous studies have demonstrated that RUTI could induce a balanced immune response, promoting an effective cell-mediated response whilst at the same time limiting excessive inflammation. On the other hand, the impact of RUTI on non-classical monocytes could also reflect its impact on trained innate immunity which warrants further investigation. In summary, we have demonstrated a novel mechanism of action of the RUTI vaccine, which suggests the importance of a balanced M1/M2 monocyte function in controlling mycobacterial infection. The MGIA could be used as a screening tool for therapeutic TB vaccine candidates and may aid the development of therapeutic vaccination regimens for TB in the near future.

Safety, tolerability, and immunogenicity of the novel antituberculous vaccine RUTI: randomized, placebo-controlled phase II clinical trial in patients with latent tuberculosis infection.

OBJECTIVES: To evaluate the safety, tolerability and immunogenicity of three different doses (5, 25 and 50 µg) of the novel antituberculous vaccine RUTI compared to placebo in subjects with latent tuberculosis infection. METHODS AND FINDINGS: Double-blind, randomized, placebo-controlled Phase II Clinical Trial (95 patients randomized). Three different RUTI doses and placebo were tested, randomized both in HIV-positive (n = 47) and HIV-negative subjects (n = 48), after completion of one month isoniazid (INH) pre-vaccination. Each subject received two vaccine administrations, 28 Days apart. Five patients withdrew and 90 patients completed the study. Assessment of safety showed no deaths during study. Two subjects had serious adverse events one had a retinal detachment while taking INH and was not randomized and the other had a severe local injection site abscess on each arm and was hospitalized; causality was assessed as very likely and by the end of the study the outcome had resolved. All the patients except 5 (21%) patients of the placebo group (3 HIV+ and 2 HIV-) reported at least one adverse event (AE) during the study. The most frequently occurring AEs among RUTI recipients were (% in HIV+/-): injection site reactions [erythema (91/92), induration (94/92), local nodules (46/25), local pain (66/75), sterile abscess (6/6), swelling (74/83), ulcer (20/11), headache (17/22) and nasopharyngitis (20/5)]. These events were mostly mild and well tolerated. Overall, a polyantigenic response was observed, which differed by HIV- status. The best polyantigenic response was obtained when administrating 25 µg RUTI, especially in HIV-positive subjects which was not increased after the second inoculation. CONCLUSION: This Phase II clinical trial demonstrates reasonable tolerability of RUTI. The immunogenicity profile of RUTI vaccine in LTBI subjects, even being variable among groups, allows us considering one single injection of one of the highest doses in future trials, preceded by an extended safety clinical phase. TRIAL REGISTRATION: ClinicalTrials.gov NCT01136161.

Racemic and chiral sulfoxides as potential prodrugs of 4-pyrone COX-2 inhibitors.

The preparation of the sulfoxide analogues 7, 8, and 9 and their enantiomerically pure forms is discussed as well as their ability to act as prodrugs of the potent and selective sulfone-containing COX-2 inhibitors 1, 2, and 3. Sulfoxide derivatives 7 and 9 were shown to be rapidly transformed in vivo into the corresponding sulfone derivatives 1 and 3, after oral administration to rats.

Racemic and chiral sulfoxides as potential prodrugs of the COX-2 inhibitors Vioxx and Arcoxia.

The preparation of the sulfoxide analogues 2 and 4, and their enantiomeric pure forms is discussed as well as their potential to act as prodrugs to the potent and selective sulfone-containing COX-2 inhibitors rofecoxib and etoricoxib. Sulfoxides 2 and 4 were shown to be effectively transformed in vivo into rofecoxib and etoricoxib, respectively, after oral administration in rats. In the case of sulfoxide 2, both a slightly improved pharmacokinetic profile and a better pharmacological activity in an arthritis model were seen when compared with rofecoxib.

Synthesis and biological evaluation of 2-phenylpyran-4-ones: a new class of orally active cyclooxygenase-2 inhibitors.

A series of 2-phenylpyran-4-ones were prepared and evaluated for their ability to inhibit cyclooxygenase-2 (COX-2). Extensive structure-activity relationship work was carried out within this series, and a number of potent and selective COX-2 inhibitors were identified. Compounds having a p-methylsulfone group at the 2-phenyl ring showed the best COX-2 inhibitory activity. The introduction of a substituted phenoxy ring at position 3 enhanced both the in vitro and in vivo activity within the series. A selected group of 3-phenoxypyran-4-ones exhibited excellent activity in an experimental model of pyresis. The in vivo antiinflammatory activity of these compounds was confirmed with the evaluation of their antiarthritic and analgesic effectiveness. Moreover, their pharmacokinetic profile in rats is compatible with a once a day administration by oral route in humans. Within this novel series, compounds 21, 31, 34, and 35 have been selected for further preclinical and clinical evaluation.

Amide derivatives of [5-chloro-6-(2-chloro/fluorobenzoyl)-2-benzoxazolinone-3-yl]acetic acids as potential analgesic and anti-inflammatory compounds.

In this study, we have explored the prevention of gastric side effects such as gastric lesions and bleeding while maintaining the high analgesic and anti-inflammatory activities by the derivatization of the carboxylate moiety into amides in [5-chloro-6-(2-chloro/fluorobenzoyl)-2-benzoxazolinone-3-yl]acetic acids. We have tested the analgesic and anti-inflammatory activities of the synthesized compounds in vivo by using p-benzoquinone-induced writhing test and carrageenan-induced hind paw edema model, respectively. Compounds 3a, 3d, 3e, 3j and 3k potent analgesic and anti-inflammatory activities without gastric lesions in the tested animals. Therefore, conversion of the carboxylate moiety into certain amide derivatives generated potent analgesic and anti-inflammatory compounds while eliminating the gastrointestinal side effects. Cyclooxygenase (COX)-selectivity of the active compounds was also investigated by using in vitro human whole blood assay. Compounds 3a, 3e, 3h and 3k selective inhibition of COX-2 to some extent although the inhibitory activity was not very potent.