Sotrastaurin in calcineurin inhibitor-free regimen using everolimus in de novo kidney transplant recipients.

Sotrastaurin, a novel selective protein-kinase-C inhibitor, inhibits early T cell activation via a calcineurin-independent pathway. Efficacy and safety of sotrastaurin in a calcineurin inhibitor-free regimen were evaluated in this two-stage Phase II study of de novo kidney transplant recipients. Stage 1 randomized 131 patients (2:1) to sotrastaurin 300 mg or cyclosporine A (CsA). Stage 2 randomized 180 patients (1:1:1) to sotrastaurin 300 or 200 mg or CsA. All patients received basiliximab, everolimus (EVR) and prednisone. Primary endpoint was composite efficacy failure rate of treated biopsy-proven acute rejection, graft loss, death or lost to follow-up. Main safety assessment was estimated glomerular filtration rate (eGFR) by MDRD-4 at Month 12. Composite efficacy failure rates at 12 months were higher in sotrastaurin arms (Stage 1: 16.5% and 10.9% for sotrastaurin 300 mg and CsA; Stage 2: 27.2%, 34.5% and 19.4% for sotrastaurin 200 mg, 300 mg and CsA). eGFR was significantly better in sotrastaurin groups versus CsA at most time points, except at 12 months. Gastrointestinal and cardiac adverse events were more frequent with sotrastaurin. Higher treatment discontinuation, deaths and graft losses occurred with sotrastaurin 300 mg. Sotrastaurin combined with EVR showed higher efficacy failure rates and some improvement in renal allograft function compared to a CsA-based therapy.

N-terminal region of the PB1-F2 protein is responsible for increased expression of influenza A viral protein PB1.

Influenza A virus (IAV) PB1-F2 protein is encoded by an alternative reading frame (+1) within the PB1 gene. PB1-F2 has been shown to contribute to the pathogenesis of influenza virus infection as well as to the secondary bacterial infection. More recently has been shown that PB1-F2 protein may regulate a viral RNA (vRNA) polymerase activity by the interaction with PB1 protein. We proved that PB1-F2 protein increased the level of expression of PB1 protein and vRNA in the infected cells. Moreover, we demonstrated that a higher level of vRNA expression resulted in the increase of expression of multiple viral proteins, including NP, M1, and NS1. Finally, we used plasmids expressing N-terminal (1-50 aa) or C-terminal (51-87 aa) region of the PB1-F2 molecule for transfection of MDCK cells co-infected with influenza A/Puerto Rico/8/34 (H1N1) virus deficient in the PB1-F2 protein expression (PR8ΔPB1-F2). These experiments clearly showed that N-terminal region of PB1-F2 protein was responsible for the increase in PB1 protein expression. C-terminal region of PB1-F2 protein had no effect. Thus, we have identified the important function for N-terminal region of PB1-F2 protein.