Dose-Finding Quantitative 18F-FDG PET Imaging Study with the Oral Pan-AKT Inhibitor GSK2141795 in Patients with Gynecologic Malignancies.

UNLABELLED: AKT (a serine/threonine-specific protein kinase) regulates many cellular processes contributing to cytotoxic drug resistance. This study's primary objective examined the relationship between GSK2141795, an oral, pan-AKT inhibitor, and (18)F-FDG PET markers of glucose metabolism in tumor tissue to determine whether (18)F-FDG PET could be used to guide personalized dosing of GSK2141795. Biomarker analysis of biopsies was also undertaken. METHODS: Twelve patients were enrolled in 3 cohorts; all underwent dynamic (18)F-FDG PET scans and serial pharmacokinetic sampling at baseline, week 2, and week 4 with tumor biopsies before treatment and at week 4. Response was evaluated by RECIST v1.1 and Gynecologic Cancer Intergroup criteria. Biopsy samples were analyzed for mutations and protein expression. RESULTS: GSK2141795 did not significantly influence blood glucose levels. No dose-response relationship was observed between GSK2141795 pharmacokinetics and (18)F-FDG PET pharmacodynamic measures; however, an exposure-response relationship was seen between maximum drug concentrations and maximal decrease in (18)F-FDG uptake in the best-responding tumor. This relationship also held for pharmacokinetic parameters of exposure and 1,5-anhydroglucitol (a systemic measure of glucose metabolism). Phospho-AKT upregulation at week 4 in biopsies confirmed AKT inhibition by GSK2141795. Single-agent activity was observed with a clinical benefit rate of 27% (3/11) and 30% (3/10) CA125 response in the study's platinum-resistant ovarian patients. AKT pathway activation by PIK3CA/PIK3R1 mutation did not correlate with clinical activity, whereas RAS/RAF pathway mutations did segregate with resistance to AKT inhibition. CONCLUSION: GSK2141795 demonstrated an exposure-response relationship with decreased (18)F-FDG uptake and is active and tolerable. This study's design integrating (18)F-FDG PET, pharmacokinetics, and biomarker analyses demonstrates the potential for clinical development for personalized treatment.

Once-daily versus twice-daily lamivudine, in combination with zidovudine and efavirenz, for the treatment of antiretroviral-naive adults with HIV infection: a randomized equivalence trial.

A randomized, double-blind, double-dummy controlled, multicenter trial was conducted that involved 554 antiretroviral-naive human immunodeficiency virus-infected adults (plasma HIV type 1 [HIV-1] RNA level, >or=400 copies/mL; CD4(+) cell count, >100 cells/mm(3)) and compared a 300-mg once-daily (q.d.) regimen of lamivudine (3TC) versus a 150-mg twice-daily (b.i.d.) regimen of 3TC, combined with zidovudine (300 mg b.i.d.) and efavirenz (600 mg q.d.), during a 48-week period. Treatments were considered equivalent if the 95% confidence interval (CI) for the difference in proportions of patients achieving an HIV-1 RNA level of <400 copies/mL was within the bound of -12% to 12%. At week 48 of the study, an intent-to-treat analysis in which patients with missing data were considered to have experienced treatment failure showed that the 3TC q.d. and 3TC b.i.d. regimens were equivalent (HIV-1 RNA level <400 copies/mL, 178 [64%] of 278 vs. 174 [63%] of 276; treatment difference, 1% [95% CI, -7.1% to 8.9%]; HIV-1 RNA level <50 copies/mL, 165 [59%] of 278 vs. 168 [61%] of 276; treatment difference, 1.7% [95% CI, -9.7% to 6.6%]). Median increase above baseline in CD4(+) cell count was similar (q.d. group, +144 cells/mm(3); b.i.d. group, +146 cells/mm(3)), and the incidences of adverse events, disease progression, and HIV-associated conditions were comparable.