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In the primary analysis of the phase III OlympiAD trial, olaparib significantly prolonged progression‐free survival (PFS) vs chemotherapy treatment of physician's choice (TPC) in patients with germline BRCA‐mutated (gBRCAm), HER2‐negative metastatic breast cancer (mBC). We report subgroup analyses for the final analysis at a median OS follow‐up of 18.9 months (olaparib) and 15.5 months (TPC). Patients (N = 302) with gBRCAm, HER2‐negative mBC and ≤2 previous lines of chemotherapy for mBC were randomized 2:1 to open‐label olaparib (300 mg twice daily) or TPC. All subgroup analyses were prespecified except site of metastases. Investigator‐assessed median PFS was 8.0 months (95% confidence interval [CI] 5.8‐8.4; 176/205 events) for olaparib and 3.8 months (95% CI 2.8‐4.2; 83/97 events) for TPC (hazard ratio 0.51, 95% CI 0.39‐0.66). In subgroup analyses, median PFS hazard ratios (95% CI) favored olaparib: hormone receptor status (triple‐negative: 0.47, 0.32‐0.69; hormone receptor‐positive: 0.52, 0.36‐0.75); gBRCAm (BRCA1: 0.49, 0.35‐0.71; BRCA2: 0.49, 0.33‐0.74); site of metastases (visceral/CNS: 0.53, 0.40‐0.71; non‐visceral: 0.45, 0.23‐0.98); prior chemotherapy for mBC (yes: 0.51, 0.38‐0.70; no: 0.49, 0.30‐0.82); prior platinum‐based chemotherapy for BC (yes: 0.49, 0.30‐0.83; no: 0.50, 0.37‐0.69); progressive disease at randomization (yes: 0.48, 0.35‐0.65; no: 0.61, 0.36‐1.07). Investigator‐assessed objective response rates were higher across all subgroups with olaparib (35‐68%) vs TPC (5‐40%). Global health status/health‐related quality of life increased in all subgroups with olaparib vs decreased/no change with TPC. These data confirm the consistency of olaparib benefit across patient subgroups in OlympiAD. [ABSTRACT FROM AUTHOR]

Background: Maintenance treatment with the oral poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor olaparib (Lynparza) in Study 19 (study number, D0810C00019; ClinicalTrials.gov identifier, NCT00753545) significantly improved progression-free survival in comparison with a placebo for patients with platinum-sensitive, relapsed serous ovarian cancer with a BRCA1/2 mutation (BRCAm), but an interim analysis revealed no statistically significant overall survival (OS) benefit. However, 23% of the patients receiving the placebo switched to a PARP inhibitor after progression. To investigate whether this had a confounding effect on OS, this article reports an exploratory post hoc analysis that excluded all patients from sites where 1 or more placebo patients received postprogression PARP inhibitor treatment.Methods: In Study 19, 136 of the 265 patients receiving olaparib or a placebo had a BRCAm. Sixteen patients treated at 11 of the 82 investigational sites received a PARP inhibitor after progression; these sites were excluded from this analysis, and 97 BRCAm patients at 50 sites were included. OS was assessed with a Cox proportional hazards model analogous to the primary study analysis. A supporting rank-preserving structural failure time (RPSFT) model analysis was undertaken for all 136 BRCAm patients.Results: The OS hazard ratio (HR) was 0.52 (95% confidence interval [CI], 0.28-0.97) for the 97 BRCAm patients, whereas for the interim OS analysis with all 136 BRCAm patients, it was 0.73 (95% CI, 0.45-1.17). The supportive RPSFT analysis HR was approximately 0.66.Conclusions: The numerical improvement in the OS HR suggests that in Study 19, postprogression PARP inhibitor treatment had a confounding influence on the interim OS analysis for BRCAm patients. There is a degree of uncertainty due to the small sample size and the lack of data maturity. Cancer 2016;122:1844-52. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]

Voriconazole is a new triazole antifungal agent, and is metabolized by the cytochrome P450 isoenzymes CYP2C9, CYP2C19, and, to a lesser extent, by CYP3A4. Phenytoin is an inducer of CYP3A4 activity, and a substrate and inducer of CYP2C9 and CYP2C19. The present studies investigated the pharmacokinetic interactions of voriconazole and phenytoin when coadministered. Two placebo-controlled parallel-group studies were conducted in healthy male volunteers. Study A was an open-label study and investigated the effect of phenytoin (300 mg once daily) on the steady-state pharmacokinetics of voriconazole (200 mg and 400 mg twice daily). Study B was a double-blind randomized study to investigate the effects of voriconazole (400 mg twice daily) on the steady-state pharmacokinetics of phenytoin (300 mg once daily). Cmax and AUCτ were compared at days 7, 21, and 28 (Study A), and at days 7 and 17 (Study B). All adverse events were recorded. Study A: 21 subjects were evaluable (10 voriconazole + phenytoin, 11 voriconazole + placebo). For subjects receiving voriconazole (200 mg twice daily) plus phenytoin, the day 21/day 7 ratios for voriconazole Cmax and AUCτ were 60.7%[90% confidence interval (CI) 50.1, 73.6] and 35.9% (90% CI 29.7, 43.3), respectively. Adjusted for voriconazole + placebo, the ratios between the means were 50.7% (90% CI 38.8, 66.1) and 30.6% (90% CI 23.5, 39.7), respectively. When the dose of voriconazole was increased to 400 mg twice daily, the day 28/day 7 ratios for voriconazole Cmax and AUCτ were 134% (90% CI 89.2, 200) and 139% (90% CI 97.3, 199), respectively. Study B: 15 subjects were evaluable for pharmacokinetic assessments (six phenytoin + voriconazole, nine phenytoin + placebo). The ratios between the means for phenytoin + voriconazole/phenytoin + placebo on day 17 vs. day 7 were: phenytoin Cmax 167% (90% CI 144, 193) and phenytoin AUCτ 181% (90% CI 156, 210). All treatments were well tolerated: most adverse events were mild/moderate and transient. Repeat dose administration of phenytoin decreased the mean steady-state Cmax and AUCτ of voriconazole by approximately 50% and 70%, respectively. Increasing the dose of voriconazole from 200 mg to 400 mg b.d. compensated for this effect. Repeat dose administration of 400 mg b.d. voriconazole increased the mean steady-state Cmax and AUCτ of phenytoin by approximately 70% and 80%, respectively. It is therefore recommended that plasma phenytoin concentrations are monitored and the dose adjusted as appropriate when phenytoin is coadministered with voriconazole. [ABSTRACT FROM AUTHOR]

Investigates the effect of the antiretroviral protease inhibitors saquinovir and ritonavir on the pharmacokinetic properties and tolerability of sildenafil. Effect of sildenafil on the steady-state pharmacokinetics of saquinovir and ritonavir; Indication that both saquinovir and ritonavir modify the pharmacokinetics of sildenafil presumably through inhibition of cytochrome P450 3A4.