In vivo genotoxicity assessment of N-(-9 acridinyl)-b-alanine hydrochloride (S-300) using a validated Pig-a mutagenesis assay.

BACKGROUND: N-(-9 acridinyl)-b-alanine hydrochloride (S-300) is the main byproduct of red blood cell (RBC) amustaline/glutathione(GSH) pathogen reduction, currently undergoing phase III US clinical trials following successful European studies(1-3). Phosphatidylinositol glycan, class A (Pig-a) X-linked gene mutagenesis is a validated mammalian in vivo mutation assay for genotoxicity, assessed as clonal loss of glycosylphosphatidylinositol-linked CD59 cell-surface molecules on reticulocytes (RETs) and RBCs. METHODS: Male Sprague-Dawley rats received continuous infusion of S-300 up to the maximum feasible dose (240 mg/kg/day-limited by solubility and volume) for 28 days. Positive controls received a known mutagen by oral gavage on Days 1-3. Plasma levels of S-300 were assessed by HPLC before, during and after infusion. CD59-negative RBCs and RETs were enumerated in pre-dose and Day 28 samples, using a flow cytometric method. Outcome was evaluated by predetermined criteria using concurrent and historical controls. Toxicity was assessed by laboratory measures and necropsy. RESULTS: S-300 reached maximum, dose-dependent levels (3-15 µmol/L) within 2-8 h that were sustained for 672 h and undetectable 2 h after infusion. Circulating RET levels indicated a lack of hematopoietic toxicity. Necropsy revealed minimal-mild observations related to poor S-300 solubility at high concentrations. Pig-a assessment met the preset acceptability criteria and revealed no increase in mutant RBCs or RETs. CONCLUSIONS: Maximum feasible S-300 exposure of rats by continuous infusion for 28 days was not genotoxic as assessed by an Organization for Economic Cooperation and Development-compliant, mammalian, in vivo Pig-a gene mutation assay that meets the requirements of International Conference on Harmonization (ICH) S2(R1) and FDA guidances on genotoxicity testing.

Effects of atorvastatin versus other statins on fasting and postprandial C-reactive protein and lipoprotein-associated phospholipase A2 in patients with coronary heart disease versus control subjects.

The effects of atorvastatin (40 mg/day) versus placebo on fasting and postprandial plasma levels of high-sensitivity C-reactive protein (hs-CRP) and lipoprotein-associated phospholipase A2 (Lp-PLA2) were examined over 36 weeks in 84 patients who had coronary heart disease and low-density lipoprotein cholesterol levels >130 mg/dl and compared directly with the effects of fluvastatin, lovastatin, pravastatin, and simvastatin. Results were also compared with those obtained in age- and gender-matched control subjects (n = 84). Feeding increased median hs-CRP levels by 2% in patients (p = NS) and 22% in controls (p <0.01) and increased mean Lp-PLA2 values by 9% in patients (p = NS) but decreased values by 21% in controls (p <0.0001). Patients had 51% higher median hs-CRP values and 29% higher mean Lp-PLA2 values than did controls (p <0.05 for hs-CRP and Lp-PLA2) in the fasting state; however, Lp-PLA2 values were 62% higher (p <0.0001) in the fed state in patients compared with controls. Atorvastatin decreased median hs-CRP levels by 32% (p <0.01) and mean Lp-PLA2 values by 26% in patients (p <0.0001), with similar decreases in the fed state, and none of the other statins had any significant effect on these parameters. Change in Lp-PLA2 was significantly related to change in low-density lipoprotein cholesterol (p <0.01), with no significant relations with change in hs-CRP. Our data indicate greater differences in patients with coronary heart disease compared with controls in Lp-PLA2 in the fed state than in the fasting state and that atorvastatin is more effective than fluvastatin, lovastatin, pravastatin, or simvastatin for decreasing not only low-density lipoprotein cholesterol but also hs-CRP and Lp-PLA2.

Comparisons of effects of statins (atorvastatin, fluvastatin, lovastatin, pravastatin, and simvastatin) on fasting and postprandial lipoproteins in patients with coronary heart disease versus control subjects.

The effects of atorvastatin at 20, 40, and 80 mg/day on plasma lipoprotein subspecies were examined in a randomized, placebo-controlled fashion over 36 weeks in 97 patients with coronary heart disease (CHD) with low-density lipoprotein (LDL) cholesterol levels of >130 mg/dl and compared directly with the effects of fluvastatin (n = 28), pravastatin (n = 22), lovastatin (n = 24), and simvastatin (n = 25). The effects of placebo and 40 mg/day of each statin were also examined in subjects with CHD with subjects in the fasting state and in the fed state 4 hours after a meal rich in saturated fat and cholesterol and compared with results in age- and gender-matched control subjects. At all doses tested in the fasting and fed states, atorvastatin was significantly (p <0.01) more effective in lowering LDL cholesterol and non-high-density lipoprotein (HDL) cholesterol than all other statins, and significantly (p <0.05) more effective than all statins, except for simvastatin, in lowering triglyceride and remnant lipoprotein (RLP) cholesterol. At 40 mg/day in the fasting state, atorvastatin was significantly (p <0.01) more effective than all statins, except for lovastatin and simvastatin, in lowering cholesterol levels in small LDL, and was significantly (p <0.05) more effective than all statins, except for simvastatin, in increasing cholesterol in large HDL and in lowering LDL particle numbers. Our data indicate that atorvastatin was the most effective statin tested in lowering cholesterol in LDL, non-HDL, and RLP in the fasting and fed states, and getting patients with CHD to established goals, with fluvastatin, pravastatin, lovastatin, and simvastatin having about 33%, 50%, 60%, and 85% of the efficacy of atorvastatin, respectively, at the same dose in the same patients.

Effects of atorvastatin on fasting and postprandial lipoprotein subclasses in coronary heart disease patients versus control subjects.

The effects of atorvastatin at 20, 40, and 80 mg/day on plasma lipoprotein subclasses were examined in a randomized, placebo-controlled fashion over 24 weeks in 103 patients in the fasting state who had coronary heart disease (CHD) with low-density lipoprotein (LDL) cholesterol levels >130 mg/dl. The effects of placebo and atorvastatin 40 mg/day were examined in 88 subjects with CHD in the fasting state and 4 hours after a meal rich in saturated fat and cholesterol. These findings were compared with results in 88 age- and gender-matched control subjects. Treatment at the 20, 40, and 80 mg/day dose levels resulted in LDL cholesterol reductions of 38%, 46%, and 52% (all p <0.0001), triglyceride reductions of 22%, 26%, and 30% (all p <0.0001), and high-density lipoprotein (HDL) cholesterol increases of 6%, 5%, and 3%, respectively (all p <0.05 at the 20- and 40-mg doses). The lowest total cholesterol/HDL cholesterol ratio was observed with the 80 mg/day dose of atorvastatin (p <0.0001 vs placebo). Remnant-like particle (RLP) cholesterol decreased 33%, 34%, and 32%, respectively (all p <0.0001). Lipoprotein(a) [Lp(a)] cholesterol decreased 9%, 16%, and 21% (all p <0.0001), although Lp(a) mass increased 9%, 8%, and 10%, respectively (all p <0.01). In the fed state, atorvastatin 40 mg/day normalized direct LDL cholesterol (29% below controls), triglycerides (8% above controls), and RLP cholesterol (10% below controls), with similar reductions in the fasting state. At this same dose level, atorvastatin treatment resulted in 39%, 35%, and 59% decreases in fasting triglyceride in large, medium, and small very LDLs, as well as 45%, 33%, and 47% reductions in cholesterol in large, medium, and small LDL, respectively, as assessed by nuclear magnetic resonance (all significant, p <0.05), normalizing these particles versus controls (77 cases vs 77 controls). Moreover, cholesterol in large HDL was increased 37% (p <0.001) by this treatment. Our data indicate that atorvastatin treatment normalizes levels of all classes of triglyceride-rich lipoproteins and LDL in both the fasting and fed states in patients with CHD compared with control subjects.