Efficacy and pharmacokinetics of intravenous paracetamol in the critically ill patient

Introduction: Paracetamol (PCM) is a drug with analgesic and antipyretic properties. Despite its frequent use, little is known about its efficacy and pharmacokinetics (PK) when intravenously administered in the critically ill patient. A previous study suggests that therapeutic concentrations are not always reached [1]. The primary aim of this open-label, multiple-dose study was to evaluate intravenous PCM therapy in critically ill, secondary aim was to study the PK of intravenous PCM. Methods: Ventilated patients needing PCM treatment according to our ICU protocol (1 g PCM intravenously four times daily) were eligible for inclusion. Excluded were those with severe liver failure and those treated with PCM on the time of admission to the ICU. Blood samples were collected at 0, 30, 60, 180 and 300 minutes after the first and, if possible, the fifth and 21st doses. A computerized model was used to estimate population PK. Results: Nineteen patients were included of which 13 were male, with a mean APACHE IV score of 94.8. No antipyretic effect could be measured in any of the patients. PK parameters have been calculated for all patients after the first PCM dose. The half-life was 2.2 hours, the volume of distribution was 1.03 l/kg, and the clearance was 0.33 l/kg/hour. Data from 15 patients could be analysed after the fifth dose and from five patients after the 21st dose. The PK of intravenous PCM in our population show a biphasic profile (Figure 1). One hour after the dose, the mean serum concentration level was below the therapeutic level. In 18 out of 19 patients serum concentration dropped below 5 mg/ml before the next dose, resulting in a lack of build-up of a suitable therapeutic level of PCM after multiple dosages. Conclusions: The recommended dose of 1 g intravenous PCM four times daily is not sufficient to achieve a therapeutic effect in critically ill patients. This can be explained by the low serum levels reached. These results warrant the development of an adequate dosing scheme for intravenous PCM followed by a large clinical trial studying the effects and safety of this regimen in critically ill patients

Immunization with a P53 synthetic long peptide vaccine induces P53-specific immune responses in ovarian cancer patients, a phase II trial.

The prognosis of ovarian cancer, the primary cause of death from gynecological malignancies, has only modestly improved over the last decades. Immunotherapy is one of the new treatment modalities explored for this disease. To investigate safety, tolerability, immunogenicity and obtain an impression of clinical activity of a p53 synthetic long peptide (p53-SLP) vaccine, twenty patients with recurrent elevation of CA-125 were included, eighteen of whom were immunized 4 times with 10 overlapping p53-SLP in Montanide ISA51. The first 5 patients were extensively monitored for toxicity, but showed no > or = grade 3 toxicity, thus accrual was continued. Overall, toxicity was limited to grade 1 and 2, mostly locoregional, inflammatory reactions. IFN-gamma producing p53-specific T-cell responses were induced in all patients who received all 4 immunizations as measured by IFN-gamma ELISPOT. An IFN-gamma secretion assay showed that vaccine-induced p53-specific T-cells were CD4(+), produced both Th1 and Th2 cytokines as analyzed by cytokine bead array. Notably, Th2 cytokines dominated the p53-specific response. P53-specific T-cells were present in a biopsy of the last immunization site of at least 9/17 (53%) patients, reflecting the migratory capacity of p53-specific T-cells. As best clinical response, stable disease evaluated by CA-125 levels and CT-scans, was observed in 2/20 (10%) patients, but no relationship was found with vaccine-induced immunity. This study shows that the p53-SLP vaccine is safe, well tolerated and induces p53-specific T-cell responses in ovarian cancer patients. Upcoming trials will focus on improving T helper-1 polarization and clinical efficacy