Systemic Pharmacokinetics of Oxaliplatin After Intraperitoneal Administration by Electrostatic Pressurized Intraperitoneal Aerosol Chemotherapy (ePIPAC) in Patients with Unresectable Colorectal Peritoneal Metastases in the CRC-PIPAC Trial.

BACKGROUND: Electrostatic pressurized intraperitoneal aerosol chemotherapy (ePIPAC) is a palliative treatment for unresectable peritoneal metastases from various primary cancers. However, little is known about the systemic pharmacokinetics of oxaliplatin after ePIPAC. METHODS: Twenty patients with unresectable colorectal peritoneal metastases were treated with repetitive ePIPAC monotherapy with oxaliplatin (92 mg/m2) and a simultaneous intravenous bolus of leucovorin (20 mg/m2) and 5-fluorouracil (400 mg/m2). Samples were collected during each ePIPAC: whole blood at t = 0, t = 5, t = 10, t = 20, t = 30, t = 60, t = 120, t = 240, t = 360 and t = 1080 min for plasma and plasma ultrafiltrate concentrations; urine at t = 0, t = 1, t = 3, t = 5 and t = 7 days. Samples were analyzed using atomic absorption spectrometry. Pharmacokinetics were analyzed using nonlinear mixed-effects modeling. RESULTS: Four patients received one ePIPAC, three patients received two ePIPAC, and thirteen patients received ≥ 3 ePIPAC. The population pharmacokinetic models adequately described the pharmacokinetics of oxaliplatin after ePIPAC. The plasma ultrafiltrate Cmax of oxaliplatin reached 1.36-1.90 µg/mL after 30 min with an AUC0-24 h of 9.6-11.7 µg/mL * h. The plasma Cmax reached 2.67-3.28 µg/mL after 90 min with an AUC0-24 h of 49.0-59.5 µg/mL * h. The absorption rate constant (Ka) was 1.13/h. Urine concentrations of oxaliplatin rapidly decreased to less than 3.60 µg/mL in 90% of the samples at day 7. DISCUSSION: Systemic exposure to oxaliplatin after ePIPAC seemed comparable to that after systemic chemotherapy, as described in other literature. Since this is an indirect comparison, future research should focus on the direct comparison between the systemic exposure to oxaliplatin after ePIPAC and after systemic chemotherapy. TRIAL REGISTRATION: NCT03246321, Pre-results; ISRCTN89947480, Pre-results; NTR6603, Pre-results; EudraCT: 2017-000927-29, Pre-results.

Tunable secondary dimension selectivity in comprehensive two-dimensional gas chromatography.

In this paper two tunable two-dimensional gas chromatography setups are compared and described in which the secondary dimension consists of two different capillary columns coupled in series. In the first setup the selectivity of the second dimension can be tuned by adjusting the effective column length of the first secondary dimension column, simply by sliding it stepwise back or forward through the GC×GC modulator. In the second setup, in which the first secondary dimension column is installed in a separate GC-oven (oven-2), the overall selectivity of the second dimension can be tuned by adjusting the oven-2 temperature offset with respect to the main oven. The contribution of the first secondary dimension column to the overall secondary dimension separation can be decreased by applying a higher temperature offset. A real-life sample, the headspace of a coffee powder, was used to demonstrate the added value of tunable GC×GC by solving coelutions of some specific aroma compounds. Besides optimizing the overall GC×GC separation, by altering the second dimension column selectivity, these set-ups also offer enhanced possibilities for qualitative analysis. By stepwise altering the selectivity of the second dimension, classes of compounds showing similar retention behavior could be discriminated.