Checkpoint inhibitors (CIs) are highly effective but can induce severe immune-related adverse events (irAEs), which cannot be predicted. We investigated whether human leukocyte antigen (HLA) genes predispose to developing of irAEs during therapy and thus hold a predictive role. We established a prospective observational single-centre study and collected data from patients with either metastatic non-small cell lung cancer (NSCLC) or metastatic melanoma, who were treated with anti-PD-1 (programmed cell death receptor 1), anti-CTLA4 (cytotoxic T-lymphocyte-associated protein 4) or both CIs combined. Data include irAEs and ranges from 15th July 2016 until 10th May 2018. In addition, we performed HLA typing via next generation sequencing. We enrolled 102 patients (median [range] age, 68 [62-74] years) with metastatic cancer in our study who received CI therapy. Of these patients, 59 (58%) developed one or more irAEs, among which pruritus (n = 32 (54%)) and rash (n = 24 (41%)) had the highest rates. We did not find evidence for a single HLA gene being associated with all irAEs (all P > .05). When assessing each irAE individually, we found a significant association between HLA-DRB1*11:01 and pruritus (OR = 4.53, X21,95 = 9.45, P < .01) as well as a nominally significant additive association between HLA-DQB1*03:01 and colitis (OR = 3.94, X21,95 = 5.67, P = .017). The presence of two HLA alleles that are known to predispose to autoimmune diseases were associated with the development of pruritus or colitis during therapy, suggesting a genetic aetiology of irAEs. Larger genome-wide association studies should be performed to confirm our findings.

Purpose: Paclitaxel and carboplatin are frequently used in advanced ovarian cancer following cytoreductive surgery. Threshold models have been used to predict paclitaxel pharmacokinetic-pharmacodynamics, whereas the time above paclitaxel plasma concentration of 0.05 to 0.2 μmol/L (t_{C > 0.05−0.2}) predicts neutropenia. The objective of this study was to build a population pharmacokinetic-pharmacodynamic model of paclitaxel/carboplatin in ovarian cancer patients. Experimental Design: One hundred thirty-nine ovarian cancer patients received paclitaxel (175 mg/m²) over 3 h followed by carboplatin area under the concentration-time curve 5 mg/mL*min over 30 min. Plasma concentration-time data were measured, and data were processed using nonlinear mixed-effect modeling. Semiphysiologic models with linear or sigmoidal maximum response and threshold models were adapted to the data. Results: One hundred five patients had complete pharmacokinetic and toxicity data. In 34 patients with measurable disease, objective response rate was 76%. Neutrophil and thrombocyte counts were adequately described by an inhibitory linear response model. Paclitaxel t_{C > 0.05} was significantly higher in patients with a complete (91.8 h) or partial (76.3 h) response compared with patients with progressive disease (31.5 h; P = 0.02 and 0.05, respectively). Patients with paclitaxel t_{C > 0.05} > 61.4 h (mean value) had a longer time to disease progression compared with patients with paclitaxel t_{C > 0.05} < 61.4 h (89.0 versus 61.9 weeks; P = 0.05). Paclitaxel t_{C > 0.05} was a good predictor for severe neutropenia (P = 0.01), whereas carboplatin exposure (C_max and area under the concentration-time curve) was the best predictor for thrombocytopenia (P < 10⁻⁴). Conclusions: In this group of patients, paclitaxel t_{C > 0.05} is a good predictive marker for severe neutropenia and clinical outcome, whereas carboplatin exposure is a good predictive marker for thrombocytopenia.

Variable chemotherapy exposure may cause toxicity or lack of efficacy. This study was initiated to validate pharmacokinetically (PK)-guided paclitaxel dosing in patients with advanced non-small-cell lung cancer (NSCLC) to avoid supra- or subtherapeutic exposure. Patients with newly diagnosed, advanced NSCLC were randomly assigned to receive up to 6 cycles of 3-weekly carboplatin AUC 6 or cisplatin 80 mg/m² either with standard paclitaxel at 200 mg/m² (arm A) or PK-guided dosing of paclitaxel (arm B). In arm B, initial paclitaxel dose was adjusted to body surface area, age, sex, and subsequent doses were guided by neutropenia and previous-cycle paclitaxel exposure [time above a plasma concentration of 0.05 µM (T_c>0.05)] determined from a single blood sample on day 2. The primary end point was grade 4 neutropenia; secondary end points included neuropathy, radiological response, progression-free survival (PFS) and overall survival (OS). Among 365 patients randomly assigned, grade 4 neutropenia was similar in both arms (19% versus 16%; P = 0.10). Neuropathy grade ≥2 (38% versus 23%, P < 0.001) and grade ≥3 (9% versus 2%, P < 0.001) was significantly lower in arm B, independent of the platinum drug used. The median final paclitaxel dose was significantly lower in arm B (199 versus 150 mg/m², P < 0.001). Response rate was similar in arms A and B (31% versus 27%, P = 0.405), as was adjusted median PFS [5.5 versus 4.9 months, hazard ratio (HR) 1.16, 95% confidence interval (CI) 0.91–1.49, P = 0.228] and OS (10.1 versus 9.5 months, HR 1.05, 95% CI 0.81–1.37, P = 0.682). PK-guided dosing of paclitaxel does not improve severe neutropenia, but reduces paclitaxel-associated neuropathy and thereby improves the benefit–risk profile in patients with advanced NSCLC. NCT01326767 (https://clinicaltrials.gov/ct2/show/NCT01326767).