Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03).

PURPOSE: The PALLAS study investigated whether the addition of palbociclib, an oral CDK4/6 inhibitor, to adjuvant endocrine therapy (ET) improves invasive disease-free survival (iDFS) in early hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In this analysis, we evaluated palbociclib exposure and discontinuation in PALLAS. METHODS: Patients with stage II-III HR+, HER2- disease were randomly assigned to 2 years of palbociclib with adjuvant ET versus ET alone. The primary objective was to compare iDFS between arms. Continuous monitoring of toxicity, dose modifications, and early discontinuation was performed. Association of baseline covariates with time to palbociclib reduction and discontinuation was analyzed with multivariable competing risk models. Landmark and inverse probability weighted per-protocol analyses were performed to assess the impact of drug persistence and exposure on iDFS. RESULTS: Of the 5,743 patient analysis population (2,840 initiating palbociclib), 1,199 (42.2%) stopped palbociclib before 2 years, the majority (772, 27.2%) for adverse effects, most commonly neutropenia and fatigue. Discontinuation of ET did not differ between arms. Discontinuations for non-protocol-defined reasons were greater in the first 3 months of palbociclib, and in the first calendar year of accrual, and declined over time. No significant relationship was seen between longer palbociclib duration or ≥ 70% exposure intensity and improved iDFS. In the weighted per-protocol analysis, no improvement in iDFS was observed in patients receiving palbociclib versus not (hazard ratio 0.89; 95% CI, 0.72 to 1.11). CONCLUSION: Despite observed rates of discontinuation in PALLAS, analyses suggest that the lack of significant iDFS difference between arms was not directly related to inadequate palbociclib exposure. However, the discontinuation rate illustrates the challenge of introducing novel adjuvant treatments, and the need for interventions to improve persistence with oral cancer therapies.

The scent of fear.

In this study we tried to find out if fear can be detected from human body odours. Female subjects wore under-arm axillary pads while watching a terrifying film. Saliva cortisol samples were taken before and after the film presentation as a hormonal measure for the fear response. The fear experience itself was measured by Spielberger's State-Trait Anxiety Inventory. A "neutral" film, shown one day after the "fear" film, was used as a control in a repeated measures design. In part two of the experiment, the axillary pads were presented to female subjects in a triple forced choice test. Results show that subjects were able to discriminate between fear and non-fear axillary pads, suggesting that women are indeed able to detect "the scent of fear". A direct correlation between induced fear, changes in cortisol levels and smell ratings could not be established. Thus cortisol levels are probably not the inducer of the scent of fear and a hypothetical fear pheromone could have other origins.