Dose Rationalization of Pembrolizumab and Nivolumab Using Pharmacokinetic Modeling and Simulation and Cost Analysis

Pembrolizumab and nivolumab are highly selective anti-programmed cell death 1 (PD-1) antibodies approved for the treatment of advanced malignancies. Variable exposure and significant wastage have been associated with body size dosing of monoclonal antibodies (mAbs). The following dosing strategies were evaluated using simulations: body weight, dose banding, fixed dose, and pharmacokinetic (PK)-based methods. The relative cost to body weight dosing for band, fixed 150 mg and 200 mg, and PK-derived strategies were -15%, -25%, + 7%, and -16% for pembrolizumab and -8%, -6%, and -10% for band, fixed, and PK-derived strategies for nivolumab, respectively. Relative to mg/kg doses, the median exposures were -1.0%, -4.6%, + 27.1%, and +3.0% for band, fixed 150 mg, fixed 200 mg, and PK-derived strategies, respectively, for pembrolizumab and -3.1%, + 1.9%, and +1.4% for band, fixed 240 mg, and PK-derived strategies, respectively, for nivolumab. Significant wastage can be reduced by alternative dosing strategies without compromising exposure and efficacy.

Using Organizational Philosophy to Create a Self-Sustaining Compensation Plan Without Harming Academic Missions

PROBLEM

Academic physician reimbursement has moved to productivity-based compensation plans. To be sustainable, such plans must be self-funding. Additionally, unless research and education are appropriately valued, faculty involved in these efforts will become disillusioned, yet revenue generation in these activities is less robust than for clinical care activities.

APPROACH

Faculty at the Department of Medicine, University of Florida Health, elected a committee of junior and senior faculty and division chiefs to restructure the compensation plan in fiscal year (FY) 2011. This committee was charged with designing a new compensation plan based on seven principles of organizational philosophy: equity, compensation coupled to productivity, authority aligned with responsibility, respect for all academic missions, transparency, professionalism, and self-funding in each academic mission.

OUTCOMES

The new compensation plan was implemented in FY2013. A survey administered at the end of FY2015 showed that 61% (76/125) of faculty were more satisfied with this plan than the previous plan. Since the year before implementation, clinical relative value units per faculty increased 7% (from 3,458 in FY2012 to 3,704 in FY2015, P < .002), incentives paid per faculty increased 250% (from $3,191 in FY2012 to $11,153 in FY2015, P ≤ .001), and publications per faculty increased 15% (from 2.6 in FY2012 to 3.0 in FY2015, P < .001). Grant submissions, external funding, and teaching hours also increased per faculty but did not reach statistical significance.

NEXT STEPS

An important next step will be to incorporate quality metrics into the compensation plan, without affecting costs or throughput.

Direct determination of the positions of the deuterium atoms of the bound water in -concanavalin A by neutron Laue crystallography

The correct positions of the deuterium (D) atoms of many of the bound waters in the protein concanavalin A are revealed by neutron Laue diffraction. The approach includes cases where these water D atoms show enough mobility to render them invisible even to ultra-high resolution synchrotron-radiation X-ray crystallography. The positions of the bound water H atoms calculated on the basis of chemical and energetic considerations are often incorrect. The D-atom positions for the water molecules in the Mn-, Ca- and sugar-binding sites of concanavalin A are described in detail.

Personal history of childhood abuse among clinicians

We conducted a survey to determine the prevalence, characteristics, and effects of a history of childhood sexual and physical abuse among professionals responsible for evaluating child sexual abuse allegations. A gender-stratified random sample of 1,635 United States clinicians was drawn from the most current national directories of clinical social work, pediatrics, psychiatry, and psychology. We received 656 completed questionnaires, yielding a 42% response rate. Thirteen percent of the men and 20% of the women reported a personal history of childhood sexual abuse; 7.3% of the men and 6.9% of the women reported a history of physical abuse as children. The modal age at which both genders were sexually abused was 8 years. The modal age at the time of physical abuse was 10 years for both sexes. Of those sexually abused, 50% of both genders were sexually abused for only 1 year. Of those physically abused, more than 50% of both genders were physically abused for 3 or more years. Older females were more likely to report a history of sexual abuse than were their younger cohorts. In this population, physical abuse was overwhelmingly perpetrated by parents. However, the modal perpetrators of sexual abuse (for both females and males) were male acquaintances or male strangers. Fathers and stepfathers were unlikely to be perpetrators of sexual abuse (3% for males and 12% for females) in this sample. For both genders, particularly males, sexually abused respondents were less likely to be married than their nonabused cohorts. Both men and women who had been sexually abused were more likely to be in nonmarital relationships than were those who had not been sexually abused. Women who had been sexually abused were less likely to have raised children than were women who had not been sexually abused. Respondents who had been sexually abused and/or physically abused were more likely to believe allegations of sexual abuse contained in 16 vignettes alleging sexual abuse.

Clinician responses to sexual abuse allegations

We conducted a survey using an experimental design to identify how and to what extent specific personal and case factors affect clinicians' judgments about sexual abuse allegations. We drew a stratified random sample of 1,635 United States clinicians from national directories of clinical social work, pediatrics, psychiatry and psychology. Six hundred and fifty-six completed questionnaires were obtained, yielding a 42% response rate. We asked each subject to read and rate, on a 6 point scale, 16 vignettes alleging sexual abuse. The scale ranged from 1 (very confident it did not occur), to 6 (very confident it did occur). On average, respondents were "slightly confident sexual abuse had occurred" (M = 4.03; SD = 0.6). This finding was significantly different from a mean of 3.50, which is the expected null result. Seven case factors affected credibility ratings at the .01 level; perpetrators' race (Caucasians viewed as perpetrators more than minorities); perpetrators' relationship to victim (family members more often seen as perpetrators); victims' race (minorities more credible as victims); victims' affect (those showing negative affect more believable); age (younger victims more often seen as victimized); behavioral changes in the victim; and perpetrator's history of substance abuse. Six clinician factors were significant at the .05 level: age (younger clinicians were more credulous), gender (females more credulous), discipline (clinical social workers more credulous), theoretical orientation (family systems oriented more credulous) and personal history of sexual or physical abuse (abuse history more credulous).