Application of Pharmacokinetic/Pharmacodynamic Modeling to Bridge Mouse Antitumor Efficacy and Monkey Toxicology Data for Determining the Therapeutic Index of an Interleukin-10 Fc Fusion Protein.

Pharmacokinetic/pharmacodynamic (PK/PD) modeling was performed to quantitatively integrate preclinical pharmacology and toxicology data for determining the therapeutic index (TI) of an interleukin-10 (IL-10) fragment crystallizable (Fc) fusion protein. Mouse Fc fused with mouse IL-10 (mFc-mIL-10) was studied in mice for antitumor efficacy, and the elevation of interleukin-18 (IL-18) was examined as a PD biomarker. The in vivo mFc-mIL-10 EC50 for the IL-18 induction was estimated to be 2.4 nM, similar to the in vitro receptor binding affinity (Kd) of 3.2 nM. The IL-18 induction was further evaluated in cynomolgus monkeys, where the in vivo induction EC50 by a human IL-10 human Fc-fusion protein (hFc-hIL-10) was 0.08 nM vs. 0.3 nM measured as the in vitro Kd. The extent of the IL-18 induction correlated with mouse antitumor efficacy and was used to connect mouse efficacy to that in monkeys. The PD-based efficacious dose projected in monkeys was comparable to the results obtained using a PK-based method in which mouse efficacious exposure was targeted and corrected for affinity differences between the species. Furthermore, PK/PD relationships were developed for anemia and thrombocytopenia in monkeys treated with hFc-hIL-10, with thrombocytopenia predicted to be dose-limiting toxicity. Using quantitative pharmacology and toxicology information obtained through modeling work in the same species, the TI of hFc-hIL-10 in monkeys was determined to be 2.4 (vs. PD-based efficacy) and 1.2-3 (vs. PK-based efficacy), indicating a narrow safety margin. The model-based approaches were proven valuable to the developability assessment of the IL-10 Fc-fusion protein.

Continuing to Broaden Eligibility Criteria to Make Clinical Trials More Representative and Inclusive: ASCO-Friends of Cancer Research Joint Research Statement.

PURPOSE: Restrictive clinical trial eligibility criteria (EC) limit the number of patients who can enroll and potentially benefit from protocol-driven, investigational treatment plans and reduce the generalizability of trial results to the broader population. Following publication of expert stakeholder recommendations for broadening EC in 2017, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (Friends) convened working groups to produce additional recommendations and analyze the potential impact on clinical trials using real-world data. EXPERIMENTAL DESIGN: Multistakeholder working groups were appointed by an ASCO-Friends leadership group to propose recommendations for more inclusive EC related to: washout periods, concomitant medications, prior therapies, laboratory reference ranges and test intervals, and performance status. RESULTS: The four working groups, ASCO Board of Directors, and Friends leadership support the recommendations included in this statement to modernize EC related to washout periods, concomitant medications, prior therapies, laboratory references ranges and test intervals, and performance status to make trial populations more inclusive and representative of cancer patient populations. CONCLUSIONS: Implementation of the recommendations is intended to result in greater ease of determining patient eligibility. Increased opportunities for patient participation in research will help address longstanding underrepresentation of certain groups in clinical trials and produce evidence that is more informative for a broader patient population. More patients eligible will also likely speed clinical trial accrual.See related commentary by Giantonio, p. 2369.

The effect of sonidegib (LDE225) on the pharmacokinetics of bupropion and warfarin in patients with advanced solid tumours.

AIMS: We evaluated the potential effect of sonidegib at an oral dose of 800 mg once daily (QD) on the pharmacokinetics (PK) of the probe drugs warfarin (CYP2C9) and bupropion (CYP2B6). METHODS: This was a multicentre, open-label study to evaluate the effect of sonidegib on the PK of the probe drugs warfarin and bupropion in patients with advanced solid tumours. Cohort 1 patients received a single warfarin 15-mg dose on Day 1 of the run-in period and on Cycle 2 Day 22 (C2D22) of sonidegib administration. Cohort 2 patients received a single bupropion 75-mg dose on Day 1 of run-in period and on C2D22 of sonidegib administration. Sonidegib 800 mg QD oral dosing began on Cycle 1 Day 1 of a 28-day cycle after the run-in period in both cohorts. RESULTS: The geometric means ratios [90% confidence interval] for (S)-warfarin with and without sonidegib were: area under the concentration-time curve from time 0 to infinity (AUCinf ) 1.15 [1.07, 1.24] and maximum plasma concentration (Cmax ) 0.88 [0.81, 0.97]; and for (R)-warfarin were: AUCinf 1.10 [0.98, 1.24] and Cmax 0.93 [0.87, 1.0]. The geometric means ratios [90% confidence interval] of bupropion with and without sonidegib were: AUCinf 1.10 [0.99, 1.23] and Cmax 1.16 [0.95, 1.42]. Sonidegib 800 mg had a safety profile that was similar to that of lower dose sonidegib 200 mg and was unaffected by single doses of the probe drugs. CONCLUSIONS: Sonidegib dosed orally at 800 mg QD (higher than the Food and Drug Administration-approved dose) did not impact the PK or pharmacodynamics of warfarin (CYP2C9 probe substrate) or the PK of bupropion (CYP2B6 probe substrate).

Correction to: A window-of-opportunity trial of the CXCR1/2 inhibitor reparixin in operable HER-2-negative breast cancer.

An amendment to this paper has been published and can be accessed via the original article.

A window-of-opportunity trial of the CXCR1/2 inhibitor reparixin in operable HER-2-negative breast cancer.

BACKGROUND: Cancer stem cells (CSCs) are purported to be responsible for tumor initiation, treatment resistance, disease recurrence, and metastasis. CXCR1, one of the receptors for CXCL8, was identified on breast cancer (BC) CSCs. Reparixin, an investigational allosteric inhibitor of CXCR1, reduced the CSC content of human BC xenograft in mice. METHODS: In this multicenter, single-arm trial, women with HER-2-negative operable BC received reparixin oral tablets 1000 mg three times daily for 21 days before surgery. Primary objectives evaluated the safety of reparixin and the effects of reparixin on CSC and tumor microenvironment in core biopsies taken at baseline and at treatment completion. Signal of activity was defined as a reduction of ≥ 20% in ALDH+ or CD24-/CD44+ CSC by flow cytometry, with consistent reduction by immunohistochemistry. RESULTS: Twenty patients were enrolled and completed the study. There were no serious adverse reactions. CSC markers ALDH+ and CD24-/CD44+ measured by flow cytometry decreased by ≥ 20% in 4/17 and 9/17 evaluable patients, respectively. However, these results could not be confirmed by immunofluorescence due to the very low number of CSC. CONCLUSIONS: Reparixin appeared safe and well-tolerated. CSCs were reduced in several patients as measured by flow cytometry, suggesting targeting of CXCR1 on CSC. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT01861054. Registered on April 18, 2013.

A Phase Ib/II Trial of the First-in-Class Anti-CXCR4 Antibody Ulocuplumab in Combination with Lenalidomide or Bortezomib Plus Dexamethasone in Relapsed Multiple Myeloma.

PURPOSE: Ulocuplumab (BMS-936564) is a first-in-class fully human IgG4 monoclonal anti-CXCR4 antibody that inhibits the binding of CXCR4 to CXCL12. PATIENTS AND METHODS: This phase Ib/II study aimed to determine the safety and tolerability of ulocuplumab alone and in combination with lenalidomide and dexamethasone (Arm A), or bortezomib and dexamethasone (Arm B), in patients with relapsed/refractory multiple myeloma. RESULTS: Forty-six patients were evaluated (median age, 60 years; range, 53-67). The median number of prior therapies was 3 (range, 1-11), with 70% of subjects having received ≥3. This trial had a dose-escalation and a dose-expansion part. Using a 3+3 design on both arms of the trial, ulocuplumab's dose was escalated to a maximum of 10 mg/kg without reaching MTD. The most common treatment-related adverse events (AE) were neutropenia (13 patients, 43.3%) in Arm A and thrombocytopenia (6 patients, 37.5%) in Arm B. No deaths related to study drugs occurred. The combination of ulocuplumab with lenalidomide and dexamethasone showed a high response rate (PR or better) of 55.2% and a clinical benefit rate of 72.4%, even in patients who had been previously treated with immunomodulatory agents (IMiD). CONCLUSIONS: This study showed that blockade of the CXCR4-CXCL12 axis by ulocuplumab is safe with acceptable AEs and leads to a high response rate in combination with lenalidomide and dexamethasone in patients with relapsed/refractory myeloma, making CXCR4 inhibitors a promising class of antimyeloma drugs that should be further explored in clinical trials.

Evaluation of pharmacokinetics and safety of cetuximab with cisplatin/carboplatin in patients with advanced solid tumor: Result from phase II studies.

The pharmacokinetics and potential drug-drug interactions between cetuximab and cisplatin or carboplatin from two studies (JXBA and JXBB) were evaluated. These studies were multicenter, open-label phase II trials designed to evaluate the drug-drug interactions between cetuximab (400 mg m-2 initial dose) and cisplatin (JXBA; 100 mg m-2) or carboplatin (JXBB; area under the curve [AUC] = 5 mg × min mL-1) with or without 5-fluorouracil (5FU) in patients with advanced solid tumors. Concentrations of cetuximab, cisplatin and carboplatin were determined using analytical methods. The safety and tolerability of cetuximab in combination with cisplatin or carboplatin was also determined in all treated patients. The JXBA study showed that cetuximab serum concentrations were similar when cetuximab was administered alone or in combination with cisplatin. The Cmax, tmax and overall AUC for the cetuximab group (194 µg mL-1, 2.0 hour, 14 900 µg × h mL-1) and the cetuximab and cisplatin combination group (192 µg mL-1, 1.99 hour, 16 300 µg × h mL-1) were similar. The JXBB study showed that mean cetuximab serum concentrations were similar when cetuximab was administered alone or in combination with carboplatin. The Cmax, tmax and overall AUC for the cetuximab group (199 µg mL-1, 1.15 hour, 17 200 µg × h mL-1) and the cetuximab and carboplatin combination group (199 µg mL-1, 3.17 h, 16 800 µg × h mL-1) were similar. Both studies showed that the safety profile was consistent with known side effects of cetuximab, platinum-based therapies and 5-FU. There was no clinically relevant change in cetuximab pharmacokinetics when it was administered in combination with cisplatin or carboplatin.

Assessing an ASCO Decision Aid for Improving the Accuracy and Attribution of Serious Adverse Event Reporting From Investigators to Sponsors.

PURPOSE: Investigators often send reports to sponsors that incorrectly categorize adverse event (AE)s as serious or attribute AEs to investigational drugs. Such errors can contribute to high volumes of uninformative investigational new drug safety reports that sponsors submit to the US Food and Drug Administration and participating investigators, which strain resources and impede the detection of valid safety signals. To improve the quality of serious AE (SAE) reporting by physician-investigators and research staff, ASCO developed and tested a Decision Aid. METHODS: A preliminary study with crossover design was conducted in a convenience sample. Physician-investigators and research staff were randomly assigned to receive case studies. Case studies were assessed for seriousness and attribution, first unassisted and then with the Decision Aid. Participants completed a feedback survey about the Decision Aid. Effectiveness of reporting and attribution are reported as odds ratios (ORs) with 95% CI. Power to detect associations was limited because of a small sample size. RESULTS: The Decision Aid did not significantly affect accuracy of determining seriousness (OR, 0.87; 95% CI, 0.31 to 2.46), but it did significantly increase accuracy of attributing an SAE to a drug (OR, 3.60; 95% CI, 1.15 to 11.4). Most of the 29 participants reported that the Decision Aid was helpful (93%) and improved decision-making time (69%) and confidence in reporting (83%), and that they would use the Decision Aid in practice (83%). CONCLUSION: The Decision Aid shows promise as a method to improve the quality of SAE attribution, which may improve the detection of valid safety signals and reduce the administrative burden of uninformative investigational new drug safety reports. Study of the Decision Aid in a larger sample with analysis stratified by participant role and SAE reporting experience would further assess the tool's impact.

Drug screening to target nuclear orphan receptor NR4A2 for cancer therapeutics.

BACKGROUND: Our previous study suggested NR4A2, a subfamily member of orphan nuclear receptors, is essential for survival of human cancer cells such as mucoepidermoid carcinoma (MEC). METHODS: We conducted high throughput drug screening for NR4A2 inhibitors as a novel therapeutic modality. Positive screening was performed using a luciferase reporter vector containing NR4A2 binding sequence, and a CRE-reporter control vector was used to eliminate false positives. In vitro assays for positive hits were conducted. RESULTS: A total of 23 Food and Drug Administration (FDA) and 43 Life Science Library compounds were identified, including several epidermal growth factor inhibitors and Src inhibitors. Subsequent in vitro assays confirmed that identified compounds were preferentially active in NR4A2+ cancer cells. Several candidate compounds appeared to suppress NR4A2 via inhibition of p-ERK, whereas a novel compound KU0171309 may act as a more direct inhibitor. CONCLUSIONS: Further research should focus on homologue selectivity, in vivo activity, and definitively deciphering the mechanism of action of KU0171309.

Characterization of folate receptor alpha (FRα) expression in archival tumor and biopsy samples from relapsed epithelial ovarian cancer patients: A phase I expansion study of the FRα-targeting antibody-drug conjugate mirvetuximab soravtansine.

PURPOSE: To characterize folate receptor alpha (FRα) expression in archival and fresh biopsy tumor samples from relapsed ovarian cancer patients. METHODS: Patients with ovarian tumors amenable to biopsy were eligible to enroll. Eligibility included a minimum requirement of FRα positivity in archival tumor samples (≥25% of cells with ≥2+ staining intensity). Patients received mirvetuximab soravtansine at 6mg/kg once every 3weeks. Core needle biopsies were collected before and after treatment and FRα levels assessed by immunohistochemistry. Descriptive statistics were used to summarize the association between receptor expression and response. RESULTS: Twenty-seven heavily pre-treated patients were enrolled. Six individuals (22%) did not have evaluable pre-treatment biopsies due to insufficient tumor cells. The concordance of FRα expression in archival and biopsy tissues was 71%, and no major shifts in receptor expression were seen in matched pre- and post-treatment biopsy samples. Adverse events were generally mild (≤grade 2) with keratopathy (48%), fatigue (44%), diarrhea, and blurred vision (each 37%) being the most common treatment-related toxicities. The confirmed objective response rate (ORR) was 22%, including two complete responses and four partial responses. Superior efficacy measures were observed in the subset of patients with the highest FRα levels (ORR, 31%; progression-free survival, 5.4months). CONCLUSION: Concordance of FRα expression in biopsy versus archival tumor samples suggests that archival tissue can reliably identify patients with receptor-positive tumors and is appropriate for patient selection in mirvetuximab soravtansine clinical trials. Regardless of the tissue source analyzed, higher FRα expression was associated with greater antitumor activity.

Phase Ib Pilot Study to Evaluate Reparixin in Combination with Weekly Paclitaxel in Patients with HER-2-Negative Metastatic Breast Cancer.

Purpose: Chemokine receptor 1 (CXCR1) is recognized as an actionable receptor selectively expressed by breast cancer stem cells (BCSCs). Reparixin is an investigational allosteric inhibitor of chemokine receptors 1 and 2 (CXCR1/2), and demonstrates activity against BCSCs in human breast cancer xenografts. This phase Ib clinical trial examined dose, safety, and pharmacokinetics of paclitaxel plus reparixin therapy, and explored effects of reparixin on BCSCs in patients with metastatic breast cancer (MBC) (trial registration ID: NCT02001974).Experimental Design: Eligible patients had MBC and were candidates for paclitaxel therapy. Study treatment included a 3-day run-in with reparixin oral tablets three times a day, followed by paclitaxel 80 mg/m2/week (days 1, 8, and 15 for 28-day cycle) + reparixin tablets three times a day for 21/28 days; three dose cohorts were examined in a 3+3 dose escalation schema. Additional patients were recruited into an expansion cohort at the recommended phase II dose to further explore pharmacokinetics, safety, and biological effects of the combination therapy.Results: There were neither G4-5 adverse events nor serious adverse events related to study therapy and no interactions between reparixin and paclitaxel to influence their respective pharmacokinetic profiles. A 30% response rate was recorded, with durable responses >12 months in two patients. Exploratory biomarker analysis was inconclusive for therapy effect on BCSCs.Conclusions: Weekly paclitaxel plus reparixin in MBC appeared to be safe and tolerable, with demonstrated responses in the enrolled population. Dose level 3, 1200 mg orally three times a day, was selected for further study in a randomized phase II trial (NCT02370238). Clin Cancer Res; 23(18); 5358-65. ©2017 AACR.

Phase 1 dose-escalation study of mirvetuximab soravtansine (IMGN853), a folate receptor α-targeting antibody-drug conjugate, in patients with solid tumors.

BACKGROUND: Mirvetuximab soravtansine (IMGN853) is an antibody-drug conjugate that selectively targets folate receptor α (FRα). In this phase 1 dose-escalation study, the authors investigated IMGN853 in patients with FRα-positive solid tumors. METHODS: Patients received IMGN853 on day 1 of a 21-day cycle (once every 3 weeks dosing), with cycles repeated until patients experienced dose-limiting toxicity or progression. Dose escalation commenced in single-patient cohorts for the first 4 planned dose levels and then followed a standard 3 + 3 scheme. The primary objectives were to determine the maximum tolerated dose and the recommended phase 2 dose. Secondary objectives were to determine safety and tolerability, to characterize the pharmacokinetic profile, and to describe preliminary clinical activity. RESULTS: In total, 44 patients received treatment at doses escalating from 0.15 to 7.0 mg/kg. No meaningful drug accumulation was observed with the dosing regimen of once every 3 weeks. The most common treatment-related adverse events were fatigue, blurred vision, and diarrhea, the majority of which were grade 1 or 2. The dose-limiting toxicities observed were grade 3 hypophosphatemia (5.0 mg/kg) and grade 3 punctate keratitis (7.0 mg/kg). Two patients, both of whom were individuals with epithelial ovarian cancer, achieved confirmed tumor responses according to Response Evaluation Criteria in Solid Tumors 1.1, and each was a partial response. CONCLUSIONS: IMGN853 demonstrated a manageable safety profile and encouraging preliminary clinical activity, particularly in patients with ovarian cancer. The results establish a recommended phase 2 dosing of 6.0 mg/kg (based on adjusted ideal body weight) once every 3 weeks. Cancer 2017. © 2017 American Cancer Society. Cancer 2017;123:3080-7. © 2017 American Cancer Society.

Sponsors' and investigative staffs' perceptions of the current investigational new drug safety reporting process in oncology trials.

BACKGROUND/AIMS: The Food and Drug Administration's final rule on investigational new drug application safety reporting, effective from 28 March 2011, clarified the reporting requirements for serious and unexpected suspected adverse reactions occurring in clinical trials. The Clinical Trials Transformation Initiative released recommendations in 2013 to assist implementation of the final rule; however, anecdotal reports and data from a Food and Drug Administration audit indicated that a majority of reports being submitted were still uninformative and did not result in actionable changes. Clinical Trials Transformation Initiative investigated remaining barriers and potential solutions to full implementation of the final rule by polling and interviewing investigators, clinical research staff, and sponsors. METHODS: In an opinion-gathering effort, two discrete online surveys designed to assess challenges and motivations related to management of expedited (7- to 15-day) investigational new drug safety reporting processes in oncology trials were developed and distributed to two populations: investigators/clinical research staff and sponsors. Data were collected for approximately 1 year. Twenty-hour-long interviews were also conducted with Clinical Trials Transformation Initiative-nominated interview participants who were considered as having extensive knowledge of and experience with the topic. Interviewees included 13 principal investigators/study managers/research team members and 7 directors/vice presidents of pharmacovigilance operations from 5 large global pharmaceutical companies. RESULTS: The investigative site's responses indicate that too many individual reports are still being submitted, which are time-consuming to process and provide little value for patient safety assessments or for informing actionable changes. Fewer but higher quality reports would be more useful, and the investigator and staff would benefit from sponsors'"filtering" of reports and increased sponsor communication. Sponsors replied that their greatest challenges include (1) lack of global harmonization in reporting rules, (2) determining causality, and (3) fear of regulatory repercussions. Interaction with the Food and Drug Administration has helped improve sponsors' adherence to the final rule, and sponsors would benefit from increased communication with the Food and Drug Administration and educational materials. CONCLUSION: The goal of the final rule is to minimize uninformative safety reports so that important safety signals can be captured and communicated early enough in a clinical program to make changes that help ensure patient safety. Investigative staff and sponsors acknowledge that the rule has not been fully implemented although they agree with the intention. Clinical Trials Transformation Initiative will use the results from the surveys and interviews to develop new recommendations and educational materials that will be available to sponsors to increase compliance with the final rule and facilitate discussion between sponsors, investigators, and Food and Drug Administration representatives.

Safety and Activity of Mirvetuximab Soravtansine (IMGN853), a Folate Receptor Alpha-Targeting Antibody-Drug Conjugate, in Platinum-Resistant Ovarian, Fallopian Tube, or Primary Peritoneal Cancer: A Phase I Expansion Study.

Purpose This phase I expansion cohort study evaluated the safety and clinical activity of mirvetuximab soravtansine (IMGN853), an antibody-drug conjugate consisting of a humanized anti-folate receptor alpha (FRα) monoclonal antibody linked to the tubulin-disrupting maytansinoid DM4, in a population of patients with FRα-positive and platinum-resistant ovarian cancer. Patients and Methods Patients with platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer received IMGN853 at 6.0 mg/kg (adjusted ideal body weight) once every 3 weeks. Eligibility included a minimum requirement of FRα positivity by immunohistochemistry (≥ 25% of tumor cells with at least 2+ staining intensity). Adverse events, tumor response (via Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1), and progression-free survival (PFS) were determined. Results Forty-six patients were enrolled. Adverse events were generally mild (≤ grade 2), with diarrhea (44%), blurred vision (41%), nausea (37%), and fatigue (30%) being the most commonly observed treatment-related toxicities. Grade 3 fatigue and hypotension were reported in two patients each (4%). For all evaluable patients, the confirmed objective response rate was 26%, including one complete and 11 partial responses, and the median PFS was 4.8 months. The median duration of response was 19.1 weeks. Notably, in the subset of patients who had received three or fewer prior lines of therapy (n = 23), an objective response rate of 39%, PFS of 6.7 months, and duration of response of 19.6 weeks were observed. Conclusion IMGN853 exhibited a manageable safety profile and was active in platinum-resistant ovarian cancer, with the strongest signals of efficacy observed in less heavily pretreated individuals. On the basis of these findings, the dose, schedule, and target population were identified for a phase III trial of IMGN853 monotherapy in patients with platinum-resistant disease.

Primary lung mucoepidermoid carcinoma: analysis of prognostic factors using surveillance, epidemiology and end results program.

INTRODUCTION: Mucoepidermoid carcinoma (MEC) primarily occurs in salivary glands, but can also arise in other organs; however, the impact of primary location on patient prognosis is largely unknown. METHODS: Using Surveillance, Epidemiology and End Results Program (SEER) data we investigated whether the clinical and prognostic features of MEC differed among multiple organ sites. The SEER-18 dataset from 18 cancer registries in the US between 1972 and 2012 was chosen. The common organ sites with 100 or more cases were further analyzed. Survival analysis included Log-rank tests of Kaplan-Meier curves and univariate/multivariate proportional hazard analysis. RESULTS: A total of 7,191 MEC cases with survival data were identified in the SEER data. Major salivary gland (MSG) was the primary site in 52.9% of cases, followed by gum and other mouth (23.6%), lung (5.9%), tongue (3.4%) and others. Compared to MSG-MEC, primary lung MEC had significantly more patients with age <=70, diagnosis in 2002 and earlier, distant stage, undetermined grade and nonsurgical treatment. Primary lung MEC, older age, male gender, early year of diagnosis, distant stage, high histologic grade and radiation alone were significantly associated with poor 5-year disease-specific survival rate. Among patients with primary lung MEC, univariate analysis demonstrated that those with main bronchus or upper lobe primary sites had significantly decreased 5-year disease-specific survival rate. CONCLUSIONS: This study suggests that there is a major difference in prognosis of MEC among primary sites. Primary lung MEC might have poor prognosis over MSG-MEC.

Pharmacokinetics of ixazomib, an oral proteasome inhibitor, in solid tumour patients with moderate or severe hepatic impairment.

AIM: The aim of the present study was to characterize the pharmacokinetics of the oral proteasome inhibitor, ixazomib, in patients with solid tumours and moderate or severe hepatic impairment, to provide posology recommendations. METHODS: Eligible adults with advanced malignancies for which no further effective therapy was available received a single dose of ixazomib on day 1 of the pharmacokinetic cycle; patients with normal hepatic function, moderate hepatic impairment or severe hepatic impairment received 4 mg, 2.3 mg or 1.5 mg, respectively. Blood samples for single-dose pharmacokinetic characterization were collected over 336 h postdose. After sampling, patients could continue to receive ixazomib on days 1, 8 and 15 in 28-day cycles. RESULTS: Of 48 enrolled patients (13, 15 and 20 in the normal, moderate and severe groups, respectively), 43 were pharmacokinetics-evaluable. Ixazomib was rapidly absorbed (median time to reach peak concentration was 0.95-1.5 h) and highly bound to plasma proteins, with a similar mean fraction bound (~99%) across the three groups. In patients with moderate/severe hepatic impairment (combined group), the geometric least squares mean ratios (90% confidence interval) for unbound and total dose-normalized area under the plasma concentration vs. time curve from time zero to the time of the last quantifiable concentration in reference to the normal hepatic function group were 1.27 (0.75, 2.16) and 1.20 (0.79, 1.82), respectively. Seven (15%) of the 48 patients experienced a grade 3 drug-related adverse event; there were no drug-related grade 4 adverse events. CONCLUSIONS: In patients with moderate/severe hepatic impairment, unbound and total systemic exposures of ixazomib were 27% and 20% higher, respectively, vs. normal hepatic function. A reduced ixazomib starting dose of 3 mg is recommended for patients with moderate or severe hepatic impairment.