Critical aspects of the Bayesian approach to phase I cancer trials

141

103

Purpose: The cyclin-dependent kinase (CDK) 4/6 inhibitor, ribociclib (LEE011), displayed preclinical activity in neuroblastoma and malignant rhabdoid tumor (MRT) models. In this phase I study, the maximum tolerated dose (MTD) and recommended phase II dose (RP2D), safety, pharmacokinetics (PK), and preliminary activity of single-agent ribociclib were investigated in pediatric patients with neuroblastoma, MRT, or other cyclin D-CDK4/6-INK4-retinoblastoma pathwayaltered tumors.Experimental Design: Patients (aged 1-21 years) received escalating once-daily oral doses of ribociclib (3-weeks-on/1-week-off). Dose escalation was guided by a Bayesian logistic regression model with overdose control and real-time PK.Results: Thirty-two patients (median age, 5.5 years) received ribociclib 280, 350, or 470 mg/m 2 . Three patients had doselimiting toxicities of grade 3 fatigue (280 mg/m 2 ; n ¼ 1) or grade 4 thrombocytopenia (470 mg/m 2 ; n ¼ 2). Most common treatment-related adverse events (AE) were hematologic: neutropenia (72% all-grade/63% grade 3/4), leukopenia (63%/ 38%), anemia (44%/3%), thrombocytopenia (44%/28%), and lymphopenia (38%/19%), followed by vomiting (38%/0%), fatigue (25%/3%), nausea (25%/0%), and QTc prolongation (22%/0%). Ribociclib exposure was dose-dependent at 350 and 470 mg/m 2 [equivalent to 600 (RP2D)-900 mg in adults], with high interpatient variability. Best overall response was stable disease (SD) in nine patients (seven with neuroblastoma, two with primary CNS MRT); five patients achieved SD for more than 6, 6, 8, 12, and 13 cycles, respectively.Conclusions: Ribociclib demonstrated acceptable safety and PK in pediatric patients. MTD (470 mg/m 2 ) and RP2D (350 mg/m 2 ) were equivalent to those in adults. Observations of prolonged SD support further investigation of ribociclib combined with other agents in neuroblastoma and MRT.

Section: Statistical Analysesmentioning

confidence: 99%

A Phase I Study of the CDK4/6 Inhibitor Ribociclib (LEE011) in Pediatric Patients with Malignant Rhabdoid Tumors, Neuroblastoma, and Other Solid Tumors

Geoerger

Bourdeaut

DuBois

et al. 2017

141

103

“…NCT02043288). The Bayesian CRM model originated from Neuenschwander and was simulated, designed, and implemented using Fixed and Adaptive Clinical Trial Simulator (FACTS) software version 5.6 (22). The goals of the phase Ib portion of the trial were to determine the MTD and RP2D of NC-6004 in combination with gemcitabine and evaluate the initial activity and tolerability profile of the combination.…”

Section: Translational Relevancementioning

confidence: 99%

Phase Ib/II Trial of NC-6004 (Nanoparticle Cisplatin) Plus Gemcitabine in Patients with Advanced Solid Tumors

Subbiah

Grilley‐Olson

Combest

et al. 2018

Purpose: NC-6004, a novel cisplatin nanoparticle developed using micellar technology exhibits sustained release of cisplatin and selective distribution to tumors. Preclinical data demonstrated a favorable tolerability profile and preserved or improved antitumor activity compared with cisplatin across animal models. We evaluated the safety and tolerability of NC-6004 and gemcitabine using a Bayesian continual reassessment model (N-CRM) to determine the optimal dose.Experimental Design: Patients with advanced solid tumors received NC-6004 at 60 to 180 mg/m 2 on day 1 and gemcitabine at 1,250 mg/m 2 on days 1 and 8 every 3 weeks. Dose escalation of NC-6004 began with a single patient run-in until a dose-limiting toxicity occurred at 180 mg/m 2 . Cohorts of four patients were enrolled at doses predicted by the N-CRM. The maximum tolerated dose (MTD) was defined as having the greatest probability of target toxicity <25%. Quality of life was assessed using EORTC-QLQ-C30.Results: Among 22 patients, the most common grade III/IV hematologic adverse events were leukopenia (68%) and thrombocytopenia (59%). Of 20 pretreated patients evaluable for response, half were previously exposed to a platinum agent. The MTD was 135 mg/m 2 . Nine patients were treated at the MTD with median treatment duration of 15 weeks (range, 3-50). Tumor shrinkage occurred in 11 (55%), partial responses in 3 (15%), and stable disease in 14 (70%). Most patients reported stable or improved EORTC QLQ-C30 scores.Conclusions: Greater cisplatin equivalent doses were achieved with no clinically significant neuro-, oto-, or nephrotoxicity. These data demonstrate tolerability and promising activity of NC-6004 in combination with gemcitabine.

“…These data support ongoing clinical investigations of sonidegib as a single agent in BCC and hedgehog pathway-activated medulloblastoma, and as a combination partner with other agents in other malignant disease settings. escalation decisions (15,16). A DLT was defined as a significant adverse event or abnormal laboratory parameter adjudged to be Common Terminology Criteria for Adverse Events (CTCAE version 3.0) grade !3 in severity and considered unrelated to disease progression, intercurrent illness, or concomitant medications.…”

Section: Translational Relevancementioning

confidence: 99%

A Phase I, Multicenter, Open-Label, First-in-Human, Dose-Escalation Study of the Oral Smoothened Inhibitor Sonidegib (LDE225) in Patients with Advanced Solid Tumors

Rodón

Tawbi

Thomas

et al. 2014

201

214

Purpose: This phase I trial was undertaken to determine the maximum tolerated dose (MTD), doselimiting toxicities (DLT), safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of the novel smoothened inhibitor sonidegib (LDE225), a potent inhibitor of hedgehog signaling, in patients with advanced solid tumors.Experimental Design: Oral sonidegib was administered to 103 patients with advanced solid tumors, including medulloblastoma and basal cell carcinoma (BCC), at doses ranging from 100 to 3,000 mg daily and 250 to 750 mg twice daily, continuously, with a single-dose pharmacokinetics run-in period. Dose escalations were guided by a Bayesian logistic regression model. Safety, tolerability, efficacy, pharmacokinetics, and biomarkers in skin and tumor biopsies were assessed.Results: The MTDs of sonidegib were 800 mg daily and 250 mg twice daily. The main DLT of reversible grade 3/4 elevated serum creatine kinase (18% of patients) was observed at doses ! the MTD in an exposuredependent manner. Common grade 1/2 adverse events included muscle spasm, myalgia, gastrointestinal toxicities, increased liver enzymes, fatigue, dysgeusia, and alopecia. Sonidegib exposure increased dose proportionally up to 400 mg daily, and displayed nonlinear pharmacokinetics at higher doses. Sonidegib exhibited exposure-dependent reduction in GLI1 mRNA expression. Tumor responses observed in patients with medulloblastoma and BCC were associated with evidence of hedgehog pathway activation.Conclusions: Sonidegib has an acceptable safety profile in patients with advanced solid tumors and exhibits antitumor activity in advanced BCC and relapsed medulloblastoma, both of which are strongly associated with activated hedgehog pathway, as determined by gene expression.