Dose optimization for cancer treatments with considerations for late-onset toxicities.

Given that novel anticancer therapies have different toxicity profiles and mechanisms of action, it is important to reconsider the current approaches for dose selection. In an effort to move away from considering the maximum tolerated dose as the optimal dose, the Food and Drug Administration Project Optimus points to the need of incorporating long-term toxicity evaluation, given that many of these novel agents lead to late-onset or cumulative toxicities and there are no guidelines on how to handle them. Numerous methods have been proposed to handle late-onset toxicities in dose-finding clinical trials. A summary and comparison of these methods are provided. Moreover, using PI3K inhibitors as a case study, we show how late-onset toxicity can be integrated into the dose-optimization strategy using current available approaches. We illustrate a re-design of this trial to compare the approach to those that only consider early toxicity outcomes and disregard late-onset toxicities. We also provide proposals going forward for dose optimization in early development of novel anticancer agents with considerations for late-onset toxicities.

Incorporating patient-reported outcomes in dose-finding clinical trials with continuous patient enrollment.

Dose-finding clinical trials in oncology estimate the maximum tolerated dose (MTD), based on toxicity obtained from the clinician's perspective. While the collection of patient-reported outcomes (PROs) has been advocated to better inform treatment tolerability, there is a lack of guidance and methods on how to use PROs for dose assignments and recommendations. The PRO continual reassessment method (PRO-CRM) has been proposed to formally incorporate PROs into dose-finding trials. In this paper, we propose two extensions of the PRO-CRM, which allow continuous enrollment of patients and longer toxicity observation windows to capture late-onset or cumulative toxicities by using a weighted likelihood to include the partial toxicity follow-up information. The TITE-PRO-CRM uses both the PRO and the clinician's information during the trial for dose assignment decisions and at the end of the trial to estimate the MTD. The TITE-CRM + PRO uses clinician's information solely to inform dose assignments during the trial and incorporates PRO at the end of the trial for the estimation of the MTD. Simulation studies show that the TITE-PRO-CRM performs similarly to the PRO-CRM in terms of dose recommendation and assignments during the trial while almost halving trial duration in case of an accrual of two patients per observation window. The TITE-CRM + PRO slightly underperforms compared to the TITE-PRO-CRM, but similar performance can be attained by requiring larger sample sizes. We also show that the performance of the proposed methods is robust to higher accrual rates, different toxicity hazards, and correlated time-to-clinician toxicity and time-to-patient toxicity data.

Anti-Tumor Necrosis Factor α versus Tocilizumab in the Treatment of Refractory Uveitic Macular Edema: A Multicenter Study from the French Uveitis Network.

PURPOSE: To analyze the factors associated with response (control of ocular inflammation and corticosteroid-sparing effect) to biologics (anti-tumor necrosis factor [TNF]-α agents and tocilizumab) in patients with refractory uveitic macular edema (ME). DESIGN: Multicenter, retrospective, observational study. PARTICIPANTS: Adult patients with uveitic ME refractory to systemic corticosteroids, disease-modifying antirheumatic drugs, or both. METHODS: Patients received anti-TNF-α agents (infliximab 5 mg/kg at week 0, 2, 6, and every 4-6 weeks [n = 69] and adalimumab 40 mg/2 weeks [n = 80]) and tocilizumab (8 mg/kg every 4 weeks intravenously [n = 39] and 162 mg/week subcutaneously [n = 16]). MAIN OUTCOME MEASURES: Analysis of complete and partial response rates, relapse rate, low vision (visual acuity in at least 1 eye of ≥ 1 logarithm of the minimum angle of resolution), corticosteroid-sparing effect, and adverse events at 6 months. RESULTS: Two hundred four patients (median age, 40 years [interquartile range, 28-58 years]; 42.2% men) were included. Main causes of uveitis included Behçet's disease (17.2%), birdshot chorioretinopathy (11.3%), and sarcoidosis (7.4%). The overall response rate at 6 months was 46.2% (21.8% of complete response) with anti-TNF-α agents and 58.5% (35.8% of complete response) with tocilizumab. In multivariate analysis, treatment with tocilizumab (odds ratio, 2.10; 95% confidence interval [CI], 1.06-4.06; P = 0.03) was associated independently with complete response of uveitic ME compared with anti-TNF-α agents. Anti-TNF-α agents and tocilizumab did not differ significantly in terms of relapse rate (hazard ratio, 1.00; 95% CI, 0.31-3.18; P = 0.99) or occurrence of low vision (odds ratio, 1.02; 95% CI, 0.51-2.07; P = 0.95) or corticosteroid-sparing effect (P = 0.29). Adverse events were reported in 20.6% of patients, including serious adverse events reported in 10.8% of patients. CONCLUSIONS: Tocilizumab seems to improve complete response of uveitic ME compared with anti-TNF-α agents.

Mogamulizumab induces long-term immune restoration and reshapes tumour heterogeneity in Sézary syndrome.

BACKGROUND: Mogamulizumab, an anti-CCR4 monoclonal antibody, has been shown to increase progression-free survival in cutaneous T-cell lymphoma. OBJECTIVES: We hypothesized that besides the targeted depletion of Sézary cells (SCs), mogamulizumab may reshape the immune tumour microenvironment. METHODS: Both malignant and benign compartments from 26 patients with B2 stage Sézary syndrome before mogamulizumab initiation were prospectively analysed using KIR3DL2 and TCRVß markers, serological markers and molecular assessments of clonality. RESULTS: Prior to mogamulizumab, the benign subset of CD4+ T cells displayed exhausted phenotypes, with an increased gradient in programmed death-1, TIGIT, DNAM-1, CD27, CD28 and CD70 expression from age-matched controls to patients' benign CD4+ T cells and to SCs. All patients presented SCs with heterogeneous phenotypes, and differential expression of individual markers was found within distinct malignant subsets. Early complete blood response was observed in 17 of 26 patients and was associated with higher baseline CCR4 expression. A drastic decrease in benign T cells and activated regulatory T-cell counts was observed during the first 4 weeks. Long-term follow-up revealed the emergence of an immune restoration involving CD8+ and naive and stem memory CD4+ T cells, with almost complete disappearance of exhausted lymphocytes. Development of resistance or tumour escape to mogamulizumab was associated with the emergence of CCR4- SCs in blood and skin, displaying significant changes in their heterogeneity patterns, and not explained only by mutations within CCR4 coding regions. CONCLUSIONS: Mogamulizumab likely contributes to the restoration of efficient immunity and reshapes not only the malignant lymphocyte subset but also the benign subset. These results have potential implications for optimal therapeutic sequences and/or combinations. What is already known about this topic? Management of Sézary syndrome (SS) involves successive therapies that participate as cause and consequence in the emergence of resistant clones, on a background of immunodeficiency. We and others have reported the complex and dynamic heterogeneity of Sézary cells (SCs) during disease progression. Mogamulizumab therapy, by targeting the skin-homing receptor CCR4, mainly expressed by SCs, has been shown to increase progression-free survival in patients with SS. What does this study add? Using multicolour flow cytometry, we provide quantification of CCR4 and immune checkpoint molecules on malignant SCs and benign CD4+ T cells from patients with SS, separated using KIR3DL2 and TCRVß expression. Mogamulizumab is not only aimed at eradicating malignant SCs but potentially contributes to the restoration of efficient immunity. Tumour escape is associated with the emergence of CCR4- SCs, not explained only by mutations within CCR4 coding regions.

Surv-CRM-12: A Bayesian phase I/II survival CRM for right-censored toxicity endpoints with competing disease progression.

The growing interest in new classes of anti-cancer agents, such as molecularly-targeted therapies and immunotherapies with modes of action different from those of cytotoxic chemotherapies, has changed the dose-finding paradigm. In this setting, the observation of late-onset toxicity endpoints may be precluded by treatment and trial discontinuation due to disease progression, defining a competing event to toxicity. Trial designs where dose-finding is modeled in the framework of a survival competing risks model appear particularly well-suited. We aim to provide a phase I/II dose-finding design that allows dose-limiting toxicity (DLT) outcomes to be delayed or unobserved due to competing progression within the possibly long observation window. The proposed design named the Survival-continual reassessment method-12, uses survival models for right-censored DLT and progression endpoints. In this competing risks framework, cause-specific hazards for DLT and progression-free of DLT were considered, with model parameters estimated using Bayesian inference. It aims to identify the optimal dose (OD), by minimizing the cumulative incidence of disease progression, given an acceptable toxicity threshold. In a simulation study, design operating characteristics were evaluated and compared to the TITE-BOIN-ET design and a nonparametric benchmark approach. The performance of the proposed method was consistent with the complexity of scenarios as assessed by the nonparametric benchmark. We found that the proposed design presents satisfying operating characteristics in selecting the OD and safety.

Dose-finding design and benchmark for a right censored endpoint.

Dose-finding trials aim to determine a safe dose to be tested in larger trials for efficacy. In oncology, designs generally assume conventional monotonic increasing dose-toxicity relationships, mostly with binary outcomes (e.g., dose-limiting toxicity or not), measured in the first cycle of therapy or for a fixed number of cycles. However, with new anti-cancer agents such as molecularly targeted therapies and immunotherapies, late-onset toxicities have become more frequent. Designs with prolonged observation windows and censored endpoints analyzed using survival models, appear particularly suited to these settings. Moreover, in this setting, the observation of the late-onset toxicity endpoint could be precluded by trial discontinuation due to death, progression, patient withdrawal, or physician discretion, defining a competing event to toxicity. We propose extensions of the Continual Reassessment Method (CRM) dose-finding design using survival working models for right-censored endpoints and for handling treatment discontinuation in the toxicity observation window, namely the Survival-CRM (Surv-CRM) and the informative survival-CRM (iSurv-CRM). We also developed a benchmark approach for its evaluation. In a simulation study, we compared the performance of the Surv-CRM and iSurv-CRM, to those of the Time-to-event (TITE)-CRM and the nonparametric benchmark. The performance of the proposed methods was consistent with the complexity of scenarios as assessed by the nonparametric benchmark. Without treatment discontinuations, the Surv-CRM provides proportions of correct dose selection close to those of the TITE-CRM with fewer observed toxicities and patients assigned to overtoxic dose levels. In the presence of treatment discontinuation, the iSurv-CRM outperforms the TITE-CRM in identifying the correct dose level.

Lower Relapses Rate With Infliximab Versus Adalimumab in Sight-Threatening Uveitis: A Multicenter Study of 330 Patients.

PURPOSE: To compare the relapse rate of sight-threatening noninfectious uveitis (NIU) in patients treated with infliximab (IFX) or adalimumab (ADA). DESIGN: Observational retrospective multicenter study. METHODS: A total of 330 patients (median age, 36 years; interquartile range, 27-54), 45.2% men) with sight-threatening NIU (ie, retinal vasculitis and/or macular edema) treated with anti-tumor necrosis factor [TNF]-α agents (IFX intravenously at 5 mg/kg at weeks 0, 2, 6, and every 4 to 6 weeks or ADA subcutaneously at 80 mg, then 40 mg every 2 weeks). Data were obtained retrospectively from patients' medical records. Main outcome measures were relapse rate, complete response of NIU, corticosteroid sparing effect, and safety. RESULTS: Main etiologies of uveitis included Behçet disease (27%), idiopathic juvenile arthritis (5.8%), and sarcoidosis (5.5%). The estimated relapse rate at 6 months after introduction of biological agents was 13% (95% CI = 0.009-0.16). IFX was associated with less relapse risk than ADA (hazard ratio [HR] = 0.52, 95% CI = 0.36- 0.77, P = .001). ADA and IFX were comparable in terms of complete response rate of NIU as well as corticosteroid-sparing effect. Behçet disease was associated with higher odds of complete response (HR = 2.04, 95% CI = 1.16 -3.60, P = .01] and lower relapse rate (HR = 0.53, 95% CI = 0.33-0.85, P = .009) than other causes of NIU with anti-TNF-α agents. CONCLUSIONS: In sight-threatening NIU, IFX seems to be associated with a lower relapse rate than ADA.