Duration of and time to response in oncology clinical trials from the perspective of the estimand framework.

Duration of response (DOR) and time to response (TTR) are typically evaluated as secondary endpoints in early-stage clinical studies in oncology when efficacy is assessed by the best overall response and presented as the overall response rate. Despite common use of DOR and TTR in particular in single-arm studies, the definition of these endpoints and the questions they are intended to answer remain unclear. Motivated by the estimand framework, we present relevant scientific questions of interest for DOR and TTR and propose corresponding estimand definitions. We elaborate on how to deal with relevant intercurrent events which should follow the same considerations as implemented for the primary response estimand. A case study in mantle cell lymphoma illustrates the implementation of relevant estimands of DOR and TTR. We close the paper with practical recommendations to implement DOR and TTR in clinical study protocols.

[Response characteristics of tislelizumab combined with chemotherapy in first-line treatment of locally advanced or metastatic non-squamous non-small cell lung cancer].

Objective: To investigate the response characteristics of patients with locally advanced/metastatic non-squamous non-small cell lung cancer (nsq-NSCLC) treated with tislelizumab in combination with chemotherapy in the first line. Methods: Patients with nsq-NSCLC who achieved complete or partial remission after treatment with tislelizumab in combination with chemotherapy or chemotherapy alone in the RATIONALE 304 study, as assessed by an independent review board, were selected to analyze the response characteristics and safety profile of the responders. Time to response (TTR) was defined as the time from randomization to the achievement of first objective response. Depth of response (DpR) was defined as the maximum percentage of tumor shrinkage compared with the sum of the baseline target lesion length diameters. Results: As of January 23, 2020, 128 patients treated with tislelizumab in combination with chemotherapy achieved objective tumor response (responders), representing 57.4%(128/223) of the intention-to-treat population, with a TTR of 5.1 to 33.3 weeks and a median TTR of 7.9 weeks. Of the responders (128), 50.8%(65) achieved first remission at the first efficacy assessment (week 6), 31.3%(40) at the second efficacy assessment (week 12), and 18.0%(23) at the third and subsequent tumor assessments. The percentages of responders who achieved a depth of tumor response of 30% to <50%, 50% to <70% and 70% to 100% were 45.3%(58/128), 28.1%(36/128) and 26.6%(34/128), respectively, with median progression-free survival (PFS) of 9.0 months (95% CI: 7.7 to 9.9 months), 11.5 months (95% CI: 7.7 months to not reached) and not reached (95% CI: 11.8 months to not estimable), respectively. Tislelizumab plus chemotherapy were generally well tolerated in responders with similar safety profile to the overall safety population. Conclusion: Among responders to tislelizumab in combination with chemotherapy for nsq-NSCLC, 82.0%(105/128) achieves response within the first two tumor assessments (12 weeks) and 18.0%(23/128) achieves response at later (18 to 33 weeks) assessments, and there is a trend toward prolonged PFS in responders with deeper tumor response.

Rapid Response to Vedolizumab Therapy in Biologic-Naive Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Vedolizumab, a humanized monoclonal antibody against α4ß7 integrin, is used to treat adults with moderately to severely active ulcerative colitis (UC) and Crohn's disease (CD). We investigated the time course of clinical response to vedolizumab in patients who were and were not previously treated with tumor necrosis factor (TNF) antagonists. METHODS: We performed a post-hoc analysis of data from phase 3, randomized, controlled trials of vedolizumab vs placebo in adult patients with UC (N = 374) or CD (N = 784). We collected data on patient-reported symptoms (rectal bleeding and stool frequency for patients with UC, abdominal pain and loose stool frequency for patients with CD) reported at weeks 2, 4, and 6 of treatment. We reported mean percentage score changes from baseline and proportions of patients who achieved predefined scores. We performed multivariate logistic regression analysis to identify factors associated with an early response (at week 2). RESULTS: In patients with UC (overall or naive to TNF antagonist therapy), a significantly greater percentage of patients given vedolizumab achieved the predefined composite symptom score at weeks 2, 4, and 6 compared to those given placebo. In patients with CD who were naive to TNF antagonists, a significantly greater percentage of patients given vedolizumab achieved the predefined score at weeks 2 and 4 compared to those given placebo. Among patients with UC given vedolizumab, 19.1% (overall) and 22.3% (TNF antagonist naive) achieved a composite score of rectal bleeding of 0 and stool frequency ≤1 at week 2 compared to 10% (overall) and 6.6% (TNF antagonist naive) of those receiving placebo. Among TNF antagonist-naive patients with CD, 15.0% of those given vedolizumab achieved an average daily composite score of abdominal pain ≤1 and loose stool frequency ≤3 at week 2 (compared to 7.9% given placebo), and 23.8% of those given vedolizumab achieved these by week 4 (compared to 10.3% given placebo). CONCLUSIONS: In a post-hoc analysis of data from phase 3 clinical trials, vedolizumab significantly improved patient-reported symptoms of UC and CD as early as week 2 of treatment, continuing through the first 6 weeks-especially when given as first-line biologic therapy. ClinicalTrials.gov no: NCT00783718, NCT00783692, NCT01224171.

Treat to target in Crohn's disease: A practical guide for clinicians.

A treat-to-target (T2T) approach applies the principles of early intervention and tight disease control to optimise long-term outcomes in Crohn's disease. The Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE)-II guidelines specify short, intermediate, and long-term treatment goals, documenting specific treatment targets to be achieved at each of these timepoints. Scheduled appraisal of Crohn's disease activity against pre-defined treatment targets at these timepoints remains central to determining whether current therapy should be continued or modified. Consensus treatment targets in Crohn's disease comprise combination clinical and patient-reported outcome remission, in conjunction with biomarker normalisation and endoscopic healing. Although the STRIDE-II guidelines endorse the pursuit of endoscopic healing, clinicians must consider that this may not always be appropriate, acceptable, or achievable in all patients. This underscores the need to engage patients at the outset in an effort to personalise care and individualise treatment targets. The use of non-invasive biomarkers such as faecal calprotectin in conjunction with cross-sectional imaging techniques, particularly intestinal ultrasound, holds great promise; as do emerging treatment targets such as transmural healing. Two randomised clinical trials, namely, CALM and STARDUST, have evaluated the efficacy of a T2T approach in achieving endoscopic endpoints in patients with Crohn's disease. Findings from these studies reflect that patient subgroups and Crohn's disease characteristics likely to benefit most from a T2T approach, remain to be clarified. Moreover, outside of clinical trials, data pertaining to the real-world effectiveness of a T2T approach remains scare, highlighting the need for pragmatic real-world studies. Despite the obvious promise of a T2T approach, a lack of guidance to support its integration into real-world clinical practice has the potential to limit its uptake. This highlights the need to describe strategies, processes, and models of care capable of supporting the integration and execution of a T2T approach in real-world clinical practice. Hence, this review seeks to examine the current and emerging literature to provide clinicians with practical guidance on how to incorporate the principles of T2T into routine clinical practice for the management of Crohn's disease.

Duration of initial prednisolone therapy for first episode of childhood nephrotic syndrome based on time to response.

Background: The duration of initial corticosteroid therapy in newly diagnosed Idiopathic nephrotic syndrome (INS) is about 3 months. Our study was designed to test the feasibility of a shorter duration of corticosteroid therapy in newly diagnosed INS who show a quicker response. Methods: Patients who responded within 10 days (Group A) received 8 weeks of corticosteroid therapy as compared to 12-14 weeks of standard therapy in those who responded between >10 days to 28 days (Group B), and follow up for 52 weeks. The primary endpoint is time to first relapse after treatment completion. (NCT03878914, March 18, 2019). Results: A total of 33 children with INS were enrolled and the follow-up data were analyzed. The clinical and laboratory characteristics of patients in both groups were similar. No significant difference was found in time to first relapse [65(14.5, 159) days for Group A vs. 28(17, 61.5) days for Group B, P = 0.371], the incidence of frequently relapsing nephrotic syndrome [6/18 (33.3%) vs. 5/10(50%), P = 0.644] or requirement for alternative immunosuppressant [4/18 (22.2%) vs. 1/10 (10%), P = 0.769]. Group A received similar corticosteroid dose compare with Group B (3511 ± 2421 mg/m2 vs. 4117 ± 2556 mg/m2, P = 0.524). Frequency and severity of corticosteroid-related complications was similar in both groups. Conclusions: The time to first relapse and the number of relapses per patient were comparable between the two groups. However, more patients in Group A relapsed and the mean total dose of prednisolone for the study period was very similar between the two groups.

Response Efficacy of PD-1 and PD-L1 Inhibitors in Clinical Trials: A Systematic Review and Meta-Analysis.

BACKGROUND: Immune checkpoint inhibitors targeting the PD-1/PD-L1 pathway have demonstrated promise in treating a variety of advanced cancers; however, little is known regarding their efficacy under various clinical situations, including different cancer types, treatment lines, drug combinations, and therapeutic regimens. METHODS: Published articles and conference abstracts (in English) in PubMed, Embase, the Cochrane Central Register, and Web of Science were searched up to February 10, 2020. The data were analyzed by the meta-analysis program in Stata. RESULTS: A total of 16,400 patients from 91 clinical trials were included in this meta-analysis. PD-1/PD-L1 inhibitors had a mean ORR of 19.56% (95% CI: 15.09-24.03), a median TTR of 2.05 months (m) (95%CI: 1.85-2.26), and a median DOR of 10.65 m (95%CI: 7.78-13.52). First-line treatment had a higher ORR (36.57% vs. 13.18%) but a shorter DOR (9.00 m vs. 13.42 m) compared to the second-line or subsequent treatment. Immunotherapy combined with chemotherapy (I+C) (46.81% [95%CI: 36.02-57.60]) had a statistically significant higher ORR compared to immunotherapy (I) (17.75% [95%CI: 14.47-21.03]) or immunotherapy combined with immunotherapy (I+O) (12.25% [95%CI: 1.56-22.94]), while I+C (8.09 m [95%CI: 6.86-9.32]) appeared to reduce the DOR compared to I (12.39 m [95%CI: 7.60-17.18]). PD-1 inhibitors were associated with better ORR (21.65% vs. 17.60%) and DOR (11.26 m vs. 10.03 m) compared to PD-L1 inhibitors. There were no significant differences in TTR under different situations. CONCLUSIONS: PD-1/PD-L1 inhibitors were promising immunotherapeutic agents to achieve satisfactory response efficacies with different cancer types, treatment lines, drug combinations, and therapeutic regimens. This comprehensive summary of the response efficacy of PD-1/PD-L1 inhibitors serves as a reference for clinicians to make evidence-based decisions.

Timing in combination with radiotherapy and patterns of disease progression in non-small cell lung cancer treated with EGFR-TKI.

OBJECTIVES: Tyrosine kinase inhibitor (TKI) has been the standard of care for advanced non-small cell lung cancers (NSCLC) harboring epidermal growth factor receptor (EGFR) mutation, but these tumors invariably develop drug resistance. As progression most frequently advances in sites of original disease, our study sought to explore the time to response for NSCLC to TKI therapy and the patterns of disease progression, to provide evidence for timing and candidates for local therapy intervention. MATERIALS AND METHODS: A cohort of 105 EGFR-mutated IIIB or IV NSCLC patients treated with EGFR-TKI were retrospectively analyzed. The disease progression patterns were divided into 3 categories: progression in sites of original disease, progression in new distant sites, and combined progression. RESULTS: Before cut-off date, 80 patients had disease progression. Thirty-three (41.25 %) patients had progression in sites of original disease, 34 (42.5 %) patients had progression in new sites and 13 (16.25 %) patients had combined progression, respectively. The median time to response for responders was 2.00 months (95 %CI 1.28-2.92 months), and the median time to maximal tumor shrinkage for SD patients was 2.00 months (95 %CI 1.42-2.58 months). Multivariate logistic regression model showed that the 21 exon mutation is related to the incidence of original site failure. CONCLUSION: Over 1/3 of the patients progress at the original sites, which indicated that this subset of patients may benefit from local therapy. Moreover, as the results indicate that considerable shrinkage for TKI therapy occurs in first two months after TKI initiation, local therapy can be adopted after this timepoint, before disease progression. We also propose EGFR gene mutation type as potential inclusion criteria to identify candidates for combined local therapy.

Time To Response In Patients With Advanced Anaplastic Lymphoma Kinase (ALK)-Positive Non-Small-Cell Lung Cancer (NSCLC) Receiving Alectinib In The Phase II NP28673 And NP28761 Studies.

INTRODUCTION: Alectinib is a highly selective and potent ALK inhibitor, approved for the treatment of patients with metastatic ALK+ NSCLC based on results from the Phase II global NP28673 (NCT01801111) and North American NP28761 (NCT01871805) studies. METHODS: This exploratory analysis of two Phase II studies of alectinib (NP28673/NP28761) investigated time to systemic response (TTR) and time to central nervous system (CNS) response (TTCR) in patients with previously treated advanced anaplastic lymphoma kinase fusion gene-positive (ALK+) non-small-cell lung cancer. Patients (n=225) received 600 mg oral alectinib twice daily and had scans every 6/8 weeks (NP28673/NP28761). RESULTS: For NP28673 and NP28761, respectively: median follow-up was 21.3 months/17.0 months; most responders (72.6%/82.9%) responded by the first disease assessment; median TTR was 8 weeks (95% confidence interval [CI]: 8.00-8.14)/6 weeks (95% CI: 5.86-6.14); median TTCR in responders with measurable baseline CNS disease was 8 weeks (95% CI: 7.86-10.29)/6 weeks (95% CI: 5.71-not evaluable). Similar results were observed regardless of measurable/non-measurable disease. DISCUSSION: These data suggest that alectinib achieves a rapid response in patients, both systemically and in the CNS.

Time to response with sodium oxybate for the treatment of excessive daytime sleepiness and cataplexy in patients with narcolepsy.

STUDY OBJECTIVES: This post hoc analysis evaluated the time to response that can be expected with sodium oxybate (SXB) for treatment of excessive daytime sleepiness (EDS) and cataplexy in patients with narcolepsy. METHODS: Data were from a 4-week, double-blind, randomized, placebo-controlled trial (GHB-2; N = 136) of oral SXB 3 g, 6 g, and 9 g nightly, and its 12-month open-label extension (GHB-3). Two response definitions were utilized: ≥ 20% improvement in Epworth Sleepiness Scale (ESS) score (EDS responders), and ≥ 50% reduction in weekly cataplexy attacks (cataplexy responders). These thresholds were previously determined to be clinically relevant based on analysis of the relationship of Clinical Global Impression of Change with ESS and number of cataplexy attacks. Kaplan-Meier curves and median times to first response, based on above criteria, and to maximum response were estimated. RESULTS: Among 86 patients randomized to SXB in GHB-2 and continued into GHB-3, 77.6% and 90.7% were EDS and cataplexy responders, respectively. The median (95% CI) times to first response were 37 (31-50) days for EDS and 25 (17-29) days for cataplexy, and median times to maximum response were 106 (85-164) days for EDS and 213 (94-279) days for cataplexy. GHB-3 results among 31 patients initially randomized to placebo were consistent with those treated with SXB throughout, but with longer times to maximum response. CONCLUSIONS: Response onset, assessed as clinically meaningful improvements in EDS and cataplexy, was observed in most patients within 2 months; a longer period is needed to achieve maximum response. Clinicians should recognize that time to initial and maximum response may take weeks to months.