Efficacy of adoptive therapy with tumor-infiltrating lymphocytes and recombinant interleukin-2 in advanced cutaneous melanoma: a systematic review and meta-analysis

Adoptive cell therapy (ACT) using autologous tumor-infiltrating lymphocytes (TIL) has been tested in advanced melanoma patients at various centers. We conducted a systematic review and meta-analysis to assess its efficacy on previously treated advanced metastatic cutaneous melanoma. The PubMed electronic database was searched from inception to 17 December 2018 to identify studies administering TIL-ACT and recombinant interleukin-2 (IL-2) following non-myeloablative chemotherapy in previously treated metastatic melanoma patients. Objective response rate (ORR) was the primary end point. Secondary end points were complete response rate (CRR), overall survival (OS), duration of response (DOR) and toxicity. Pooled estimates were derived from fixed or random effect models, depending on the amount of heterogeneity detected. Analysis was carried out separately for high dose (HD) and low dose (LD) IL-2. Sensitivity analyses were carried out. Among 1211 records screened, 13 studies (published 1988 - 2016) were eligible for meta-analysis. Among 410 heavily pretreated patients (some with brain metastasis), 332 received HD-IL-2 and 78 LD-IL-2. The pooled overall ORR estimate was 41% [95% confidence interval (CI) 35% to 48%], and the overall CRR was 12% (95% CI 7% to 16%). For the HD-IL-2 group, the ORR was 43% (95% CI 36% to 50%), while for the LD-IL-2 it was 35% (95% CI 25% to 45%). Corresponding pooled estimates for CRR were 14% (95% CI 7% to 20%) and 7% (95% CI 1% to 12%). The majority of HD-IL-2 complete responders (27/28) remained in remission during the extent of follow-up after CR (median 40 months). Sensitivity analyses yielded similar results. Higher number of infused cells was associated with a favorable response. The ORR for HD-IL-2 compared favorably with the nivolumab/ipilimumab combination following anti-PD-1 failure. TIL-ACT therapy, especially when combined with HD-IL-2, achieves durable clinical benefit and warrants further investigation. We discuss the current position of TIL-ACT in the therapy of advanced melanoma, particularly in the era of immune checkpoint blockade therapy, and review future opportunities for improvement of this approach.

6082A prospective, multicenter, nationwide, observational study of flecainide controlled release on the quality of life of patients with atrial fibrillation in Greece, the REFLEC-CR study

Background/Introduction

Atrial fibrillation (AF) is the most common cardiac arrhythmia with a considerable impact on patients' quality of life (QoL). Flecainide acetate, is a class Ic antiarrhythmic agent, recommended as first line treatment in AF patients without underlying structural heart disease.

Purpose

This prospective, multicenter, nationwide, observational study aimed to evaluate the effect of oral treatment with controlled-release (CR) flecainide administered once daily on AF patients' QoL and treatment compliance during a 12-week period.

Methods

A total of 70 cardiologists participated in the study enrolling consecutive adult patients with paroxysmal or persistent AF, treated with flecainide CR in the context of a rhythm control strategy. The effect on QoL was assessed by the Canadian Cardiovascular Society Severity of Atrial Fibrillation scale (CCS-SAF) measured at baseline and at 12 weeks of treatment.

Results

In total, 679 patients (53.2% females, mean age 65.9±11.7 years, 86.9% paroxysmal AF) were included in the analysis. At least one prior antiarrhythmic treatment was documented in 43.8% of patients. The initial daily dose of flecainide CR was 100mg in 71.7% of the patients, with a titration to 200mg by the end of study achieved in 67%. In 93.6% of patients an excellent compliance score (100%) to treatment was recorded at the end of the study period. Treatment with flecainide CR resulted in a significant improvement in QoL as presented in the table.

Table 1 CCS-SAF score Baseline (Week 0) End of study visit (Week 12) N=679 N=634 Class 1 (minimal effect on QoL) 343 (50.5) 464 (73.2) Class 2 (minor effect on QoL) 253 (37.2) 140 (22.1) Class 3 (moderate effect on QoL) 73 (10.8) 28 (4.4) Class 4 (severely impairs QoL) 10 (1.5) 2 (0.3) CCS-SAF continuous score   Mean ± SD 1.64±0.73 1.32±0.57 Change from baseline‡   Mean (95% CI) −0.325 (−0.379, −0.271)   p-value <0.0001 ‡Paired t-test is used.

Conclusions

This prospective, multicenter, observational study demonstrated that treatment of AF patients with flecainide CR, was associated with a significant improvement of QoL and excellent compliance to treatment.

Acknowledgement/Funding

Sponsored by WinMedica S.A.

Abstract P5-18-02: Selective Crossover in Randomized Trials of Adjuvant Trastuzumab for Breast Cancer: Coping with Success

BACKGROUND: Disease-free survival (DFS) is often a primary endpoint of randomized trials of adjuvant therapies for breast cancer, but long-term follow-up of DFS and especially overall survival (OS) remain important. When the primary DFS results favor the experimental arm, patients (pts) assigned to the control group may select the option to crossover to receive the experimental treatment via protocol amendment. Such “selective crossover” disturbs the integrity of the randomized comparison for any efficacy endpoints that rely on further follow-up. Selective crossover, which is motivated by positive results having been observed in the current trial, is distinct from so-called “unplanned crossover,” which refers to non-adherence to protocol. In this abstract, we discuss the consequences of selective crossover for trials evaluating adjuvant trastuzumab, using the HERA (HERceptin Adjuvant) trial as an example, and present a variety of alternative analysis approaches.

METHODS: HERA enrolled 5102 women with HER2-positive early breast cancer who had completed all surgery and (neo)adjuvant chemotherapy to compare 1 or 2 years of trastuzumab treatment vs observation. After a positive first interim analysis at 1y median follow-up (MFU) showed that 1 year of trastuzumab significantly improved DFS vs observation [MJ Piccart-Gebhart et al; NEJM 2005], event-free patients in the observation group were offered crossover to receive trastuzumab. 885 (52%) of the 1698 pts in the observation group selectively crossed over to trastuzumab.

RESULTS: Previously reported intention-to-treat (ITT) analysis of HERA at 4y MFU showed a decreasing effectiveness of trastuzumab with respect to DFS compared with those at 2y MFU [L Gianni et al, Lancet Oncol 2011; I Smith et al, Lancet 2007]. In addition, the ITT analysis of OS at 4y MFU showed little effect of trastuzumab, while the analysis artificially censoring follow-up in the observation group at the time of selective crossover showed a substantial OS advantage for trastuzumab.

Bayesian analysis of the differences of count data

Paired count data usually arise in medicine when before and after treatment measurements are considered. In the present paper we assume that the correlated paired count data follow a bivariate Poisson distribution in order to derive the distribution of their difference. The derived distribution is shown to be the same as the one derived for the difference of the independent Poisson variables, thus recasting interest on the distribution introduced by Skellam. Using this distribution we remove correlation, which naturally exists in paired data, and we improve the quality of our inference by using exact distributions instead of normal approximations. The zero-inflated version is considered to account for an excess of zero counts. Bayesian estimation and hypothesis testing for the models considered are discussed. An example from dental epidemiology is used to illustrate the proposed methodology.