Efficacy of TIL Therapy in Advanced Cutaneous Melanoma in the Current Immuno-oncology Era: Updated Systematic Review and Meta-analysis.

BACKGROUND: Adoptive cell therapy with tumor-infiltrating lymphocytes (TIL-ACT) has consistently shown efficacy in advanced melanoma. New results in the field provide now the opportunity to assess overall survival (OS) after TIL-ACT and to examine the effect of prior anti-PD-(L)1 therapy on its efficacy. METHODS: A comprehensive search was conducted in PubMed up to 29 February 2024. Ιn this meta-analysis we focused on studies including high-dose interleukin-2 (HD IL-2), doubling the patient numbers from our previous meta-analysis conducted up to December 20181 and using OS as the primary endpoint. Objective response rate (ORR), complete response rate (CRR) and duration of response (DOR) were secondary endpoints. Findings are synthesized using tables, Kaplan-Meier plots and forest plots. Pooled estimates for ORR and CRR were derived from fixed or random effect models. RESULTS: A total of 13 HD IL-2 studies were included in this updated meta-analysis, with OS information available for 617 patients. No difference was found in median OS between studies with prior anti-PD-(L)1 treatment [n=238; 17.5 months (95% confidence interval (CI):13.8-20.5)] and without [n=379; 16.3 months (95%CI:14.2-20.6)] (log-rank p=0.53). ORR was estimated to be 34% (95%CI:16%-52%) and 44% (95%CI:37%-51%), for the studies with and without prior anti-PD-(L)1, respectively. The pooled estimate for CRR was 10% for both groups. No statistically significant difference was observed between the two groups, either for ORR (p=0.15) or CRR (p=0.45). CONCLUSIONS: Prior anti-PD-(L)1 treatment has no effect on the clinical response or survival benefit from TIL-ACT in advanced cutaneous melanoma. The benefit of TIL therapy in the second-line setting is also present post anti-PD-(L)1 treatment. Our data reinforce the evidence that TIL-ACT should be considered as a treatment of choice in second-line for metastatic melanoma patients failing anti-PD-(L)1 therapy.

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.

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.