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SummaryEfficacy of checkpoint inhibitor therapies in cancer varies greatly, with some patients showing complete responses while others do not respond and experience progressive disease. We aimed to identify correlates of response and progression following PD-1-directed therapy by immunophenotyping peripheral blood samples from 20 patients with advanced malignant melanoma before and after treatment with the PD-1 blocking antibody pembrolizumab. Our data reveal that individuals responding to PD-1 blockade were characterised by increased CD8 T cell proliferation following treatment, while progression was associated with an increase in CTLA-4-expressing Treg. Remarkably, unsupervised clustering analysis of pre-treatment T cell subsets revealed differences in individuals that went on to respond to PD-1 blockade compared to individuals that did not. These differences mapped to expression of the proliferation marker Ki67 and the costimulatory receptor CD28 as well as the inhibitory molecules 2B4 and KLRG1. While these results require validation in larger patient cohorts, they suggest that flow cytometric analysis of a relatively small number of T cell markers in peripheral blood could potentially allow stratification of PD-1 blockade treatment response prior to therapy initiation.

Pembrolizumab is an anti-programmed cell death protein 1 immune checkpoint inhibitor with a dosing schedule of 200 mg 3 weekly (q3w). Dose of 400 mg 6 weekly (q6w) was approved based on simulation of dose/exposure relationships and predicted no difference in toxicity. We present real-world comparative toxicity data. Patients receiving pembrolizumab for any indication between March and December 2019 were included across 3 regional centers. Toxicity data were collected retrospectively using Common Terminology Criteria for Adverse Events, v5.0. Clinically significant immune-related adverse events (CSirAE) were defined as immune-related events and grade ≥3 rash. Data were analyzed using incidence (Poisson distribution) and incidence ratio. Overall, 63 patients started on q6w and 110 patients received q3w. There were 3 (q6w) and 8 (q3w) grade 3-5 CSirAE and 13 (q6w) and 31 (q3w) grade 1-2 CSirAE. The incidence of grade 3-5 CSirAE was 0.77 (95% confidence interval: 0.16-2.24) per 100 patient-months in q6w and 0.68 (95% confidence interval: 0.29-1.34) per 100 patient-months in q3w (incidence ratio of 1.13; 95% confidence interval: 0.19-4.70). Low-grade toxicity was common (fatigue, pruritus, rash; q6w 46%, q3w 42%). Incidence of CSirAEs was low but low-grade toxicity was common. Despite a limited number of events, there is the suggestion that the q6w schedule has a similar toxicity profile to q3w and therefore consideration should be given to the reduced burden to patients and health services when deciding treatment.

Summary Background Systemic adjuvant treatment might mitigate the high risk of disease recurrence in patients with resected stage IIC–III melanoma. The BRIM8 study evaluated adjuvant vemurafenib monotherapy in patients with resected, BRAF V600 mutation-positive melanoma. Methods BRIM8 was a phase 3, international, double-blind, randomised, placebo-controlled study that enrolled 498 adults (aged ≥18 years) with histologically confirmed stage IIC–IIIA–IIIB (cohort 1) or stage IIIC (cohort 2) BRAF V600 mutation-positive melanoma that was fully resected. Patients were randomly assigned (1:1) by an interactive voice or web response system to receive twice-daily adjuvant oral vemurafenib 960 mg tablets or matching placebo for 52 weeks (13 × 28-day cycles). Randomisation was done by permuted blocks (block size 6) and was stratified by pathological stage and region in cohort 1 and by region in cohort 2. The investigators, patients, and sponsor were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population, evaluated separately in each cohort. Hierarchical analysis of cohort 2 before cohort 1 was prespecified. This trial is registered with ClinicalTrials.gov, number NCT01667419. Findings The study enrolled 184 patients in cohort 2 (93 were assigned to vemurafenib and 91 to placebo) and 314 patients in cohort 1 (157 were assigned to vemurafenib and 157 to placebo). At the time of data cutoff (April 17, 2017), median study follow-up was 33·5 months (IQR 25·9–41·6) in cohort 2 and 30·8 months (25·5–40·7) in cohort 1. In cohort 2 (patients with stage IIIC disease), median disease-free survival was 23·1 months (95% CI 18·6–26·5) in the vemurafenib group versus 15·4 months (11·1–35·9) in the placebo group (hazard ratio [HR] 0·80, 95% CI 0·54–1·18; log-rank p=0·026). In cohort 1 (patients with stage IIC–IIIA–IIIB disease) median disease-free survival was not reached (95% CI not estimable) in the vemurafenib group versus 36·9 months (21·4–not estimable) in the placebo group (HR 0·54 [95% CI 0·37–0·78]; log-rank p=0·0010); however, the result was not significant because of the prespecified hierarchical prerequisite for the primary disease-free survival analysis of cohort 2 to show a significant disease-free survival benefit. Grade 3–4 adverse events occurred in 141 (57%) of 247 patients in the vemurafenib group and 37 (15%) of 247 patients in the placebo group. The most common grade 3–4 adverse events in the vemurafenib group were keratoacanthoma (24 [10%] of 247 patients), arthralgia (17 [7%]), squamous cell carcinoma (17 [7%]), rash (14 [6%]), and elevated alanine aminotransferase (14 [6%]), although all keratoacanthoma events and most squamous cell carcinoma events were by default graded as grade 3. In the placebo group, grade 3–4 adverse events did not exceed 2% for any of the reported terms. Serious adverse events were reported in 40 (16%) of 247 patients in the vemurafenib group and 25 (10%) of 247 patients in the placebo group. The most common serious adverse event was basal cell carcinoma, which was reported in eight (3%) patients in each group. One patient in the vemurafenib group of cohort 2 died 2 months after admission to hospital for grade 3 hypertension; however, this death was not considered to be related to the study drug. Interpretation The primary endpoint of disease-free survival was not met in cohort 2, and therefore the analysis of cohort 1 showing a numerical benefit in disease-free survival with vemurafenib versus placebo in patients with resected stage IIC–IIIA–IIIB BRAF V600 mutation-positive melanoma must be considered exploratory only. 1 year of adjuvant vemurafenib was well tolerated, but might not be an optimal treatment regimen in this patient population. Funding F Hoffman–La Roche Ltd.

Background: Afatinib has demonstrated clinical benefit in patients with non-small-cell lung cancer progressing after treatment with erlotinib/gefitinib. This phase III trial prospectively assessed whether continued irreversible ErbB-family blockade with afatinib plus paclitaxel has superior outcomes versus switching to chemotherapy alone in patients acquiring resistance to erlotinib/gefitinib and afatinib monotherapy. Patients and methods: Patients with relapsed/refractory disease following ≥ 1 line of chemotherapy, and whose tumors had progressed following initial disease control (≥ 12 weeks) with erlotinib/gefitinib and thereafter afatinib (50 mg/day), were randomized 2:1 to receive afatinib plus paclitaxel (40 mg/day; 80 mg/m2/week) or investigator's choice of single-agent chemotherapy. The primary end point was progression-free survival (PFS). Other end points included objective response rate (ORR), overall survival (OS), safety and patient-reported outcomes. Results: Two hundred and two patients with progressive disease following clinical benefit from afatinib were randomized to afatinib plus paclitaxel (n ≥ 134) or single-agent chemotherapy (n ≥ 68). PFS (median 5.6 versus 2.8 months, hazard ratio 0.60, P ≥ 0.003) and ORR (32.1% versus 13.2%, P ≥ 0.005) significantly improved with afatinib plus paclitaxel. There was no difference in OS. Global health status/quality of life was maintained with afatinib plus paclitaxel over the entire treatment period. The median treatment duration was 133 and 51 days with afatinib plus paclitaxel and single-agent chemotherapy, respectively; 48.5% of patients receiving afatinib plus paclitaxel and 30.0% of patients receiving single-agent chemotherapy experienced drug-related grade 3/4 adverse events. Treatment-related adverse events were consistent with those previously reported with each agent. Conclusion: Afatinib plus paclitaxel improved PFS and ORR compared with single-agent chemotherapy in patients who acquired resistance to erlotinib/gefitinib and progressed on afatinib after initial benefit. LUX-Lung 5 is the first prospective trial to demonstrate the benefit of continued ErbB targeting post-progression, versus switching to single-agent chemotherapy. Trial registration number: NCT01085136 (clinicaltrials.gov).