Pembrolizumab versus placebo as post-nephrectomy adjuvant therapy for clear cell renal cell carcinoma (KEYNOTE-564): 30-month follow-up analysis of a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

The first interim analysis of the KEYNOTE-564 study showed improved disease-free survival with adjuvant pembrolizumab compared with placebo after surgery in patients with clear cell renal cell carcinoma at an increased risk of recurrence. The analysis reported here, with an additional 6 months of follow-up, was designed to assess longer-term efficacy and safety of pembrolizumab versus placebo, as well as additional secondary and exploratory endpoints.

METHODS

In the multicentre, randomised, double-blind, placebo-controlled, phase 3 KEYNOTE-564 trial, adults aged 18 years or older with clear cell renal cell carcinoma with an increased risk of recurrence were enrolled at 213 hospitals and cancer centres in North America, South America, Europe, Asia, and Australia. Eligible participants had an Eastern Cooperative Oncology Group performance status of 0 or 1, had undergone nephrectomy 12 weeks or less before randomisation, and had not received previous systemic therapy for advanced renal cell carcinoma. Participants were randomly assigned (1:1) via central permuted block randomisation (block size of four) to receive pembrolizumab 200 mg or placebo intravenously every 3 weeks for up to 17 cycles. Randomisation was stratified by metastatic disease status (M0 vs M1), and the M0 group was further stratified by ECOG performance status and geographical region. All participants and investigators involved in study treatment administration were masked to the treatment group assignment. The primary endpoint was disease-free survival by investigator assessment in the intention-to-treat population (all participants randomly assigned to a treatment). Safety was assessed in the safety population, comprising all participants who received at least one dose of pembrolizumab or placebo. As the primary endpoint was met at the first interim analysis, updated data are reported without p values. This study is ongoing, but no longer recruiting, and is registered with ClinicalTrials.gov, NCT03142334.

FINDINGS

Between June 30, 2017, and Sept 20, 2019, 994 participants were assigned to receive pembrolizumab (n=496) or placebo (n=498). Median follow-up, defined as the time from randomisation to data cutoff (June 14, 2021), was 30·1 months (IQR 25·7-36·7). Disease-free survival was better with pembrolizumab compared with placebo (HR 0·63 [95% CI 0·50-0·80]). Median disease-free survival was not reached in either group. The most common all-cause grade 3-4 adverse events were hypertension (in 14 [3%] of 496 participants) and increased alanine aminotransferase (in 11 [2%]) in the pembrolizumab group, and hypertension (in 13 [3%] of 498 participants) in the placebo group. Serious adverse events attributed to study treatment occurred in 59 (12%) participants in the pembrolizumab group and one (<1%) participant in the placebo group. No deaths were attributed to pembrolizumab.

INTERPRETATION

Updated results from KEYNOTE-564 support the use of adjuvant pembrolizumab monotherapy as a standard of care for participants with renal cell carcinoma with an increased risk of recurrence after nephrectomy.

FUNDING

Merck Sharp & Dohme LLC, a subsidiary of Merck & Co, Inc, Rahway, NJ, USA.

Ramucirumab with cisplatin and fluoropyrimidine as first-line therapy in patients with metastatic gastric or junctional adenocarcinoma (RAINFALL): a double-blind, randomised, placebo-controlled, phase 3 trial

BACKGROUND

VEGF and VEGF receptor 2 (VEGFR-2)-mediated signalling and angiogenesis can contribute to the pathogenesis and progression of gastric cancer. We aimed to assess whether the addition of ramucirumab, a VEGFR-2 antagonist monoclonal antibody, to first-line chemotherapy improves outcomes in patients with metastatic gastric or gastro-oesophageal junction adenocarcinoma.

METHODS

For this double-blind, randomised, placebo-controlled, phase 3 trial done at 126 centres in 20 countries, we recruited patients aged 18 years or older with metastatic, HER2-negative gastric or gastro-oesophageal junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and adequate organ function. Eligible patients were randomly assigned (1:1) with an interactive web response system to receive cisplatin (80 mg/m2, on the first day) plus capecitabine (1000 mg/m2, twice daily for 14 days), every 21 days, and either ramucirumab (8 mg/kg) or placebo on days 1 and 8, every 21 days. 5-Fluorouracil (800 mg/m2 intravenous infusion on days 1-5) was permitted in patients unable to take capecitabine. The primary endpoint was investigator-assessed progression-free survival, analysed by intention to treat in the first 508 patients. We did a sensitivity analysis of the primary endpoint, including a central review of CT scans. Overall survival was a key secondary endpoint. This study is registered with ClinicalTrials.gov, number NCT02314117.

FINDINGS

Between Jan 28, 2015, and Sept 16, 2016, 645 patients were randomly assigned to receive ramucirumab plus fluoropyrimidine and cisplatin (n=326) or placebo plus fluoropyrimidine and cisplatin (n=319). Investigator-assessed progression-free survival was significantly longer in the ramucirumab group than the placebo group (hazard ratio [HR] 0·753, 95% CI 0·607-0·935, p=0·0106; median progression-free survival 5·7 months [5·5-6·5] vs 5·4 months [4·5-5·7]). A sensitivity analysis based on central independent review of the radiological images did not corroborate the investigator-assessed difference in progression-free survival (HR 0·961, 95% CI 0·768-1·203, p=0·74). There was no difference in overall survival between groups (0·962, 0·801-1·156, p=0·6757; median overall survival 11·2 months [9·9-11·9] in the ramucirumab group vs 10·7 months [9·5-11·9] in the placebo group). The most common grade 3-4 adverse events were neutropenia (85 [26%] of 323 patients in the ramucirumab group vs 85 [27%] of 315 in the placebo group), anaemia (39 [12%] vs 44 [14%]), and hypertension (32 [10%] vs 5 [2%]). The incidence of any-grade serious adverse events was 160 (50%) of 323 patients in the ramucirumab group and 149 (47%) of 315 patients in the placebo group. The most common serious adverse events were vomiting (14 [4%] in the ramucirumab group vs 21 [7%] in the placebo group) and diarrhoea (11 [3%] vs 19 [6%]). There were seven deaths in each group, either during study treatment or within 30 days of discontinuing study treatment, which were the result of treatment-related adverse events. In the ramucirumab group, these adverse events were acute kidney injury, cardiac arrest, gastric haemorrhage, peritonitis, pneumothorax, septic shock, and sudden death (n=1 of each). In the placebo group, these adverse events were cerebrovascular accident (n=1), multiple organ dysfunction syndrome (n=2), pulmonary embolism (n=2), sepsis (n=1), and small intestine perforation (n=1).

INTERPRETATION

Although the primary analysis for progression-free survival was statistically significant, this outcome was not confirmed in a sensitivity analysis of progression-free survival by central independent review, and did not improve overall survival. Therefore, the addition of ramucirumab to cisplatin plus fluoropyrimidine chemotherapy is not recommended as first-line treatment for this patient population.

FUNDING

Eli Lilly and Company.

RAINFALL: A randomized, double-blind, placebo-controlled phase III study of cisplatin (Cis) plus capecitabine (Cape) or 5FU with or without ramucirumab (RAM) as first-line therapy in patients with metastatic gastric or gastroesophageal junction (G-GEJ) adenocarcinoma

5

Background: Ramucirumab, a VEGFR-2 IgG1 human monoclonal antibody, is the only biologic with proven efficacy as both a single-agent and in combination with paclitaxel in the second-line treatment of G-GEJ adenocarcinoma. RAINFALL (NCT02314117) is a global, double-blind, placebo-controlled randomized clinical trial addressing the hypothesis that adding ramucirumab to first-line Cis plus Cape or 5-fluorouracil (5FU) produces significant clinical benefit. Methods: Metastatic G-GEJ cancer patients eligible for first-line chemotherapy with ECOG performance status 0-1 were randomized 1:1 to receive either RAM (8 mg/kg iv D1, D8) or placebo (PL), every 21d. All patients received Cape (or 5FU)+Cis. Cis was given for up to 6 cycles. Cape+RAM/placebo was continued until progressive disease, toxicity or other discontinuation criteria. The primary endpoint was progression-free survival (PFS) for the first 508 patients; overall survival (OS) for ITT population was a powered secondary endpoint. Results: 645 patients were randomized to receive RAM+Cape/Cis (n=326) or PL+Cape/Cis (n=319). PFS was significantly prolonged in patients treated with RAM+Cape/Cis versus PL+Cape/Cis (HR, 0.75; 95% CI 0.61–0.94; p=0.011; median, 5.7 vs 5.4 mos), meeting the primary endpoint. There was no survival benefit for patients treated with RAM+Cape/Cis versus PL+Cape/Cis (HR, 0.96; 95% CI 0.80–1.16; p=0.68; median, 11.2 vs 10.7 mos). ORR in the ITT population was 41.1% in the RAM arm (95% CI 35.8–46.4) and 36.4% (95% CI 31.1–41.6) in the PL arm. Grade ≥3 adverse events in ≥10% of patients in the RAM arm were: neutropenia (26.3% RAM; 27.0% PL), anemia (12.1% RAM; 14.0% PL), and hypertension (9.9% RAM; 1.6% PL). No new safety signals were observed. Conclusions: In treatment-naïve patients with metastatic G-GEJ adenocarcinoma, the addition of ramucirumab to first-line chemotherapy conferred a significant 25% reduction in the risk of disease progression or death in the primary endpoint of PFS; however, ramucirumab was not associated with an improved OS. Clinical trial information: NCT02314117.

CheckMate 649: A randomized, multicenter, open-label, phase III study of nivolumab (NIVO) + ipilimumab (IPI) or nivo + chemotherapy (CTX) versus CTX alone in patients with previously untreated advanced (Adv) gastric (G) or gastroesophageal junction (GEJ) cancer

TPS192

Background: Pts with adv G/GEJ cancer have an OS of ≈ 1 y, indicating an unmet medical need for new first-line treatments. Expression of PD-L1 is observed in up to 40% of pts with G/GEJ cancer and is associated with poor prognosis. In the randomized phase 3 ATTRACTION-2 study, NIVO demonstrated superior overall survival vs placebo with a 38% reduction of the risk of death (median OS, 5.3 vs 4.1 mo; HR, 0.62 P< 0.0001) and increased the OS rate at 12 mo (27% vs 12%; Boku N et al ESMO 2017) in pts with adv CTX-R (≥ 2 lines) G/GEJ cancer. In the phase 1/2 CheckMate-032 study in pts with CTX-R G/GEJ/esophageal cancer (79% ≥ 2 prior Tx lines), NIVO 1 mg/kg + IPI 3 mg/kg had a manageable safety profile and resulted in 24% ORR (40% ORR in pts with PD-L1+ tumors), a median OS of 6.9 mo, and a 35% OS rate at 12 mo (Janjigian Y et al ASCO 2017). In the phase 1 CheckMate-012 trial, NIVO + CTX had clinical activity and manageable safety in pts with NSCLC (Rizvi NA et al J Clin Oncol 2016). These positive results support investigation of NIVO, NIVO + IPI, and NIVO + CTX in earlier lines of treatment for G/GEJ cancer. The open-label, phase 3 CheckMate 649 trial will evaluate NIVO + IPI and NIVO + CTX vs CTX alone as first-line treatment for pts with adv G/GEJ cancer (NCT02872116). Methods: 1266 pts aged ≥ 18 y with untreated, inoperable adv/metastatic G/GEJ cancer (histologically confirmed adenocarcinoma) regardless of PD-L1 status will be randomized to receive either NIVO + IPI, NIVO + CTX (capecitabine/oxaliplatin [XELOX] or fluorouracil/leucovorin/oxaliplatin [FOLFOX]), or investigator choice of XELOX or FOLFOX. Tumor tissue for determination of PD-L1 status (Dako assay) must be provided from ≤ 6 mo before study treatment. No prior systemic treatment, including HER2 inhibitors, are allowed. Pts with known HER2+ status, suspected autoimmune disease, grade > 1 peripheral neuropathy, or active infection are excluded. Primary endpoint is OS in pts with PD-L1+ (≥ 1%) tumors. Other endpoints include OS in all pts; PFS and time to symptom deterioration in all pts and in pts with PD-L1+ tumors; and safety. Clinical trial information: NCT02872116.

CheckMate 577: A randomized, double-blind, phase 3 study of adjuvant nivolumab (nivo) or placebo in pts with resected esophageal (E) or gastroesophageal junction (GEJ) cancer

TPS4131

Background: Expression of the PD-1 ligands PD-L1 and PD-L2 has been reported in ≈ 40% of pts with E/GEJ cancer and is associated with a poor prognosis. In a phase 3 trial, the PD-1 inhibitor nivo demonstrated an OS benefit vs placebo (HR, 0.63; P < 0.0001), resulting in a 37% reduction in the risk of death and double the OS rate at 12 mo (27% vs 11%) in pts with advanced gastric (G)/GEJ cancer refractory to ≥ 2 lines of chemotherapy (Kang YK, et al. J Clin Oncol. 2017;35 (suppl 4S) [abstract 2]). In this study, nivo was well tolerated, with a safety profile comparable with that of the placebo arm. These results indicate that nivo could be a new standard of care (SOC) for pts with heavily pretreated advanced G/GEJ cancer and provide a strong rationale to explore nivo in earlier lines of treatment for G/E/GEJ cancer. Currently, no effective adjuvant SOC is available after chemoradiotherapy (CRT) followed by resection for pts with E/GEJ cancer. This multinational, double-blind, phase 3 trial will evaluate nivo as an adjuvant therapy for pts with resected E/GEJ cancer (CheckMate 577; NCT02743494). Methods: In this study, an estimated 760 pts aged ≥ 18 years with stage II/III E/GEJ cancer are randomized to receive nivo or placebo. Prior to randomization, pts must have completed preoperative CRT followed by surgery and been diagnosed with residual pathologic disease after being surgically rendered free of disease with negative margins following complete resection. Pts with stage 4 resectable disease, cervical esophageal cancer, or those who have not received concurrent CRT prior to surgery are not eligible for study enrollment. Primary endpoints are OS and disease-free survival. Other key endpoints include the OS rate at 1, 2, and 3 years and safety. Clinical trial information: NCT02743494.

CheckMate 649: A randomized, multicenter, open-label, phase 3 study of nivolumab (nivo) + ipilimumab (ipi) or nivo + chemotherapy (CTX) vs CTX alone in pts with previously untreated advanced (adv) gastric (G) or gastroesophageal junction (GEJ) cancer

TPS4132

Background: Pts with adv G/GEJ cancer have an OS of ≈ 1 y, indicating an unmet medical need for new first-line treatments (Tx). Expression of the PD-1 ligands PD-L1/PD-L2 is observed in up to 40% of pts with G/GEJ cancer and is associated with poor prognosis. In a phase 3 study of the PD-1 inhibitor nivo vs placebo in pts with adv CTX-refractory (CTX-R; ≥ 2 lines) G/GEJ cancer, nivo reduced the risk of death by 37% (HR, 0.63; P < 0.0001) and increased the OS rate at 12 mo (27% vs 11%; Kang YK, et al. J Clin Oncol. 2017;35 (suppl 4S) [abstract 2]). In a phase 1/2 study in pts with CTX-R G/GEJ/esophageal cancer (79% ≥ 2 prior Tx lines), nivo 1 mg/kg + ipi 3 mg/kg had a manageable safety profile and resulted in 26% ORR (44% ORR in pts with PD-L1+ tumors), a median OS of 6.9 mo, and a 34% OS rate at 12 mo (Janjigian Y, et al. ASCO, 2016 [abstract 4010]). In the phase 1 CheckMate 012 trial, nivo + CTX had clinical activity and manageable safety in pts with NSCLC (Rizvi NA, et al. J Clin Oncol. 2016;34:2969-2979). These positive results support investigation of nivo, nivo + ipi, and nivo + CTX in earlier lines of Tx for G/GEJ cancer. The open-label, phase 3 CheckMate 649 trial will evaluate nivo + ipi and nivo + CTX vs CTX alone as first-line Tx for pts with adv G/GEJ cancer (NCT02872116). Methods: 1266 pts aged ≥ 18 y with untreated, inoperable adv/metastatic G/GEJ cancer (histologically confirmed adenocarcinoma) regardless of PD-L1 status will be randomized to receive either nivo + ipi, nivo + CTX (capecitabine/oxaliplatin [XELOX] or fluorouracil/leucovorin/oxaliplatin [FOLFOX]), or investigator choice of XELOX or FOLFOX. Tumor tissue for determination of PD-L1 status (Dako assay) must be provided from ≤ 6 mo before study Tx. No prior systemic Tx, including HER2 inhibitors, are allowed. Pts with known HER2+ status, suspected autoimmune disease, grade > 1 peripheral neuropathy, or active infection are excluded. Primary endpoint is OS in pts with PD-L1+ (≥ 1%) tumors. Other endpoints include OS in all pts; PFS and time to symptom deterioration in all pts and in pts with PD-L1+ tumors; and safety. Clinical trial information: NCT02872116.

Is proliferative index (Ki-67) useful to stratify patients (pts) with G2 gastroenteropancreatic neuroendocrine tumors (GEP-NETs)? Clinicopathologic correlation

255

Background: Grade 2 (G2) Neuroendocrine tumors (NETs), of the digestive tract is a heterogeneous group of tumors. Several treatment options including chemotherapy and target therapy are available, but there is a lack of prospective trials assessing the role of pronostic factors in this population. Aim(s): to analyze prognostic factors and clinical characteristics in a population of patients with G2 GEP-NETs. To determine the role of ki 67 in the stratification of G2 population. Methods: Study population was obtained from our prospective database (Argentum Group). Survival was estimated using the Kaplan-Meier method and compared between Ki-67 quartiles using the log-rank test. Value of Ki-67 to discriminate mortality was assesed with a ROC curve analysis Results: 144 pts were evaluated. Mean age 54.9, 46.7% male. 102 (70.8%) with metastatic disease, mainly hepatic in 97 pts. (67.4%). 67.9 % underwent surgery. 34% received chemotherapy, and 10.9% target therapy. Median Ki-67 value was 6 (IQR 4-10), ROC curve=0.62 (95% CI 0.53 a 0.72 p=0.021. cut-off: 6.5 (sensitivity 62.2%, specificity 57.7%). Median survival was 97, 67, 51 and 27 months according stratification by quartile (p.001), 45 events (31.7%). Conclusions: Our results suggest that in the heterogenous G2 GEP-NETs there are significant differences in survival. This study was underpowered to detect differences between Ki-67 quartiles, we detected that chemotherapy was mostly used in the higher quartiles.

Somatostatin receptor (SSTR) expression and proliferative index (Ki 67) in 100 patients (pts) with gastroenteropancreatic neuroendocrine tumors (GEP-NETs): Clinical-pathological correlation

e14598

Background: Somatostatin receptor expression (SSTR), mainly subtypes 2 and 5, is a feature of well differentiated GEP-NETs. Such expression has a prognostic and predictive value for the use of somatostatin analogs.Ki 67, present during the cycle phases (G1, S, G2 y M) is a nuclear antigen associated with cell proliferation. The correlation between both clinical and pathological factors is under active investigation in patients with GEP-NETs. Methods: An analysis including 100 patients in the database of the Argentum Group was performed. Consecutive patients were included during the 2006-2007 period. In all cases, a centralized revision of the sample was conducted for diagnosis confirmation.The study of SSTR receptors in tissue and Ki67 was conducted using IHQ.The Kaplan-Meier method was used to analyse survival. Log-rank test was used for the comparative analysis of the variables of interest. Results: The expression of at least one of the SSTRs 2 (a) or 5 was found in 86% and 62% of cases respectivevly in this population. The univariate analysis showed significant differences in the expression of SSTR2 (a) but not in the expression of SSTR 5.The expression of the proliferative index (Ki 67) was associated with significant differences in relation to OS at 5 years, 84% (Ki 67 under or equal to 2%), 66% (Ki 67 between 3 and 15%) and 13% (Ki 67 over 15%). The OS at 5 years in patients with SSTR 2/5 positive and Ki 67 under 2% was 86%, 64% in pts. with SSTR 2/5 positive and Ki 67 over 2% and 20 % in pts. with SSTR 2/5 negative, independent Ki 67 (p .0023). Conclusions: The expression of at least one of the SSTRs 2 (a) or 5 was found in 86% and 62% of cases respectivevly in this population. In the population with GEP-NETs under study, a subgroup of patients with a better prognosis was identified in association with the expression of SSTR 2/5 and Ki67 below 2%. The assessment of SSTR 2(a) and 5 in tissues, together with the study of the proliferative index are a useful tool for prognosis assessment in these patients.