Immune checkpoint blockers in solid organ transplant recipients and cancer: the INNOVATED cohort

BACKGROUND

Patients with solid organ transplant (SOT) and solid tumors are usually excluded from clinical trials testing immune checkpoint blockers (ICB). As transplant rates are increasing, we aimed to evaluate ICB outcomes in this population, with a special focus on lung cancer.

METHODS

We conducted a multicenter retrospective cohort study collecting real data of ICB use in patients with SOT and solid tumors. Clinical data and treatment outcomes were assessed by using retrospective medical chart reviews in every participating center. Study endpoints were: overall response rate (ORR), 6-month progression-free survival (PFS), and grade ≥3 immune-related adverse events.

RESULTS

From August 2016 to October 2022, 31 patients with SOT (98% kidney) and solid tumors were identified (36.0% lung cancer, 19.4% melanoma, 13.0% genitourinary cancer, 6.5% gastrointestinal cancer). Programmed death-ligand 1 expression was positive in 29% of tumors. Median age was 61 years, 69% were males, and 71% received ICB as first-line treatment. In the whole cohort the ORR was 45.2%, with a 6-month PFS of 56.8%. In the lung cancer cohort, the ORR was 45.5%, with a 6-month PFS of 32.7%, and median overall survival of 4.6 months. The grade 3 immune-related adverse events rate leading to ICB discontinuation was 12.9%. Allograft rejection rate was 25.8%, and risk of rejection was similar regardless of the type of ICB strategy (monotherapy or combination, 28% versus 33%, P = 1.0) or response to ICB treatment.

CONCLUSIONS

ICB could be considered a feasible option for SOT recipients with some advanced solid malignancies and no alternative therapeutic options. Due to the risk of allograft rejection, multidisciplinary teams should be involved before ICB therapy.

Patterns of progression on first line osimertinib in patients with EGFR mutation-positive advanced non-small cell lung cancer (NSCLC): A Swiss cohort study

AIM

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) approved for patients with EGFR mutated non-small cell lung cancer as first-line treatment. However, treatment resistance inevitably emerges and may present as oligo-progressive disease (OPD) or systemic progressive disease (SPD). The incidence of OPD on first-line osimertinib is unknown.

METHODS

We retrospectively analyzed patients who received first-line osimertinib at 13 Swiss centers. The rate of OPD (PD in ≤ 5 lesions) and treatment outcomes were analyzed.

RESULTS

The median age of the 148 patients was 68.2 years (range. 38.0-93.3). There were 62 % females, 83 % with a PS ≤ 1, 59 % never smokers, 57 % of patients with an EGFR exon 19 deletion and 37 % with EGFR p.L858R exon 21. 77 % experienced OPD. Median overall survival (OS) was 51.6 months (95 % CI, 38.4-65.0). Median progression-free survival (PFS) was 19.2 (95 % CI, 14.3-23.5) and 8.7 (95 % CI, 2.8-15.6) months for patients with common and uncommon EGFR mutations. Patients with OPD compared to SPD had a significantly longer time to treatment failure and longer OS of (22.9 vs. 10.8 months, p < 0.001 and 51.6 vs. 26.4 months, p = 0.004, respectively). The most common organ sites of PD were lung (62 %), brain (30 %), lymph nodes (30 %), bone (27 %) and pleura (27 %). Twenty-six patients (45 %) with OPD received local ablative treatment (LAT). The OS of OPD patients with LAT was 60.0 (95 % CI, 51.6-NA) vs. 51.4 (95 % CI 38.4-65.3) months (p = 0.43) without LAT.

CONCLUSION

The rate of OPD of patients receiving first line osimertinib was 77 %. Patients with OPD had a significantly better OS compared to patients with SPD (51.6 vs. 26.4 months). Patients with OPD receiving LAT had the longest median OS (60.0 months).

Cost Effectiveness and Budget Impact of Nivolumab Plus Ipilimumab Versus Platinum Plus Pemetrexed (with and Without Bevacizumab) in Patients with Unresectable Malignant Pleural Mesothelioma in Switzerland

BACKGROUND

Malignant pleural mesotheliomas (MPMs) are aggressive and often unresectable. In the past, chemotherapy was the standard for palliative treatment. However, immunotherapy with nivolumab+ipilimumab has recently received marketing approval.

OBJECTIVES

This study evaluated the cost effectiveness of nivolumab+ipilimumab versus pemetrexed+platinum (with/without bevacizumab) for Swiss patients with unresectable MPM, overall and by histological subtype.

METHODS

We developed a three-state Markov cohort model with a cycle length of 1 month, a 30-year time horizon, and a discount rate of 3% per year for costs and benefits. The model included the updated survival and treatment-dependent utility results from the Checkmate-743 and MAPS registration trials. A Swiss statutory health insurance perspective was considered with unit costs for 2022 from publicly available and real-world sources. We assumed a willingness-to-pay (WTP) threshold of CHF100,000/QALY. Model robustness was explored in sensitivity and scenario analyses.

RESULTS

Compared with chemotherapy, nivolumab+ipilimumab incurred additional costs of CHF109,115 and 0.57 additional quality-adjusted life-years (QALYs), yielding an incremental cost-effectiveness ratio (ICER) of CHF192,585/QALY (i.e. USD201,829/QALY) gained. Relative to their 2022 list price, nivolumab+ipilimumab may be cost effective if priced at 48% across all histologies. Assuming cisplatin-based instead of carboplatin-based chemotherapy reduced the ICER to CHF158,911/QALY (i.e. USD166,539/QALY). For the non-epithelioid subtype, nivolumab+ipilimumab was cost effective compared with chemotherapy (ICER of CHF97,894/QALY, i.e. USD102,593/QALY). Chemotherapy+bevacizumab was often a dominated strategy or would require a bevacizumab cost reduction to 28%.

CONCLUSIONS

Our model projected nivolumab+ipilimumab to be cost effective for the non-epithelioid subtype but not for all histologies. Substantial discounts for nivolumab+ipilimumab would be necessary to achieve cost effectiveness for all histologies.

Somatic rearrangements causing oncogenic ectodomain deletions of FGFR1 in squamous cell lung cancer

The discovery of frequent 8p11-p12 amplifications in squamous cell lung cancer (SQLC) has fueled hopes that FGFR1, located inside this amplicon, might be a therapeutic target. In a clinical trial, only 11% of patients with 8p11 amplification (detected by FISH) responded to FGFR kinase inhibitor treatment. To understand the mechanism of FGFR1 dependency, we performed deep genomic characterization of 52 SQLCs with 8p11-p12 amplification, including 10 tumors obtained from patients who had been treated with FGFR inhibitors. We discovered somatically altered variants of FGFR1 with deletion of exons 1-8 that resulted from intragenic tail-to-tail rearrangements. These ectodomain-deficient FGFR1 variants (ΔEC-FGFR1) were expressed in the affected tumors and were tumorigenic in both in vitro and in vivo models of lung cancer. Mechanistically, breakage-fusion-bridges were the source of 8p11-p12 amplification, resulting from frequent head-to-head and tail-to-tail rearrangements. Generally, tail-to-tail rearrangements within or in close proximity upstream of FGFR1 were associated with FGFR1 dependency. Thus, the genomic events shaping the architecture of the 8p11-p12 amplicon provide a mechanistic explanation for the emergence of FGFR1-driven SQLC. Specifically, we believe that FGFR1 ectodomain-deficient and FGFR1-centered amplifications caused by tail-to-tail rearrangements are a novel somatic genomic event that might be predictive of therapeutically relevant FGFR1 dependency.

Early Clearance of Plasma Epidermal Growth Factor Receptor Mutations as a Predictor of Outcome on Osimertinib in Advanced Non-Small Cell Lung Cancer; Exploratory Analysis from AURA3 and FLAURA

PURPOSE

Plasma circulating tumor DNA (ctDNA) analysis is used for genotyping advanced non-small cell lung cancer (NSCLC); monitoring dynamic ctDNA changes may be used to predict outcomes.

PATIENTS AND METHODS

This was a retrospective, exploratory analysis of two phase III trials [AURA3 (NCT02151981), FLAURA (NCT02296125)]. All patients had EGFR mutation-positive (EGFRm; ex19del or L858R) advanced NSCLC; AURA3 also included T790M-positive NSCLC. Osimertinib (FLAURA, AURA3), or comparator EGFR-tyrosine kinase inhibitor (EGFR-TKI; gefitinib/erlotinib; FLAURA), or platinum-based doublet chemotherapy (AURA3) was given. Plasma EGFRm was analyzed at baseline and Weeks 3/6 by droplet digital PCR. Outcomes were assessed by detectable/non-detectable baseline plasma EGFRm and plasma EGFRm clearance (non-detection) at Weeks 3/6.

RESULTS

In AURA3 (n = 291), non-detectable versus detectable baseline plasma EGFRm had longer median progression-free survival [mPFS; HR, 0.48; 95% confidence interval (CI), 0.33-0.68; P < 0.0001]. In patients with Week 3 clearance versus non-clearance (n = 184), respectively, mPFS (months; 95% CI) was 10.9 (8.3-12.6) versus 5.7 (4.1-9.7) with osimertinib and 6.2 (4.0-9.7) versus 4.2 (4.0-5.1) with platinum-pemetrexed. In FLAURA (n = 499), mPFS was longer with non-detectable versus detectable baseline plasma EGFRm (HR, 0.54; 95% CI, 0.41-0.70; P < 0.0001). For Week 3 clearance versus non-clearance (n = 334), respectively, mPFS was 19.8 (15.1 to not calculable) versus 11.3 (9.5-16.5) with osimertinib and 10.8 (9.7-11.1) versus 7.0 (5.6-8.3) with comparator EGFR-TKI. Similar outcomes were observed by Week 6 clearance/non-clearance.

CONCLUSIONS

Plasma EGFRm analysis as early as 3 weeks on-treatment has the potential to predict outcomes in EGFRm advanced NSCLC.

Overall survival and role of programmed death ligand 1 expression in patients with metastatic non-small-cell lung cancer and immunotherapy: an observational study from central Switzerland

BACKGROUND

In clinical trials, therapy with immune checkpoint inhibitors has improved the survival of patients with metastatic non-small-cell lung cancer (NSCLC). These trials were important for drug approval and for defining new treatment standards but the effect of checkpoint inhibitors in patients treated outside of clinical trials is not well known. The goal of this study was to assess the effect of immunotherapy on the overall survival of patients with metastatic NSCLC in the region of central Switzerland.

MATERIALS AND METHODS

The study included 274 patients with histologically confirmed metastatic (stage IV) NSCLC in central Switzerland in the years 2015 to 2018. Patients with NSCLC and actionable driver mutations were excluded. Patients with checkpoint inhibitor treatment (immuno-oncology [IO] group, n = 122) were compared with patients without checkpoint inhibitor treatment (no-IO group, n = 152). Baseline demographics, disease characteristics and therapies applied were collected retrospectively. The primary endpoint was median overall survival calculated either from diagnosis or from the start of checkpoint inhibitor therapy to death or data cut-off (21 July 2021). We used the Kaplan-Meier method and an adjusted Cox proportional-hazards regression model. The expression of programmed-death ligand 1 (PD-L1) on tumour cells was used for exploratory analysis.

RESULTS

Patients had a median age of 68.4 years, most were male (61.7%) and more than half were current or former smokers (65%). A test for PD-L1 expression was available for 55.8% of the tumours. Patients in the IO group were younger than patients in the no-IO group. Among the 122 patients in the IO group, the median overall survival was 15 months (95% confidence interval [CI] 12-20). In the no-IO group, the median overall survival was 4 months (95% CI 3-7) with chemotherapy and 2 months (95% CI 1-2) with best supportive care. Patients with high (≥50%) PD-L1 expression and checkpoint inhibitor therapy had a slightly longer overall survival than patients with low PD-L1 and checkpoint inhibitor therapy.

CONCLUSION

These results suggest that treatment with checkpoint inhibitors improves overall survival in patients with metastatic NSCLC and that PD-L1 expression could have a predictive value in patients treated outside of clinical trials. Further studies are needed to study the magnitude of the benefit of checkpoint inhibitors according to molecular NSCLC subtype.

Selpercatinib in Patients With RET Fusion-Positive Non-Small-Cell Lung Cancer: Updated Safety and Efficacy From the Registrational LIBRETTO-001 Phase I/II Trial

PURPOSE

Selpercatinib, a first-in-class, highly selective, and potent CNS-active RET kinase inhibitor, is currently approved for the treatment of patients with RET fusion-positive non-small-cell lung cancer (NSCLC). We provide a registrational data set update in more than double (n = 316) of the original reported population (n = 144) and better characterization of long-term efficacy and safety.

METHODS

Patients were enrolled to LIBRETTO-001, a phase I/II, single-arm, open-label study of selpercatinib in patients with RET-altered cancers. An analysis of patients with RET fusion-positive NSCLC, including 69 treatment-naive and 247 with prior platinum-based chemotherapy, was performed. The primary end point was objective response rate (ORR; RECIST v1.1, independent review committee). Secondary end points included duration of response (DoR), progression-free survival (PFS), overall survival, and safety.

RESULTS

In treatment-naive patients, the ORR was 84% (95% CI, 73 to 92); 6% achieved complete responses (CRs). The median DoR was 20.2 months (95% CI, 13.0 to could not be evaluated); 40% of responses were ongoing at the data cutoff (median follow-up of 20.3 months). The median PFS was 22.0 months; 35% of patients were alive and progression-free at the data cutoff (median follow-up of 21.9 months). In platinum-based chemotherapy pretreated patients, the ORR was 61% (95% CI, 55 to 67); 7% achieved CRs. The median DoR was 28.6 months (95% CI, 20.4 to could not be evaluated); 49% of responses were ongoing (median follow-up of 21.2 months). The median PFS was 24.9 months; 38% of patients were alive and progression-free (median follow-up of 24.7 months). Of 26 patients with measurable baseline CNS metastasis by the independent review committee, the intracranial ORR was 85% (95% CI, 65 to 96); 27% were CRs. In the full safety population (n = 796), the median treatment duration was 36.1 months. The safety profile of selpercatinib was consistent with previous reports.

CONCLUSION

In a large cohort with extended follow-up, selpercatinib continued to demonstrate durable and robust responses, including intracranial activity, in previously treated and treatment-naive patients with RET fusion-positive NSCLC.

PD-1/PD-L1 inhibitor activity in patients with gene-rearrangement positive non-small cell lung cancer-an IMMUNOTARGET case series

Background

Prior IMMUNOTARGET registry data had suggested that responses to immune [anti PD(L)1] monotherapy in gene-arranged non-small cell lung cancer (NSCLC) were rare or absent, depending on the specific oncogene.

Methods

IMMUNOTARGET sites reporting prior registry data or new individual cases of gene rearranged NSCLC seeming to benefit from immune monotherapy were explored in detail looking to both validate their diagnosis of a functional gene rearrangement and to look for features potentially differentiating them from other such cases associated with low response rates.

Results

Five cases of NSCLC with a gene rearrangement with reported responses or prolonged stabilization from immune monotherapy were identified in total. All had little or no prior smoking history and had programmed death-ligand 1 (PD-L1) values ranging from zero to 100%. A confirmed rearrangement partner was reported in only 2 of the cases (CD74-ROS1 and KIF5B-RET), however in one of the other three cases [analplastic lymophoma kinase (ALK)], significant benefit from a relevant prior targeted therapy was noted, also consistent with the rearrangement status being correctly assigned.

Conclusions

Not all driver oncogene subtypes of NSCLC are equally responsive to immune monotherapy, however even among patients with well-validated gene rearranged NSCLC which has traditionally been considered immune hyporesponsive, objective responses can occur. Additional explorations of the features associated with and underlying the immune hypo-responsiveness of most, but not all, cases of gene-rearranged NSCLC are required.

Clinical Activity of Mitogen-Activated Protein Kinase-Targeted Therapies in Patients With Non-V600 BRAF-Mutant Tumors

PURPOSE

Non-V600 mutations comprise approximately 35% of all BRAF mutations in cancer. Many of these mutations have been identified as oncogenic drivers and can be classified into three classes according to molecular characteristics. Consensus treatment strategies for class 2 and 3 BRAF mutations have not yet been established.

METHODS

We performed a systematic review and meta-analysis with published reports of individual patients with cancer harboring class 2 or 3 BRAF mutations from 2010 to 2021, to assess treatment outcomes with US Food and Drug Administration-approved mitogen-activated protein kinase (MAPK) pathway targeted therapy (MAPK TT) according to BRAF class, cancer type, and MAPK TT type. Coprimary outcomes were response rate and progression-free survival.

RESULTS

A total of 18,167 studies were screened, identifying 80 studies with 238 patients who met inclusion criteria. This included 167 patients with class 2 and 71 patients with class 3 BRAF mutations. Overall, 77 patients achieved a treatment response. In both univariate and multivariable analyses, response rate and progression-free survival were higher among patients with class 2 compared with class 3 mutations, findings that remain when analyses are restricted to patients with melanoma or lung primary cancers. MEK ± BRAF inhibitors demonstrated greater clinical activity in class 2 compared with class 3 BRAF-mutant tumors than BRAF or EGFR inhibitors.

CONCLUSION

This meta-analysis suggests that MAPK TTs have clinical activity in some class 2 and 3 BRAF-mutant cancers. BRAF class may dictate responsiveness to current and emerging treatment strategies, particularly in melanoma and lung cancers. Together, this analysis provides clinical validation of predictions made on the basis of a mutation classification system established in the preclinical literature. Further evaluation with prospective clinical trials is needed for this population.

LIBRETTO-001 cohort 7: A single-arm, phase 2 study of neoadjuvant selpercatinib in patients with resectable stage IB-IIIA RET fusion-positive NSCLC

TPS8594

Background: Despite definitive surgery and perioperative chemotherapy, many patients with locoregional non-small cell lung cancer (NSCLC) continue to experience recurrent disease and limited survival. Although targeted therapies are standard treatment for metastatic NSCLC with genomic alterations, their use in the early-stage setting is still being characterized. Initial studies examining targeted therapy in neoadjuvant setting for early-stage epidermal growth factor receptor positive NSCLC has shown promise. Selpercatinib is a highly selective, potent, and central nervous system active rearranged during transfection (RET) inhibitor with demonstrated robust and sustained antitumor activity and manageable toxicity in patients with RET fusion-positive advanced NSCLC. Cohort 7 of the Phase 2, open-label, single arm LIBRETTO-001 study evaluates efficacy and safety of neoadjuvant selpercatinib in patients with resectable stage IB-IIIA RET fusion-positive NSCLC (NCT03157128). Methods: Key eligibility criteria include age ≥18 years; histologically confirmed stage IB–IIIA NSCLC (AJCC, version 8); presence of RET fusion in tumor (by PCR or NGS) or blood (by NGS) (pre-treatment biopsy confirmed); resectable and operable tumor; measurable disease (RECIST 1.1); and ECOG performance status 0-1. Key exclusion criteria include presence of other known oncogenic drivers; and concurrent investigational anticancer therapy. Eligible patients will undergo full staging including radiographic tumor measurements using CT, PET, and brain MRI at baseline and after two 28-day cycles of neoadjuvant selpercatinib, followed by surgery. Dosing regimen is 160 mg twice daily. Resected tumor specimens will be sent to an Independent Pathology Review Committee (IPRC) for evaluation. Patients may then be treated with stage-appropriate adjuvant therapy/surveillance, based on the treating physician’s decision, followed by selpercatinib until disease recurrence, unacceptable toxicity, withdrawal, or death, for a maximum treatment duration of 3 years. The primary endpoint is to determine the rate of major pathologic response (MPR) by IPRC, defined as ≤ 10% residual viable tumor cells in the surgically resected specimen. Efficacy based on the MPR will be assessed using the Simon's 2-stage design. In Stage I, 9 patients will be enrolled; if ≤1 patient achieves an MPR, the study will be stopped. Otherwise, at least 10 additional patients will be enrolled, with a total of 19 patients undergoing surgery. The rate of pathologic complete response (pCR) by IPRC, disease-free survival, and overall survival will be assessed as secondary endpoints. pCR rate will be determined at the time of surgery, indicating no remaining viable tumor cells. Safety of peri-operative treatment will be assessed, including 30- and 90-day post-operative readmission and mortality rates. Clinical trial information: NCT03157128.

Intracranial Activity of Osimertinib Plus Capmatinib in a Patient With EGFR and MET-Driven Lung Cancer: Case Report

We previously published in the Journal of Thoracic Oncology the case of a patient with EGFR and MET-driven lung cancer and extracranial response to capmatinib and osimertinib. Here, we report on a second patient treated with the same combination, revealing complete and durable intracranial response. Adding capmatinib to osimertinib seems to be an effective salvage therapy for patients with EGFR-mutant lung cancer and acquired MET amplification.

Intracranial Efficacy of Selpercatinib in RET Fusion-Positive Non-Small Cell Lung Cancers on the LIBRETTO-001 Trial

PURPOSE

We report the intracranial efficacy of selpercatinib, a highly potent and selective RET inhibitor, approved in the United States for RET fusion-positive non-small cell lung cancers (NSCLC).

PATIENTS AND METHODS

In the global phase 1/2 LIBRETTO-001 trial (NCT03157128) in advanced RET-altered solid tumors, selpercatinib was dosed orally (160 mg twice every day) in 28-day cycles. Patients with baseline intracranial metastases had MRI/CT scans every 8 weeks for 1 year (12 weeks thereafter). In this pre-planned analysis of patients with RET fusion-positive NSCLC with baseline intracranial metastases, the primary endpoint was independently assessed intracranial objective response rate (ORR) per RECIST 1.1. Secondary endpoints included intracranial disease control rate, intracranial duration of response, and intracranial progression-free survival (PFS) independently reviewed.

RESULTS

Eighty patients with NSCLC had brain metastases at baseline. Patients were heavily pretreated (median = 2 systemic therapies, range = 0-10); 56% of patients received ≥1 course of intracranial radiation (14% whole brain radiotherapy, 45% stereotactic radiosurgery). Among 22 patients with measurable intracranial disease at baseline, intracranial ORR was 82% [95% confidence interval (CI), 60-95], including 23% with complete responses. Among all intracranial responders (measurable and nonmeasurable, n = 38), median duration of intracranial response was not reached (95% CI, 9.3-NE) at a median duration of follow-up of 9.5 months (IQR = 5.7, 12.0). At 12 months, 55% of intracranial responses were ongoing. In all 80 patients, median intracranial PFS was 13.7 months (95% CI, 10.9-NE) at a median duration of follow-up of 11.0 months (IQR = 7.4, 16.5). No new safety signals were revealed in patients with brain metastases compared with the full NSCLC trial population.

CONCLUSIONS

Selpercatinib has robust and durable intracranial efficacy in patients with RET fusion-positive NSCLC.

A cost-effectiveness analysis of pembrolizumab with or without chemotherapy for the treatment of patients with metastatic, non-squamous non-small cell lung cancer and high PD-L1 expression in Switzerland

INTRODUCTION

Pembrolizumab monotherapy or in combination with chemotherapy are two new treatment options for patients with metastatic non-squamous non-small cell lung cancer (NSCLC) and high (≥ 50%) programmed death ligand 1 (PD-L1) expression. We conducted a cost-effectiveness analysis for Switzerland comparing these two options but also pembrolizumab to chemotherapy.

METHODS

We constructed a 3-state Markov model with a time horizon of 10 years. Parametric functions were fitted to Kaplan-Meier overall survival (OS) and progression-free survival (PFS) using 2-year follow-up data from the KN-024 and KN-189 registration trials. We included estimated costs for further treatment lines and costs for best supportive care. Costs were assessed from the Swiss healthcare payer perspective. We used published utility values.

RESULTS

Combination therapy resulted in an expected gain of 0.17 quality-adjusted life years (QALYs) per patient and incremental costs of Swiss Francs (CHF) 81,085 as compared to pembrolizumab. These estimates led to an incremental cost-effectiveness ratio (ICER) of CHF 475,299/QALY. Pembrolizumab in comparison to chemotherapy was estimated to generate mean incremental QALYs of 0.83 and incremental costs of CHF 56,585, resulting in an ICER of CHF 68,580/QALY. Results were most sensitive to changes in costs of 1L pembrolizumab and combination therapy, together with changes in PFS. In the probabilistic sensitivity analysis, we estimated combination therapy was cost-effective in 4.9% of the simulations and pembrolizumab monotherapy in 82.9%, assuming a willingness-to-pay threshold of CHF 100,000 per QALY gained.

CONCLUSIONS

Pembrolizumab is likely to be cost-effective from the Swiss healthcare payer perspective, whereas pembrolizumab plus chemotherapy is not.

Abstract CT011: Efficacy and safety of selpercatinib in RET fusion-positive cancers other than lung or thyroid cancers

Introduction: Selpercatinib, a first-in-class highly selective and potent RET kinase inhibitor, is approved in multiple countries for the treatment of RET fusion-positive lung or thyroid cancers. RET fusions are also implicated in the pathogenesis of other cancers. Selpercatinib's efficacy and safety were thus explored in patients (pts) with RET fusion-positive non-lung/non-thyroid cancers in a global, multicenter, registrational trial. Methods: Adults with locally advanced or metastatic RET fusion-positive non-lung/non-thyroid solid tumors enrolled in the phase 1/2 LIBRETTO-001 trial (NCT03157128) were included in this analysis (data cut-off: 19 March 2021). Following dose escalation, pts received the recommended dose of 160 mg orally, twice daily. Pts enrolled long enough to allow 6-month follow-up from their first dose comprised the efficacy-evaluable population. Response was assessed (RECIST 1.1) by investigators. The primary endpoint was objective response rate (ORR). Secondary endpoints included duration of response (DoR), time to response, and safety. Results: Thirty-two pts with RET fusion-positive non-lung/non-thyroid cancers included 12 unique tumor types: 9 pancreatic, 9 colon, 2 each of breast, salivary, sarcoma, and unknown primary, and 1 each of carcinoid, rectal neuroendocrine, small intestine, xanthogranuloma, ovarian, and pulmonary carcinosarcoma. The median age was 48 years (range 22-85). Twenty-nine pts received prior systemic therapy (median prior lines: 2, range 0-9). The ORR was 47% (N=15/32, 95% CI: 29-65). Objective responses were observed in 9 unique cancer types including colon, pancreatic, carcinoid, small intestine, salivary, xanthogranuloma, breast, ovarian, and sarcoma, and 5 additional patients had stable disease lasting ≥ 16 weeks. Median time to response was 1.9 months (range 0.7-7.3). Median DoR was not reached (median follow-up time of 13 months). Responses were ongoing in 73% (11/15) of pts. Safety among this population was consistent with the overall selpercatinib safety database. No patients in this cohort discontinued due to treatment-related AEs. Conclusion: Selpercatinib demonstrated promising antitumor activity in RET fusion-positive non-lung/non-thyroid cancers, including multiple treatment-refractory GI malignancies. Broad-based genomic profiling is essential to identify actionable oncogenic drivers, including RET fusions. The safety and efficacy of selpercatinib will continue to be explored in pts with these cancers in the ongoing LIBRETTO-001 study.

Citation Format: Vivek Subbiah, Bhavana Konda, Todd Bauer, Caroline McCoach, Gerald Falchook, Masayuki Takeda, Jyoti Patel, Jared Weiss, Nir Peled, Lyudmila Bazhenova, Victoria Soldatenkova, Pearl French, Nora Drove, Oliver Gautschi, Alexander Drilon. Efficacy and safety of selpercatinib in RET fusion-positive cancers other than lung or thyroid cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT011.

Response to selpercatinib versus prior systemic therapy in patients (pts) with RET fusion+ non-small-cell lung cancer (NSCLC)

9032

Background: Selpercatinib, a first-in-class highly selective, potent, CNS-active RET kinase inhibitor, is approved in multiple countries for treatment of RET fusion+ lung or thyroid cancers. Selpercatinib demonstrated durable antitumor activity in previously treated pts with RET fusion+ NSCLC in an ongoing Phase 1/2 trial, LIBRETTO-001 (Besse et al., ASCO 2021). Methods: Pts with RET fusion+ NSCLC enrolled in the global, multicenter, LIBRETTO-001 trial (NCT03157128; 16 countries, 89 sites). Primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival, duration of response, and safety. This post-hoc intrapatient analysis was based on a 30 March 2020 data cutoff date. Historical physician-reported best overall response (BOR) from last systemic therapy received prior to enrollment was compared with selpercatinib BOR by independent review committee per RECIST v1.1, with each patient serving as his/her own control. Results: In efficacy-evaluable pts (N = 218) who previously received platinum-based chemotherapy (chemo), median pt age was 61 years, the majority with ECOG of 0/1 (37%/61%), with a median of 2 (range: 1-15) prior systemic therapies. Overall, 57% of patients responded to selpercatinib while 16% responded to the immediate prior therapy. ORR improvements with selpercatinib were observed regardless of prior therapy: chemotherapy + immune checkpoint inhibitor (ICI) (57% vs 14%), single-agent ICI (48% vs 3%), or chemotherapy (58% vs 15%). A total of 108 patients (49%) did not respond to immediate prior therapy but responded to selpercatinib. Fewer patients had progressive disease as their BOR with selpercatinib (2%) compared to the immediate prior therapy (28%). The median duration of therapy for selpercatinib was notably extended compared with that of the immediate prior therapy (11.8 vs. 3.4 months, respectively). Conclusions: In pts with RET fusion+ NSCLC treated on LIBRETTO-001, systemic therapies administered prior to enrollment achieved less meaningful clinical benefit than selpercatinib. Selpercatinib demonstrated consistent efficacy regardless of the type of prior therapy. Clinical trial information: NCT03157128.

Updated overall efficacy and safety of selpercatinib in patients (pts) with RET fusion+ non-small cell lung cancer (NSCLC)

9065

Background: Selpercatinib, a first-in-class highly selective and potent, CNS-active RET kinase inhibitor, is approved in multiple countries for treatment of RET fusion+ lung or thyroid cancers. Here we report an update of efficacy and safety results which provide a longer follow up and increased number of patients (safety population: N = 345 vs N = 329). Methods: Pts with RET fusion+ NSCLC enrolled in the global, multicenter, ongoing LIBRETTO-001 trial (NCT03157128; 16 countries, 89 sites) were included in this analysis. Pts with the opportunity to be followed ≥6 months from their first dose were included in the efficacy-evaluable population for these analyses. Integrated analysis set (IAS) included 218 NSCLC pts with prior platinum-chemotherapy. Primary analysis set (PAS) was a subset of the IAS and included the first 105 consecutively enrolled pts. The treatment-naïve population included 48 efficacy-evaluable pts. Primary endpoint was objective response rate (ORR, RECIST v1.1) by independent review committee (IRC). Secondary endpoints included ORR by investigator, duration of response (DoR), progression-free survival (PFS), clinical benefit rate (CBR; CR+PR+SD ≥16 weeks), and safety. Safety population (N = 345) included all pts with NSCLC who received ≥1 selpercatinib dose by data cutoff (30 Mar 2020). Results: In pts with prior treatment (N = 218) and treatment-naïve (N = 48) pts, 56% and 60% were female, with a median pt age of 61 and 64 years, respectively. The ORR with selpercatinib was 57% in the IAS, 64% in the PAS, and 85% in the treatment-naïve population (Table). In both the IAS and PAS, the median DoR was 17.5 months, median PFS was 19.3 months at median follow-up of 12.0 and 15.7 months, respectively (Table). The most common treatment-emergent adverse events (TEAEs) reported in ≥25% of pts were dry mouth, diarrhea, hypertension, increased ALT/AST, edema peripheral, and fatigue. Twenty-five pts (7%) permanently discontinued due to TEAEs, with 10 pts (3%) discontinuing selpercatinib due to treatment-related AEs as per investigator. Conclusions: In this updated data set, selpercatinib continued to demonstrate durable antitumor activity in pts with RET-fusion+ NSCLC. Selpercatinib was well-tolerated with a safety profile consistent with previous reports. A global, randomized, phase 3 trial (LIBRETTO-431) evaluating selpercatinib compared with standard frontline therapy is ongoing. Clinical trial information: NCT03157128. [Table: see text]

Binimetinib, pemetrexed and cisplatin, followed by maintenance of binimetinib and pemetrexed in patients with advanced non-small cell lung cancer (NSCLC) and KRAS mutations. The phase 1B SAKK 19/16 trial

BACKGROUND

KRAS mutations are found in 20-25 % of non-squamous non-small cell lung cancer (NSCLC) and therapies targeting the RAS/MEK/ERK pathway are in development. We performed a multicenter open-label phase 1B trial to determine the recommended phase 2 dose and early antitumor activity of the MEK-inhibitor binimetinib combined with cisplatin and pemetrexed.

METHODS

Eligible patients (pts) had stage III-IV NSCLC unsuitable for curative treatment, KRAS exon 2 or 3 (codon 12, 13 or 61) mutations, no prior systemic therapy. Pts were enrolled into part 1: 3 + 3 design with dose escalation in 2 dose levels (DL) of binimetinib and part 2: expansion cohort at the maximum tolerated dose (MTD). Pts received 4 cycles of cisplatin 75 mg/m², pemetrexed 500 mg/m²and binimetinib 30 (DL1)/45 mg (DL2) orally twice a day (bid) d1-14 q3w followed by pemetrexed and binimetinib until progressive disease (PD) or unacceptable toxicity.

RESULTS

From May 2017 to Dec 2019, 18 pts (13 dose escalation, 5 expansion cohort) were enrolled. Median age was 60 (48-73, range). KRAS mutations were 87.5 % at codon 12. No DLT occurred in the dose escalation cohort. Median number of cycles was 2 (1-17, range). Treatment discontinuation was mainly due to PD (33 %) or pts/physicians' decision (27 %). Together with the expansion cohort, 16 pts were evaluable for safety. Most frequent treatment-related grade 3 AEs were lung infection (25 %), fatigue (19 %), anemia (19 %). Overall response rate among 9 evaluable pts receiving binimetinib at MTD (45 mg bid) was 33 % (7-70 %, 95 % CI). Median progression-free survival was 5.7 months (1.1-14.0, 95 % CI) and overall survival 6.5 months (1.8-NR, 95 % CI).

CONCLUSIONS

Pts treated with combination of cisplatin, pemetrexed and binimetinib presented no unexpected toxicity. No early signal of increased antitumor activity of binimetinib added to chemotherapy was observed in our pts population.

Advances in the treatment of RET-fusion-positive lung cancer

Ten years ago, RET-fusions were discovered as oncogenic drivers and potential drug targets in approximately 1% of metastatic lung adenocarcinomas. Several multikinase inhibitors were tested in clinical trials, however, their antitumor activity was limited. Recently, two selective and potent RET-inhibitors were approved for the treatment of patients with metastatic RET-fusion-positive lung cancer (RET-NSCLC). Here, we discuss the two RET-inhibitors selpercatinib and pralsetinib, and the management of patients with RET-fusion positive NSCLC.

A multicentre randomised phase III trial comparing pembrolizumab versus single-agent chemotherapy for advanced pre-treated malignant pleural mesothelioma: the European Thoracic Oncology Platform (ETOP 9-15) PROMISE-meso trial

BACKGROUND

Malignant pleural mesothelioma (MPM) is an aggressive malignancy characterised by limited treatment options and a poor prognosis. At relapse after platinum-based chemotherapy, single-agent chemotherapy is commonly used and single-arm trials of immune-checkpoint inhibitors have demonstrated encouraging activity.

PATIENTS AND METHODS

PROMISE-meso is an open-label 1:1 randomised phase III trial investigating the efficacy of pembrolizumab (200 mg/Q3W) versus institutional choice single-agent chemotherapy (gemcitabine or vinorelbine) in relapsed MPM patients with progression after/on previous platinum-based chemotherapy. Patients were performance status 0-1 and unselected for programmed cell death ligand 1 (PD-L1) status. At progression, patients randomly assigned to receive chemotherapy were allowed to crossover to pembrolizumab. The primary end point was progression-free survival (PFS), assessed by blinded independent central review (BICR). Secondary end points were overall survival (OS), investigator-assessed PFS, objective response rate (ORR), and safety. Efficacy by PD-L1 status was investigated in exploratory analyses.

RESULTS

Between September 2017 and August 2018, 144 patients were randomly allocated (pembrolizumab: 73; chemotherapy: 71). At data cut-off [20 February 2019, median follow-up of 11.8 months (interquartile range: 9.9-14.5)], 118 BICR-PFS events were observed. No difference in BICR-PFS was detected [hazard ratio = 1.06, 95% confidence interval (CI): 0.73-1.53; P = 0.76], and median BICR-PFS (95% CI) for pembrolizumab was 2.5 (2.1-4.2), compared with 3.4 (2.2-4.3) months for chemotherapy. A difference in ORR for pembrolizumab was identified (22%, 95% CI: 13% to 33%), over chemotherapy (6%, 95% CI: 2% to 14%; P = 0.004). Forty-five patients (63%) assigned to chemotherapy received pembrolizumab at progression. With follow-up to 21 August 2019 [17.5 months: (14.8-19.7)], no difference in OS was detected between groups (HR = 1.12, 95% CI: 0.74-1.69; P = 0.59), even after adjusting for crossover. Pembrolizumab safety was consistent with previous observations. Exploratory efficacy analyses by PD-L1 status demonstrated no improvements in ORR/PFS/OS.

CONCLUSION

This is the first randomised trial evaluating the efficacy of pembrolizumab in MPM patients progressing after/on previous platinum-based chemotherapy. In biologically unselected patients, although associated with an improved ORR, pembrolizumab improves neither PFS nor OS over single-agent chemotherapy.

Efficacy of Selpercatinib in RET Fusion-Positive Non-Small-Cell Lung Cancer

BACKGROUND

RET fusions are oncogenic drivers in 1 to 2% of non-small-cell lung cancers (NSCLCs). In patients with RET fusion-positive NSCLC, the efficacy and safety of selective RET inhibition are unknown.

METHODS

We enrolled patients with advanced RET fusion-positive NSCLC who had previously received platinum-based chemotherapy and those who were previously untreated separately in a phase 1-2 trial of selpercatinib. The primary end point was an objective response (a complete or partial response) as determined by an independent review committee. Secondary end points included the duration of response, progression-free survival, and safety.

RESULTS

In the first 105 consecutively enrolled patients with RET fusion-positive NSCLC who had previously received at least platinum-based chemotherapy, the percentage with an objective response was 64% (95% confidence interval [CI], 54 to 73). The median duration of response was 17.5 months (95% CI, 12.0 to could not be evaluated), and 63% of the responses were ongoing at a median follow-up of 12.1 months. Among 39 previously untreated patients, the percentage with an objective response was 85% (95% CI, 70 to 94), and 90% of the responses were ongoing at 6 months. Among 11 patients with measurable central nervous system metastasis at enrollment, the percentage with an objective intracranial response was 91% (95% CI, 59 to 100). The most common adverse events of grade 3 or higher were hypertension (in 14% of the patients), an increased alanine aminotransferase level (in 12%), an increased aspartate aminotransferase level (in 10%), hyponatremia (in 6%), and lymphopenia (in 6%). A total of 12 of 531 patients (2%) discontinued selpercatinib because of a drug-related adverse event.

CONCLUSIONS

Selpercatinib had durable efficacy, including intracranial activity, with mainly low-grade toxic effects in patients with RET fusion-positive NSCLC who had previously received platinum-based chemotherapy and those who were previously untreated. (Funded by Loxo Oncology and others; LIBRETTO-001 ClinicalTrials.gov number, NCT03157128.).

Efficacy of Selpercatinib in RET-Altered Thyroid Cancers

BACKGROUND

RET mutations occur in 70% of medullary thyroid cancers, and RET fusions occur rarely in other thyroid cancers. In patients with RET-altered thyroid cancers, the efficacy and safety of selective RET inhibition are unknown.

METHODS

We enrolled patients with RET-mutant medullary thyroid cancer with or without previous vandetanib or cabozantinib treatment, as well as those with previously treated RET fusion-positive thyroid cancer, in a phase 1-2 trial of selpercatinib. The primary end point was an objective response (a complete or partial response), as determined by an independent review committee. Secondary end points included the duration of response, progression-free survival, and safety.

RESULTS

In the first 55 consecutively enrolled patients with RET-mutant medullary thyroid cancer who had previously received vandetanib, cabozantinib, or both, the percentage who had a response was 69% (95% confidence interval [CI], 55 to 81), and 1-year progression-free survival was 82% (95% CI, 69 to 90). In 88 patients with RET-mutant medullary thyroid cancer who had not previously received vandetanib or cabozantinib, the percentage who had a response was 73% (95% CI, 62 to 82), and 1-year progression-free survival was 92% (95% CI, 82 to 97). In 19 patients with previously treated RET fusion-positive thyroid cancer, the percentage who had a response was 79% (95% CI, 54 to 94), and 1-year progression-free survival was 64% (95% CI, 37 to 82). The most common adverse events of grade 3 or higher were hypertension (in 21% of the patients), increased alanine aminotransferase level (in 11%), increased aspartate aminotransferase level (in 9%), hyponatremia (in 8%), and diarrhea (in 6%). Of all 531 patients treated, 12 (2%) discontinued selpercatinib owing to drug-related adverse events.

CONCLUSIONS

In this phase 1-2 trial, selpercatinib showed durable efficacy with mainly low-grade toxic effects in patients with medullary thyroid cancer with and without previous vandetanib or cabozantinib treatment. (Funded by Loxo Oncology and others; LIBRETTO-001 ClinicalTrials.gov number, NCT03157128.).

Real-World Treatment Patterns and Survival Outcome in Advanced Anaplastic Lymphoma Kinase (ALK) Rearranged Non-Small-Cell Lung Cancer Patients

Introduction: Survival of ALK-rearranged NSCLC patients has dramatically improved by the use of multiple ALK-tyrosine kinase inhibitors (ALK-TKI). However, still little is known about the impact of drug sequencing and clinical features on survival in a real-world setting.

Methods: Patients with stage IV ALK-rearranged NSCLC treated at six centers in Switzerland and Italy were identified and standard clinical variables collected. OS curves were constructed using the Kaplan–Meier method and compared with the log-rank test. Multivariate Cox proportional hazard analysis was applied to determine the correlations between clinical features and OS. In four patients, biopsies were subjected to NGS.

Results: One-hundred and twenty-one patients with stage IV ALK-rearranged NSCLC diagnosed between 2011 and 2016 were included. With a median follow-up time of 39.5 months, the median OS from diagnosis of stage IV disease was 48.0 months. First-line treatment consisted of an ALK-TKI in 24% of patients, with crizotinib in 83% of them. Chemotherapy as first-line treatment did not influence OS (p = 0.955). The use of more than one ALK-TKI line positively correlated with OS (p = 0.016), as well as the use of alectinib or lorlatinib in any treatment line, as compared to the use of crizotinib ± ceritinib (p = 0.022). A never smoking history was an independent prognostic factor for OS (p = 0.032). Moreover, treatment with alectinib significantly improved OS.

Conclusions: Targeted treatment for ALK-positive NSCLC patients lead to prolonged OS. Smoking status was a negative independent prognostic factor in a multi-variate analysis. The use of alectinib or lorlatinib in any treatment line improved overall outcome.

Chemotherapy negatively impacts the tumor immune microenvironment in NSCLC: an analysis of pre- and post-treatment biopsies in the multi-center SAKK19/09 study

Background

Over the past few years, immune checkpoint inhibitors have changed the therapeutic landscape of non-small-cell lung cancer (NSCLC). Response to immune checkpoint inhibitors correlates with a pre-existing anti-tumoral immune response. Checkpoint inhibitors have been introduced as second-line therapy and are only very recently used as monotherapy or in combination with chemotherapy as first-line treatment of NSCLC. However, the effect of conventional first-line platinum-based chemotherapy on the immune infiltrate in the tumor is largely unknown.

Methods

We measured the gene expression of a custom set of 201 cancer- and immune-related genes in 100 NSCLC tumor biopsies collected before chemotherapy and 33 re-biopsies after platinum-based chemotherapy at the time point of progression. For 29 patients matched pre- and post-chemotherapy samples could be evaluated.

Results

We identified a cluster of 47 co-expressed immune genes, including PDCD1 (PD1) and CD274 (PD-L1), along with three other co-expression clusters. Chemotherapy decreased the average gene expression of the immune cluster while no effect was observed on the other three cluster. Within this immune cluster, CTLA4, LAG3, TNFRSF18, CD80 and FOXP3 were found to be significantly decreased in patient-matched samples after chemotherapy.

Conclusion

Our results suggest that conventional platinum-based chemotherapy negatively impacts the immune microenvironment at the time point of secondary progression.

Electronic supplementary material

The online version of this article (10.1007/s00262-020-02688-4) contains supplementary material, which is available to authorized users.

GLASS: Global Lorlatinib for ALK(+) and ROS1(+) retrospective Study: real world data of 123 NSCLC patients

Lorlatinib is a third-generation tyrosine-kinases inhibitor (TKI) targeting ALK/ROS1 fusions. The FDA has approved lorlatinib for TKI-pretreated ALK(+) NSCLC, while its approval for ROS1(+) is still pending. Here we present the largest real-world data of NSCLC patients harboring ALK/ROS1 rearrangements treated with lorlatinib.

METHODS

123 patients were enrolled retrospectively (data cut-off 1/1/2019). Lorlatinib was administered through an early access program for patients with no other available therapy. Outcome and response were defined by each investigator upon RECIST 1.1 criteria.

RESULTS

106 ALK(+) and 17 ROS1(+) patients recruited from 8 different countries. The ALK(+) cohort included 50 % males, 73 % never-smokers and 68 % with brain metastases. Extracranial (EC) and intracranial (IC) response rates (RR) were 60 % and 62 %, with disease control rates (DCR) of 91 % and 88 % respectively. Mean duration of therapy (DoT) was 23.9 ± 1.6 months and median overall survival (mOS) was 89.1 ± 19.6 months. ROS1 cohort enrolled 53 % males, 65 % never-smokers and 65 % had brain metastases. EC and IC RR were 62 % and 67 % with DCR of 92 % and 78 % respectively. Median DoT was 18.1 ± 2.5 months and mOS of 90.3 ± 24.4 months. OS and DoT in both cohorts were not significantly correlated with line of therapy nor other parameters. The most common adverse events of any grade were peripheral edema (48 %), hyperlipidemia (47 %), weight gain (25 %) and fatigue (30 %). CNS adverse events such as cognitive effect of grade 1-2 were reported in 18 % of patients.

CONCLUSION

Lorlatinib shows outstanding EC/IC efficacy in ALK/ROS1(+) NSCLC. The observed mOS of 89 ± 19 months in ALK(+) NSCLC supports previous reports, while mOS from of 90 ± 24 months is unprecedented for ROS1(+) NSCLC.

A Randomized Open-Label Phase III Trial Evaluating the Addition of Denosumab to Standard First-Line Treatment in Advanced NSCLC: The European Thoracic Oncology Platform (ETOP) and European Organisation for Research and Treatment of Cancer (EORTC) SPLENDOUR Trial

INTRODUCTION

Receptor activator of NF-kB ligand stimulates NF-kB-dependent cell signaling and acts as the primary signal for bone resorption. Retrospective analysis of a large trial comparing denosumab versus zoledronic acid in bone metastatic solid tumors suggested significant overall survival (OS) advantage for patients with lung cancer with denosumab (p = 0.01). The randomized open-label phase III SPLENDOUR trial was designed to evaluate whether the addition of denosumab to standard first-line platinum-based doublet chemotherapy improved OS in advanced NSCLC.

METHODS

Patients with stage IV NSCLC were randomized in a 1:1 ratio to either chemotherapy with or without denosumab (120 mg every 3-4 wks), stratified by the presence of bone metastases (at diagnosis), Eastern Cooperative Oncology Group performance status, histology, and region. To detect an OS increase from 9 to 11.25 months (hazard ratio [HR] = 0.80), 847 OS events were required. The trial closed prematurely owing to decreasing accrual rate.

RESULTS

A total of 514 patients were randomized, with 509 receiving one or more doses of the assigned treatment (chemotherapy: 252, chemotherapy-denosumab: 257). The median age was 66.1 years, 71% were men, and 59% were former smokers. Bone metastases were identified in 275 patients (53%). Median OS (95% confidence interval [CI]) was 8.7 (7.6-11.0) months in the control arm versus 8.2 (7.5-10.4) months in the chemotherapy-denosumab arm (HR = 0.96; 95% CI: 0.78-1.19; one-sided p = 0.36). For patients with bone metastasis, HR was 1.02 (95% CI: 0.77-1.35), whereas for those without, HR was 0.90 (95% CI: 0.66-1.23). Adverse events grade 3 or greater were observed in 40.9%, 5.2%, 8.7% versus 45.5%, 10.9%, 10.5% of patients. Conditional power for OS benefit was less than or equal to 10%.

CONCLUSIONS

Denosumab was well-tolerated without unexpected safety concerns. There was no OS improvement for denosumab when added to chemotherapy in the intention-to-treat population and the subgroups with and without bone metastases. Our data do not provide evidence of a clinical benefit for denosumab in patients with NSCLC without bone metastases.

Immune checkpoint inhibitors for patients with advanced lung cancer and oncogenic driver alterations: results from the IMMUNOTARGET registry

Background

Anti-PD1/PD-L1 directed immune checkpoint inhibitors (ICI) are widely used to treat patients with advanced non-small-cell lung cancer (NSCLC). The activity of ICI across NSCLC harboring oncogenic alterations is poorly characterized. The aim of our study was to address the efficacy of ICI in the context of oncogenic addiction.

Patients and methods

We conducted a retrospective study for patients receiving ICI monotherapy for advanced NSCLC with at least one oncogenic driver alteration. Anonymized data were evaluated for clinicopathologic characteristics and outcomes for ICI therapy: best response (RECIST 1.1), progression-free survival (PFS), and overall survival (OS) from ICI initiation. The primary end point was PFS under ICI. Secondary end points were best response (RECIST 1.1) and OS from ICI initiation.

Results

We studied 551 patients treated in 24 centers from 10 countries. The molecular alterations involved KRAS (n = 271), EGFR (n = 125), BRAF (n = 43), MET (n = 36), HER2 (n = 29), ALK (n = 23), RET (n = 16), ROS1 (n = 7), and multiple drivers (n = 1). Median age was 60 years, gender ratio was 1 : 1, never/former/current smokers were 28%/51%/21%, respectively, and the majority of tumors were adenocarcinoma. The objective response rate by driver alteration was: KRAS = 26%, BRAF = 24%, ROS1 = 17%, MET = 16%, EGFR = 12%, HER2 = 7%, RET = 6%, and ALK = 0%. In the entire cohort, median PFS was 2.8 months, OS 13.3 months, and the best response rate 19%. In a subgroup analysis, median PFS (in months) was 2.1 for EGFR, 3.2 for KRAS, 2.5 for ALK, 3.1 for BRAF, 2.5 for HER2, 2.1 for RET, and 3.4 for MET. In certain subgroups, PFS was positively associated with PD-L1 expression (KRAS, EGFR) and with smoking status (BRAF, HER2).

Conclusions

: ICI induced regression in some tumors with actionable driver alterations, but clinical activity was lower compared with the KRAS group and the lack of response in the ALK group was notable. Patients with actionable tumor alterations should receive targeted therapies and chemotherapy before considering immunotherapy as a single agent.

Selpercatinib (LOXO-292) in patients with RET-mutant medullary thyroid cancer

3594

Background: Selpercatinib (LOXO-292) is a highly selective and potent small molecule RET kinase inhibitor. Here we report an update on the efficacy and safety of selpercatinib in RET-mutant medullary thyroid cancer (MTC). Methods: Patients with RET-mutant MTC were enrolled to the Phase 1/2 LIBRETTO-001 trial (NCT03157128), a global, multicenter trial (16 countries, 89 sites). Following the Phase 1 dose escalation portion of the trial, patients received the recommended dose of 160 mg orally twice daily. Each cycle was 28 days. The primary endpoint was objective response rate (ORR) per RECIST 1.1. Secondary endpoints included duration of response (DoR) and safety. Per health authority agreement, the primary analysis set was defined as the first 55 consecutively enrolled patients previously treated with multikinase inhibitors cabozantinib and/or vandetanib. Patients naïve to cabozantinib and vandetanib treatment were analyzed separately. All analyses were based on a 16-Dec-2019 data cutoff date. Results: In the primary analysis set of prior cabozantinib and/or vandetanib-treated patients with MTC (n = 55), the ORR by investigator assessment was 62% (95% CI 47.7–74.6, n = 34/55) and the median DoR was not reached (95% CI 18.4 months–not estimable) despite a median follow-up of 14.8 months. In cabozantinib/vandetanib treatment-naïve patients (n = 88), the ORR by investigator assessment was 69% (95% CI 58.6–78.7, n = 61/88, including 2 responses pending confirmation). Of the 59 confirmed responding patients, with a median follow-up of 8 months, responses were ongoing for 57 responders at the time of the analysis. In the safety analysis set consisting of all selpercatinib dosed patients (N = 702), the most common treatment-related adverse events (TRAEs) that occurred in ≥15% of patients were dry mouth (33.3%), increased AST (24.5%), increased ALT (23.8%), hypertension (23.2%), diarrhea (19.7%), and fatigue (16.8%). Only 2% (14 of 702) of patients discontinued selpercatinib for TRAEs. Conclusions: Selpercatinib use was associated with marked and durable antitumor activity in prior cabozantinib and/or vandetanib-treated patients and in cabozantinib/vandetanib-naïve patients with RET-mutant MTC, with the majority of responses ongoing in both cohorts. Selpercatinib was well tolerated. Efficacy data assessed by independent review committee based on the 16-Dec-2019 data cutoff date will be presented. Clinical trial information: NCT03157128 .

Intracranial activity of selpercatinib (LOXO-292) in RET fusion-positive non-small cell lung cancer (NSCLC) patients on the LIBRETTO-001 trial

9516

Background: Patients with RET fusion-positive NSCLC have an ~50% lifetime prevalence of developing central nervous system (CNS) metastases. Selpercatinib is a highly selective oral RET inhibitor with CNS penetration. Its intracranial antitumor activity was previously demonstrated in an orthotopic RET fusion-positive preclinical model. The activity of selpercatinib in RET fusion-positive NSCLC patients with CNS metastases was evaluated as a prespecified subgroup analysis in LIBRETTO-001, a registrational phase 1/2 trial (NCT03157128). Methods: This global (89 sites, 16 countries) trial enrolled patients with advanced RET-altered solid tumors, including patients with RET fusion-positive advanced NSCLC with baseline CNS metastases. The selpercatinib recommended phase 2 dose was 160 mg twice daily, dosed orally in 28-day cycles. CNS metastases were assessed by MRI/CT scan at baseline, then every 8 weeks for 1 year, and every 12 weeks thereafter. The primary endpoint for this analysis was intracranial objective response rate (ORR, confirmed; RECIST v1.1) as assessed by independent review committee (IRC). Secondary endpoints included intracranial duration of response (DoR) by IRC. To be included in the efficacy analysis, patients were required to have adequate follow-up time (opportunity for ≥6 months follow-up from the first dose). Analyses were based on 17Jun2019 data cutoff date. Results: 79 patients with RET fusion-positive NSCLC and baseline CNS metastases were enrolled. Per IRC, 22 of 79 patients had measurable (≥10 mm) CNS disease; 14 of the 22 patients had adequate follow-up time for analysis. This efficacy-evaluable population had a median age of 64 yrs (range 43-80), ECOG PS 0/1 = 21% / 79%, and all had prior systemic therapy. 5 of the 14 patients received prior intracranial radiotherapy; all radiotherapy was completed > 2 months prior to selpercatinib. The intracranial ORR in the 14 patients was 93% (n = 13; 95% CI = 66.1 – 99.8), including 2 complete responses (14%) and 11 partial responses (79%). The median intracranial DoR was 10.1 months (95% CI = 6.7 – NE), with CNS progression events (n = 5) or death (n = 1) reported in 6 of 13 responders. The remaining responders (n = 7) were ongoing and censored. Presentation will include updated IRC data as of 16Dec2019. Conclusions: Selpercatinib had marked intracranial anti-tumor activity in RET fusion-positive NSCLC patients with CNS metastases. Tumor responses were durable, independently-confirmed, and observed in patients with prior systemic chemotherapy. Clinical trial information: NCT03157128 .

Selpercatinib (LOXO-292) in patients with RET-fusion+ non-small cell lung cancer

3584

Background: Selpercatinib (LOXO-292) is a highly selective and potent small molecule RET kinase inhibitor. Here we report an update on the efficacy and safety of selpercatinib in RET-fusion+ non-small-cell lung cancer (NSCLC). Methods: Patients with RET-fusion+ NSCLC were enrolled to the Phase 1/2 LIBRETTO-001 trial (NCT03157128), a global, multicenter trial (16 countries, 89 sites). Following the Phase 1 dose escalation portion of the trial, patients received the recommended dose of 160 mg orally twice daily. Each cycle was 28 days. The primary endpoint was objective response rate (ORR) per RECIST 1.1. Secondary endpoints included duration of response (DoR) and safety. Per health authority agreement, the primary analysis set was defined as the first 105 consecutively enrolled patients previously treated with platinum-based chemotherapy. Treatment-naïve patients were analyzed separately. All analyses were based on a 16-Dec-2019 data cutoff date. Results: In the primary analysis set of platinum-treated patients (median of 3 prior systemic regimens; range 1-15), the ORR by investigator assessment was 70% (95% CI 59.8–78.1, n = 73/105). Responses did not differ by fusion partner or number or type of prior therapies, including anti-PD-1/PD-L1 agents and off-label multikinase inhibitor use. The median DoR was 20.3 months (95% CI 15.6–24.0) with 45 of 73 (62%) responders censored at a median follow-up of 14.8 months. Among 39 treatment-naïve patients, the ORR by investigator assessment was 90% (95% CI 75.8–97.1, n = 35/39, including 2 responses pending confirmation). Median DoR was not reached with 27 of 33 (82%) confirmed responses ongoing at a median follow-up of 7.4 months. In the safety analysis set consisting of all selpercatinib dosed patients (N = 702), the most common treatment-related adverse events (TRAEs) that occurred in ≥15% of patients were dry mouth (33.3%), increased AST (24.5%), increased ALT (23.8%), hypertension (23.2%), diarrhea (19.7%), and fatigue (16.8%). Only 2% (14 of 702) of patients discontinued selpercatinib for TRAEs. Conclusions: Selpercatinib achieved marked and durable antitumor activity in patients with RET-fusion+ NSCLC. Selpercatinib was well tolerated. Efficacy data assessed by independent review committee based on the 16-Dec-2019 data cutoff date will be presented. Clinical trial information: NCT03157128 .

RET Solvent Front Mutations Mediate Acquired Resistance to Selective RET Inhibition in RET-Driven Malignancies

INTRODUCTION

Novel rearranged in transfection (RET)-specific tyrosine kinase inhibitors (TKIs) such as selpercatinib (LOXO-292) have shown unprecedented efficacy in tumors positive for RET fusions or mutations, notably RET fusion-positive NSCLC and RET-mutated medullary thyroid cancer (MTC). However, the mechanisms of resistance to these agents have not yet been described.

METHODS

Analysis was performed of circulating tumor DNA and tissue in patients with RET fusion-positive NSCLC and RET-mutation positive MTC who developed disease progression after an initial response to selpercatinib. Acquired resistance was modeled preclinically using a CCDC6-RET fusion-positive NSCLC patient-derived xenograft. The inhibitory activity of anti-RET multikinase inhibitors and selective RET TKIs was evaluated in enzyme and cell-based assays.

RESULTS

After a dramatic initial response to selpercatinib in a patient with KIF5B-RET NSCLC, analysis of circulating tumor DNA revealed emergence of RET G810R, G810S, and G810C mutations in the RET solvent front before the emergence of clinical resistance. Postmortem biopsy studies reported intratumor and intertumor heterogeneity with distinct disease subclones containing G810S, G810R, and G810C mutations in multiple disease sites indicative of convergent evolution on the G810 residue resulting in a common mechanism of resistance. Acquired mutations in RET G810 were identified in tumor tissue from a second patient with CCDC6-RET fusion-positive NSCLC and in plasma from patients with additional RET fusion-positive NSCLC and RET-mutant MTC progressing on an ongoing phase 1 and 2 trial of selpercatinib. Preclinical studies reported the presence of RET G810R mutations in a CCDC6-RET patient-derived xenograft (from a patient with NSCLC) model of acquired resistance to selpercatinib. Structural modeling predicted that these mutations sterically hinder the binding of selpercatinib, and in vitro assays confirmed loss of activity for both anti-RET multikinase inhibitors and selective RET TKIs.

CONCLUSIONS

RET G810 solvent front mutations represent the first described recurrent mechanism of resistance to selective RET inhibition with selpercatinib. Development of potent inhibitor of these mutations and maintaining activity against RET gatekeeper mutations could be an effective strategy to target resistance to selective RET inhibitors.

A cost-effectiveness analysis of consolidation immunotherapy with durvalumab in stage III NSCLC responding to definitive radiochemotherapy in Switzerland

BACKGROUND

Consolidation immunotherapy with the programmed death ligand 1 (PD-L1) inhibitor durvalumab improves survival in patients with stage III non-small-cell lung cancer responding to radiochemotherapy. The aim of this study was to assess the cost-effectiveness of durvalumab in Switzerland based on the most recent PACIFIC survival follow-up.

MATERIALS AND METHODS

We constructed a Markov model based on the 3-year follow-up data of the PACIFIC trial and compared consolidation durvalumab with observation. We used published utility values and assessed costs for treatment strategies from the perspective of the Swiss health care payers. Cost-effectiveness was tested both in the intention-to-treat population of the PACIFIC trial unselected for PD-L1 tumor expression and in patients with PD-L1-expressing tumors (≥1%).

RESULTS

In the unselected/PD-L1-positive patients, durvalumab showed an incremental effectiveness of 0.76/1.18 quality-adjusted life year (QALY) and incremental costs of Swiss Francs (CHF) 67 239/78 177, resulting in incremental cost-effectiveness ratios of CHF 88 703/66 131 per QALY gained, respectively. The most influential factors for the incremental cost-effectiveness ratio were the utility before first progression, costs for durvalumab, and the hazard ratio for overall survival under durvalumab versus observation. The cost-effectiveness of durvalumab was better than CHF 100 000 per QALY gained in 75% of the simulations in probabilistic sensitivity analysis.

CONCLUSION

Assuming a willingness-to-pay threshold of CHF 100 000 per QALY gained, consolidation durvalumab is likely to be cost-effective both in patients with inoperable stage III non-small-cell lung cancer (NSCLC) unselected for PD-L1 status and in patients with PD-L1-expressing tumors in Switzerland.

Exploratory analysis of front-line therapies in REVEL: a randomised phase 3 study of ramucirumab plus docetaxel versus docetaxel for the treatment of stage IV non-small-cell lung cancer after disease progression on platinum-based therapy

INTRODUCTION

Non-small-cell lung cancer (NSCLC) is a heterogeneous disease. Front-line therapy may affect responses to subsequent treatment regimens, thus influencing second-line therapy decision making. In the randomised phase 3 REVEL study, second-line ramucirumab plus docetaxel (ram+doc) versus docetaxel (doc) improved survival of patients with metastatic NSCLC. We explore efficacy, safety and quality-of-life (QoL) in REVEL based on front-line therapy.

METHODS

Patients were grouped by specific front-line therapy received. Overall survival (OS), progression-free survival (PFS), objective response rate, safety and QoL were assessed descriptively. Kaplan-Meier estimation and Cox proportional hazards modelling were used; frequencies reported in percentages.

RESULTS

Baseline characteristics of 1253 patients were generally well balanced between treatment arms within each front-line therapy subgroup. For patients with non-squamous disease (n=912), induction therapies included platinum-based chemotherapy plus a taxane (n=227; 25%) or pemetrexed (n=449; 49%), with (n=172; 19%) or without bevacizumab. For patients with squamous disease (n=328), induction therapies included platinum-based chemotherapy plus gemcitabine (n=176; 54%) or a taxane (n=69; 21%). A highly selected subgroup (n=127; 14%) received pemetrexed continuation maintenance therapy. Ram+doc improved median OS and PFS versus doc across front-line therapy subgroups, as reflected by HRs ranging from 0.78 to 0.91 and 0.66 to 0.92, respectively, similar to results in the overall intention-to-treat cohort (HRs: 0.86 and 0.76, respectively). High-grade treatment-emergent adverse events of special interest (including neutropenia, febrile neutropenia, leucopenia and hypertension) were generally higher in ram+doc-treated patients relative to doc-treated patients regardless of front-line therapy. No clear differences in safety or QoL were seen across front-line therapy subgroups; outcomes were consistent with those reported in the overall intention-to-treat cohort.

CONCLUSIONS

Results of this exploratory analysis suggest that second-line ram+doc may be effective regardless of prior treatment with platinum-based chemotherapy plus a taxane, pemetrexed, gemcitabine or bevacizumab. Overall, ram+doc is clinically beneficial across a wide range of patients with metastatic NSCLC who have progressed after various front-line therapies.

TRIAL REGISTRATION NUMBER

NCT01168973.

Analysis of Cell-Free DNA from 32,989 Advanced Cancers Reveals Novel Co-occurring Activating RET Alterations and Oncogenic Signaling Pathway Aberrations

PURPOSE

RET is an emerging oncogenic target showing promise in phase I/II clinical trials. An understudied aspect of RET-driven cancers is the extent to which co-occurring genomic alterations exist and how they may impact prognosis or therapeutic response.

EXPERIMENTAL DESIGN

Somatic activating RET alterations were identified among 32,989 consecutive patients with metastatic solid tumors tested with a clinical cell-free circulating tumor DNA (cfDNA) assay. This comprehensive next-generation sequencing (NGS) assay evaluates single-nucleotide variants, and select indels, fusions, and copy number gains in 68-73 clinically relevant cancer genes.

RESULTS

A total of 176 somatic activating RET alterations were detected in 170 patients (143 fusions and 33 missense mutations). Patients had non-small cell lung (NSCLC, n = 125), colorectal (n = 15), breast (n = 8), thyroid (n = 8), or other (n = 14) cancers. Alterations in other oncogenic signaling pathway genes were frequently identified in RET-positive samples and varied by specific RET fusion gene partner. RET fusions involving partners other than KIF5B were enriched for alterations in MAPK pathway genes and other bona fide oncogenic drivers of NSCLC, particularly EGFR. Molecular and clinical data revealed that these variants emerged later in the genomic evolution of the tumor as mechanisms of resistance to EGFR tyrosine kinase inhibitors.

CONCLUSIONS

In the largest cancer cohort with somatic activating RET alterations, we describe novel co-occurrences of oncogenic signaling pathway aberrations. We find that KIF5B-RET fusions are highly specific for NSCLC. In our study, only non-KIF5B-RET fusions contributed to anti-EGFR therapy resistance. Knowledge of specific RET fusion gene partner may have clinical significance.