Cytokine release syndrome caused by antineoplastic treatment with CAR-T and T-cell engaging therapies

T-cell-based immunotherapy has recently evolved as a treatment option for a number of haematological malignancies and is also being developed in solid tumours. A common side effect of chimeric antigen T-cell therapy (CAR-T) and treatment with T-cell engagers is cytokine release syndrome (CRS), which is a potentially life-threatening condition characterized by release of inflammatory mediators. The treatment of CRS is similar to that of other hyper-inflammatory conditions and involves supportive treatment as well as immunosuppressive therapy. The risk of CRS can be mitigated by step-up dosing and immunosuppressive pre-treatment, as argued in this review.

Targeting HER2-mutant metastatic cervical cancer with neratinib: Final results from the phase 2 SUMMIT basket trial

OBJECTIVE

HER2 mutations are associated with poor prognosis and are detected in 3-6% of cervical cancers. Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, had activity in several HER2-mutant cancer types in the phase 2 SUMMIT basket study. We present updated and final results from the cervical cancer cohort of SUMMIT.

METHODS

Eligible patients had HER2-mutant, metastatic or recurrent cervical cancer progressing after platinum-based treatment for advanced/recurrent disease. Patients received neratinib 240 mg/day; loperamide was mandatory during cycle 1. Confirmed objective response rate (ORR) was the primary endpoint. Duration of response (DoR), clinical benefit rate (CBR), progression-free survival (PFS), and safety were secondary endpoints.

RESULTS

Twenty-two patients were enrolled; 18 (81.8%) had endocervical adenocarcinoma; median two prior systemic chemotherapy regimens (range 1-4). The most common HER2 variant was S310F/Y mutation (n = 13; 59.1%). Four patients had confirmed partial responses (ORR 18.2%; 95% CI 5.2-40.3); 6 had stable disease ≥16 weeks (CBR 45.5%; 95% CI 24.4-67.8). Median DoR was 7.6 months (95% CI 5.6-12.3). Median PFS was 5.1 months (95% CI 1.7-7.2). All-grade diarrhea (90.9%), nausea (54.5%), and constipation (54.5%) were the most common adverse events. Five patients (22.7%) reported grade 3 diarrhea. There were no grade 4 adverse events, no diarrhea-related treatment discontinuations, and two grade 5 adverse events, unrelated to neratinib: dyspnea (n = 1) and embolism (n = 1).

CONCLUSIONS

Neratinib resulted in durable responses and disease control in patients with HER2-mutant metastatic/recurrent cervical cancer in SUMMIT. These findings support next-generation sequencing and tailored therapy for select patients with advanced cervical cancer. All responses occurred in patients with endocervical adenocarcinoma. Further assessment of neratinib in this setting is warranted.

TRIAL REGISTRATION NUMBER

NCT01953926 (ClinicalTrials.gov), 2013-002872-42 (EudraCT).

Neratinib + fulvestrant + trastuzumab for HR-positive, HER2-negative, HER2-mutant metastatic breast cancer: outcomes and biomarker analysis from the SUMMIT trial

BACKGROUND

HER2 mutations are targetable alterations in patients with hormone receptor-positive (HR+) metastatic breast cancer (MBC). In the SUMMIT basket study, patients with HER2-mutant MBC received neratinib monotherapy, neratinib + fulvestrant, or neratinib + fulvestrant + trastuzumab (N + F + T). We report results from 71 patients with HR+, HER2-mutant MBC, including 21 (seven in each arm) from a randomized substudy of fulvestrant versus fulvestrant + trastuzumab (F + T) versus N + F + T.

PATIENTS AND METHODS

Patients with HR+ HER2-negative MBC with activating HER2 mutation(s) and prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) therapy received N + F + T (oral neratinib 240 mg/day with loperamide prophylaxis, intramuscular fulvestrant 500 mg on days 1, 15, and 29 of cycle 1 then q4w, intravenous trastuzumab 8 mg/kg then 6 mg/kg q3w) or F + T or fulvestrant alone. Those whose disease progressed on F + T or fulvestrant could cross-over to N + F + T. Efficacy endpoints included investigator-assessed objective response rate (ORR), clinical benefit rate (RECIST v1.1), duration of response, and progression-free survival (PFS). Plasma and/or formalin-fixed paraffin-embedded tissue samples were collected at baseline; plasma was collected during and at end of treatment. Extracted DNA was analyzed by next-generation sequencing.

RESULTS

ORR for 57 N + F + T-treated patients was 39% [95% confidence interval (CI) 26% to 52%); median PFS was 8.3 months (95% CI 6.0-15.1 months). No responses occurred in fulvestrant- or F + T-treated patients; responses in patients crossing over to N + F + T supported the requirement for neratinib in the triplet. Responses were observed in patients with ductal and lobular histology, 1 or ≥1 HER2 mutations, and co-occurring HER3 mutations. Longitudinal circulating tumor DNA sequencing revealed acquisition of additional HER2 alterations, and mutations in genes including PIK3CA, enabling further precision targeting and possible re-response.

CONCLUSIONS

The benefit of N + F + T for HR+ HER2-mutant MBC after progression on CDK4/6is is clinically meaningful and, based on this study, N + F + T has been included in the National Comprehensive Cancer Network treatment guidelines. SUMMIT has improved our understanding of the translational implications of targeting HER2 mutations with neratinib-based therapy.

A first-in-human study of the fibroblast activation protein-targeted, 4-1BB agonist RO7122290 in patients with advanced solid tumors

This first-in-human study evaluated RO7122290, a bispecific fusion protein carrying a split trimeric 4-1BB (CD137) ligand and a fibroblast activation protein α (FAP) binding site that costimulates T cells for improved tumor cell killing in FAP-expressing tumors. Patients with advanced or metastatic solid tumors received escalating weekly intravenous doses of RO7122290 as a single agent (n = 65) or in combination with a 1200-milligram fixed dose of the anti-programmed death-ligand 1 (anti-PD-L1) antibody atezolizumab given every 3 weeks (n = 50), across a tested RO7122290 dose range of 5 to 2000 milligrams and 45 to 2000 milligrams, respectively. Three dose-limiting toxicities were reported, two at different RO7122290 single-agent doses (grade 3 febrile neutropenia and grade 3 cytokine release syndrome) and one for the combination (grade 3 pneumonitis). No maximum tolerated dose was identified. The pharmacokinetic profile of RO7122290 suggested nonlinearity in elimination. The observed changes in peripheral and tissue pharmacodynamic (PD) biomarkers were consistent with the postulated mechanism of action. Treatment-induced PD changes included an increase in proliferating and activated T cells in peripheral blood both in the single-agent and combination arms. Increased infiltration of intratumoral CD8⁺ and Ki67⁺CD8⁺ T cells was observed for both treatment regimens, accompanied by the up-regulation of T cell activation genes and gene signatures. Eleven patients experienced a complete or partial response, six of whom were confirmed to be immune checkpoint inhibitor naive. These results support further evaluation of RO7122290 in combination with atezolizumab or other immune-oncology agents for the treatment of solid tumors.

New pathogenic germline variants identified in mesothelioma

BACKGROUND

Mesothelioma (MM) is associated with asbestos exposure, tumor heterogeneity and aggressive clinical behavior. Identification of germline pathogenic variants (PVs) in mesothelioma is relevant for identifying potential actionable targets and genetic counseling.

METHODS

44 patients underwent whole exome sequencing (WES) or whole genome sequencing (WGS). Germline variants were selected according to association with inherited cancer using a 168-gene in silico panel, and variants classified according to ACMG/AMP classification as pathogenic (class 5) or likely pathogenic (class 4).

RESULTS

In total, 16 patients (36%) were found to carry pathogenic or likely pathogenic variants in 13 cancer associated genes (ATM, BAP1, BRCA2, CDKN2A, FANCA, FANCC, FANCD2, FANCM, MUTYH, NBN, RAD51B, SDHA and XPC). The germline PVs occurred in DNA repair pathways, including homologous recombination repair (HRR) (75%), nucleotide excision repair (6%), cell cycle regulatory (7%), base excision repair (6%), and hypoxic pathway (6%). Five (31%) patients with a germline PV had a first or second degree relative with mesothelioma compared to none for patients without a germline PV. Previously undiagnosed BRCA2 germline PVs were identified in two patients. Potential actionable targets based on the germline PVs were found in four patients (9%).

CONCLUSION

This study revealed a high frequency of germline PVs in patients with mesothelioma. Furthermore, we identified germline PVs in two genes (NBN & RAD51B) not previously associated with mesothelioma. The data support germline testing in mesothelioma and provide a rationale for additional investigation of the HRR pathway as a potential actionable target.

ProTarget: a Danish Nationwide Clinical Trial on Targeted Cancer Treatment based on genomic profiling - a national, phase 2, prospective, multi-drug, non-randomized, open-label basket trial

BACKGROUND

An increasing number of trials indicate that treatment outcomes in cancer patients with metastatic disease are improved when targeted treatments are matched with druggable genomic alterations in individual patients (pts). An estimated 30-80% of advanced solid tumors harbor actionable genomic alterations. However, the efficacy of personalized cancer treatment is still scarcely investigated in larger, controlled trials due to the low frequency and heterogenous distribution of druggable alterations among different histologic tumor types. Therefore, the overall effect of targeted cancer treatment on clinical outcomes still needs investigation.

STUDY DESIGN/METHODS

ProTarget is a national, non-randomized, multi-drug, open-label, pan-cancer phase 2 trial aiming to investigate the anti-tumor activity and toxicity of currently 13 commercially available, EMA-approved targeted therapies outside the labeled indication for treatment of advanced malignant diseases, harboring specific actionable genomic alterations. The trial involves the Danish National Molecular Tumor Board for confirmation of drug-variant matches. Key inclusion criteria include a) measurable disease (RECIST v.1.1), b) ECOG performance status 0-2, and c) an actionable genomic alteration matching one of the study drugs. Key exclusion criteria include a) cancer type within the EMA-approved label of the selected drug, and b) genomic alterations known to confer drug resistance. Initial drug dose, schedule and dose modifications are according to the EMA-approved label. The primary endpoint is objective response or stable disease at 16 weeks. Pts are assigned to cohorts defined by the selected drug, genomic alteration, and tumor histology type. Cohorts are monitored according to a Simon's two-stage-based design. Response is assessed every 8 weeks for the first 24 weeks, then every 12 weeks. The trial is designed similar to the Dutch DRUP and the ASCO TAPUR trials and is a partner in the Nordic Precision Cancer Medicine Trial Network. In ProTarget, serial fresh tumor and liquid biopsies are mandatory and collected for extensive translational research including whole genome sequencing, array analysis, and RNA sequencing.

DISCUSSION

The ProTarget trial will identify new predictive biomarkers for targeted treatments and provide new data and essential insights in molecular pathways involved in e.g., resistance mechanisms and thereby potentially evolve and expand the personalized cancer treatment strategy.

PROTOCOL VERSION

16, 09-MAY-2022.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04341181. Secondary Identifying No: ML41742. EudraCT No: 2019-004771-40.

Extensive genomic analysis in patients with KRAS-mutated solid tumors shows high frequencies of concurrent alterations and potential targets but has limited clinical impact

BACKGROUND

This study aimed to investigate the distribution and frequency of concurrent alterations in different cancers across KRAS subtypes and in different KRAS subtypes across cancers, and to identify potentially actionable targets and patients who received targeted treatment matched to their genomic profile (GP).

MATERIALS AND METHODS

In this descriptive and single-center study, we included 188 patients with solid tumors harboring KRAS mutations in codon 12, 13, 61, 117, or 146, referred to the Phase 1 Unit, Rigshospitalet, Copenhagen, Denmark from mid-2016 to 2020. Genomic co-alterations were detected with whole-exome sequencing, RNA sequencing, SNP array, and mRNA expression array on fresh biopsies. The study is part of the Copenhagen Prospective Personalized Oncology study (NCT02290522).

RESULTS

The majority of patients had colorectal cancer (60.1%), non-small cell lung cancer (11.2%), or pancreatic cancer (10.6%). Most tumors were KRAS-mutated in codon 12 or 13 (93.7%) including G12D (27.1%), G12V (26.6%), G12C (11.7%), and G13D (11.2%). A total of 175 different co-alterations were found, most frequently pathogenic APC and TP53 mutations (55.9% and 46.4%, respectively) and high expression of CEACAM5 (73.4%). Different cancers and KRAS subtypes showed different patterns of co-alterations, and 157 tumors (83.5%) had potentially actionable targets with varying evidence of targetability (assessed using ESMO Scale for Clinical Actionability of molecular Targets). Of the 188 patients included in the study, 15 (7.4%) received treatment matched to their GP (e.g., immunotherapy and synthetic lethality drugs), of whom one had objective partial response according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.

CONCLUSION

Performing extensive genomic analysis in patients with known KRAS-mutated solid tumors may contribute with information to the genomic landscape of cancers and identify targets for immunotherapy or synthetic lethality drugs, but currently appears to have overall limited clinical impact, as few patients received targeted therapy matched to their GP.

Abstract 3254: Multiomics detect potential mechanisms of resistance to BRAF targeted therapy in patients with BRAFV600E mutated solid tumors

Purpose: The purpose of this study was to identify mechanisms of resistance to BRAF targeted therapy using proteomics together with genomics and transcriptomics in patients with BRAFV600E mutated solid tumors.

Experimental procedures: A total of nine patients with BRAFV600E mutated advanced solid tumors (5 with colorectal cancer, 2 with neuroendocrine carcinoma, 1 with cholangiocarcinoma and 1 with breast cancer) treated with BRAF targeted therapy (BRAF inhibitor in combination with either MEK inhibitor and/or EGRF antibody) as part of the Copenhagen Prospective Personalized Oncology study, were included in this study. Tumor biopsies at baseline and at disease progression were analyzed with whole exome/genome sequencing (WES/WGS), transcriptomics (RNA sequencing) and proteomics. Genomic variants were analyzed together with changes in protein expression. Three filtering steps were used to identify potential resistance mechanisms from the proteomics measurements. Proteins were filtered for 1) proteins with a high shift in abundance between baseline and progression 2) proteins with known associations to the patient’s primary cancer based on text-mining and 3) proteins in pathways where BRAF is also involved.

Results: Alterations conferring resistance were identified in 2 out of 9 patients when comparing data from WES/WGS and RNA sequencing at baseline and at disease progression (one patient with PTBP2-BRAF fusion and one with NRAS mutation). Genomic or transcriptomic alterations conferring resistance were not detected in the remaining 7 patients. Notably, there was not a single protein shared between all 9 patients after our filtering, but when comparing overlap on pathway level, six pathways related to RAF and MAPK signaling were affected in all 9 patients. Particularly, paradoxical activation of RAF signaling seems to be an interesting candidate to explain resistance, where formation of RAF dimer structures happens as a response to treatment with BRAF inhibitors, selectively inhibiting BRAF monomer structures (i.e. BRAFV600E).

Conclusion: With a multiomic approach using proteomics together with genomics and transcriptomics, potential mechanisms of resistance were detected in all patients at disease progression, where resistance to BRAF targeted therapies had occurred. Six mechanisms of resistance were shared independently of diagnosis and BRAF inhibitor combination regimes. The potential of integrating proteomics with genomics and transcriptomics is promising and may potentially guide therapy for future patients with treatment resistant BRAFV600E mutated solid tumors.

Citation Format: Martina Eriksen, Annelaura Bach Nielsen, Filip Mundt, Josephine Kerzel Duel, Matthias Mann, Ulrik Lassen, Christina Westmose Yde, Camilla Qvortrup, Martin Højgaard, Iben Spanggaard, Kristoffer Staal Rohrberg. Multiomics detect potential mechanisms of resistance to BRAF targeted therapy in patients with BRAFV600E mutated solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3254.

Abstract 2276: High frequency of pathogenic germline variants in patients with malignant mesothelioma

Background: Malignant mesothelioma (MM) is associated with asbestos exposure, tumor heterogeneity and aggressive clinical behavior. Identification and characterization of germline variants in malignant mesothelioma is relevant for identifying potential actionable targets and genetic counseling of family members.

Methods: Patients referred to the Phase I Unit at Rigshospitalet were prospectively enrolled into the Copenhagen Prospective Personalized Oncology trial and underwent whole exome sequencing for somatic and germline variants. Between January 2014 and September 2021, 45 patients with MM were identified and 40 patients underwent whole exome sequencing. Germline variants were selected according to association to inherited cancer using a 168-gene panel and variants were classified according to ACMG/AMP classification as pathological (class 5) or likely pathogenic (class 4).

Results: 34 males (85%) and 6 females (15%) with a median age of 64 years (range: 43-77) were available for analysis. The majority (85%) had malignant pleural mesothelioma whilst the rest (15%) had malignant peritoneal mesothelioma. Histological subtypes were distributed between epithelioid type (N=24, 60%), biphasic type (N=12, 30%) and the sarcomatoid type (N=4, 10%).

A pathogenic or likely pathogenic variant was found in 16 patients (40%). In total 13 different germline variants were identified (ATM, BAP1, BRCA2, CDKN2A, FANCA, FANCC, FANCD2, FANCM, MUTYH, NBN, RAD51B, SDHA and XPC). The variants included five frameshifts (33%), four missenses (25%), four nonsenses (25%), one splice site (6%), one start loss (6%) and one synonymous (6%).

The pathogenic germline variants were found in DNA repair pathways, including homologous recombination repair (69%), nucleotide excision repair (13%), cell cycle regulatory (6%), DNA damage checkpoint control (6%) and hypoxic pathway (6%). Three (19%) of the patients with a germline variant had a second cancer. A previously undiagnosed BRCA2 germline mutation was found in 2 patients. A potential treatment target based on the pathogenic germline variant could be suggested in four patients (10%).

Conclusion: The current analysis revealed a high frequency of pathogenic germline variants in patients with malignant mesothelioma. These data support germline testing in these patients and provide a rationale for additional investigation of the homologous recombination pathway as a potential target for precision medicine.

Citation Format: Laila Belcaid, Birgitte Bertelsen, Karin A. Wadt, Ida V. Tuxen, Iben Spanggaard, Martin Højgaard, Jens B. Sørensen, Ulrik Lassen, Finn C. Nielsen, Kristoffer Rohrberg, Christina W. Yde. High frequency of pathogenic germline variants in patients with malignant mesothelioma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2276.

Targeting HER2 mutation–positive advanced biliary tract cancers with neratinib: Final results from the phase 2 SUMMIT basket trial

4079

Background: HER2 mutations are infrequent genomic events in biliary tract cancers (BTCs) and are associated with poor overall survival (OS) in patients with metastatic disease. HER2 overexpression is associated with an increased risk of disease recurrence in patients with resected BTC. There is limited data on targeting HER2 in BTC harboring activating somatic HER2 mutations. Neratinib, an irreversible, pan-HER, oral tyrosine kinase inhibitor, interferes with constitutive receptor kinase activation and has demonstrated activity in several HER2-mutant solid tumors. Methods: SUMMIT is an open-label, single-arm, multi-cohort, phase 2, ‘basket’ trial of neratinib in patients with solid tumors harboring oncogenic HER2 somatic mutations. The primary objective of the BTC cohort was to estimate objective response rate (ORR). Secondary objectives were clinical benefit rate (CBR), progression-free survival (PFS), OS, response duration, safety, and tolerability. Retrospective central confirmation of locally reported HER2 mutation (next-generation sequencing on archival or fresh tumor tissue using MSK-IMPACT or in cfDNA extracted from plasma by MSK-ACCESS) and association with outcome was an exploratory endpoint. This trial is registered with ClinicalTrials.gov (NCT01953926). Results: 25 treatment-refractory patients with metastatic BTC were enrolled (11 cholangiocarcinoma, 10 gallbladder, 4 ampullary cancers). ORR was 16% (95% CI 4.5–36.1%) and CBR was 28% (95% CI 12.1–49.4%). Median PFS and OS were 2.8 (95% CI 1.1–3.7) and 5.4 (95% CI 3.7–11.7) months, respectively. Median PFS for the gallbladder, cholangiocarcinoma and ampulla cohorts was 3.7 (95% CI 0.8–6.4), 1.4 (95% CI 0.5–9.1), and 1.1 (95% CI 1.1–3.8) months, respectively. Corresponding median OS values in these cohorts were 9.8 (95% CI 2.4–NE), 5.4 (95% CI 0.8–16.2), and 5.0 (95% CI 3.7–10.2) months, respectively. Central mutation confirmation was feasible for 23 of 25 patients; 22 were concordant with enrolment assays. The most common HER2 mutations were S310F (n = 11; 48%) and V777L (n = 4; 17%). Exploratory analyses suggested worse outcomes for HER2-mutant tumors with co-occurring oncogenic TP53 and CDKN2A alterations. Loss of amplified HER2 S310F and acquisition of multiple previously undetected oncogenic co-mutations were identified at progression in one of four responders. Diarrhea (56% any grade) was the most common toxicity. Conclusions: Neratinib is tolerable with modest antitumor activity in patients with BTC harboring HER2 mutations. Although the primary endpoint was met, future studies should evaluate rational combinations to augment and/or prolong responses. Clinical trial information: NCT01953926.

Neratinib plus fulvestrant plus trastzuzumab (N+F+T) for hormone receptor-positive (HR+), HER2-negative, HER2-mutant metastatic breast cancer (MBC): Outcomes and biomarker analysis from the SUMMIT trial

1028

Background: N is an oral, irreversible pan-HER TKI with activity against HER2 mutations. Genomic analyses from the SUMMIT MBC cohort following N±F suggest that resistance to N may occur via mutant allele amplification or secondary HER2 mutations. Adding T to N+F in SUMMIT showed encouraging durable responses in patients (pts) with HR+, HER2-mutant MBC and prior CDK4/6 inhibitors (CDK4/6i). Methods: SUMMIT (NCT01953926) enrolled pts with HR+, HER2-negative MBC with activating HER2 mutation(s) and prior CDK4/6i. Pts received N+F+T (oral N 240 mg/d with loperamide prophylaxis, im F 500 mg d1&15 of cycle 1 then q4w, iv T 8 mg/kg initially then 6 mg/kg q3w). During the small, randomized portion of the trial, pts received N+F+T, F+T or F (1:1:1 ratio). Pts randomized to F+T or F could crossover to N+F+T at progression. Efficacy endpoints: investigator-assessed ORR and CBR (RECIST v1.1); DOR; best overall response. Pre-treatment tumor tissue was centrally assessed retrospectively by next-generation sequencing. ctDNA from patient samples was assessed by NGS. Results: SUMMIT has completed enrolment; we report efficacy from 45 pts in the N+F+T cohort, plus 10 pts who progressed on F (n=6) or F+T (n=4) and crossed over to N+F+T (Table). HER2 allelic variants in the 45 N+F+T pts and ORR (%) (pts may have >1 mutation) were: V777L (n=6, 50%), L755S/P (n=15, 40%), S310F (n=4, 50%), exon 20 insertion (n=11, 36%), other KD missense (n=6, 33%), TMD missense (n=2, 0%), exon 19 deletion (n=1, 0%). Conclusions: N+F+T is a promising combination for HR+, HER2-mutated MBC with prior exposure to CDK4/6i, across a range of activating HER2 mutations. Results from the upcoming Apr 2022 data cut, including biomarkers, safety, mechanisms of acquired resistance, and preclinical mechanism of N+T, will be presented. Clinical trial information: NCT01953926. [Table: see text]

First-in-human phase 1 dose-escalation study of CAN04, a first-in-class interleukin-1 receptor accessory protein (IL1RAP) antibody in patients with solid tumours

BACKGROUND

Interleukin-1 (IL-1) signalling is involved in various protumoural processes including proliferation, immune evasion, metastasis and chemoresistance. CAN04 is a first-in-class monoclonal antibody that binds IL-1 receptor accessory protein (IL1RAP), required for IL-1 signalling. In this first-in-human phase 1 study, we assessed safety, recommended phase 2 dose (RP2D), pharmacokinetics, pharmacodynamics and preliminary anti-tumour activity of CAN04 monotherapy.

METHODS

Patients with advanced solid tumours known to express IL1RAP and refractory to standard treatments were enrolled in a dose-escalation study with 5 dose levels (1.0-10.0 mg/kg) of weekly CAN04.

RESULTS

Twenty-two patients were enrolled. Most common adverse events were infusion-related reactions (41%), fatigue (32%), constipation (27%), diarrhoea (27%), decreased appetite (23%), nausea (23%) and vomiting (23%). One dose limiting toxicity was reported. No maximum tolerated dose was identified. Pharmacokinetics analyses indicate higher exposures and slower elimination with increasing doses. Decreases in serum IL-6 and CRP were observed in most patients. Twenty-one patients were evaluable for response, 43% had stable disease per immune-related response criteria with no partial/complete responses.

CONCLUSIONS

The IL1RAP targeting antibody CAN04 can be safely administered to patients up to 10.0 mg/kg weekly, which was defined as the RP2D. Serum biomarkers supported target engagement and IL-1 pathway inhibition.

CLINICAL TRIAL REGISTRATION

NCT03267316.

Precision patients: Selection practices and moral pathfinding in experimental oncology

This paper addresses selection practices in a Danish phase 1 unit specialised in precision medicine in the field of oncology. Where precision medicine holds the ambition of selecting genetically fit medicine for the patient, we find that precision medicine in the early trial setting is oriented towards selecting clinically and genetically fit patients for available treatment protocols. Investigating how phase 1 oncologists experience and respond to the moral challenges of selecting patients for early clinical trials, we show that inclusion criteria and patient categories are not always transparent to patients. Lack of transparency about inclusion criteria has been interpreted as morally problematic. Yet drawing on social science studies of 'unknowing', we argue that silence and non-transparency in interactions between oncologists and patients are crucial to respect the moral agency of patients at the edge of life and recognise them as belonging to the public of Danish health care. In the discussion, we consider the practice of placing 'unfit' patients on a waiting list for trial participation. Rather than representing an ethical and political problem, we argue, the waiting list can act as a valve enabling oncologists to navigate the scientific and as well as the moral uncertainties in phase 1 oncology.

Modeling Metastatic Colonization in a Decellularized Organ Scaffold-Based Perfusion Bioreactor

Metastatic cancer spread is responsible for most cancer-related deaths. To colonize a new organ, invading cells adapt to, and remodel, the local extracellular matrix (ECM), a network of proteins and proteoglycans underpinning all tissues, and a critical regulator of homeostasis and disease. However, there is a major lack in tools to study cancer cell behavior within native 3D ECM. Here, an in-house designed bioreactor, where mouse organ ECM scaffolds are perfused and populated with cells that are challenged to colonize it, is presented. Using a specialized bioreactor chamber, it is possible to monitor cell behavior microscopically (e.g., proliferation, migration) within the organ scaffold. Cancer cells in this system recapitulate cell signaling observed in vivo and remodel complex native ECM. Moreover, the bioreactors are compatible with co-culturing cell types of different genetic origin comprising the normal and tumor microenvironment. This degree of experimental flexibility in an organ-specific and 3D context, opens new possibilities to study cell-cell and cell-ECM interplay and to model diseases in a controllable organ-specific system ex vivo.

Immune Cell Profiling of Peripheral Blood as Signature for Response During Checkpoint Inhibition Across Cancer Types

Despite encouraging results with immune checkpoint inhibition (ICI), a large fraction of cancer patients still does not achieve clinical benefit. Finding predictive markers in the complexity of the tumor microenvironment is a challenging task and often requires invasive procedures. In our study, we looked for putative variables related to treatment benefit among immune cells in peripheral blood across different tumor types treated with ICIs. For that, we included 33 patients with different solid tumors referred to our clinical unit for ICI. Peripheral blood mononuclear cells were isolated at baseline, 6 and 20 weeks after treatment start. Characterization of immune cells was carried out by multi-color flow cytometry. Response to treatment was assessed radiologically by RECIST 1.1. Clinical outcome correlated with a shift towards an effector-like T cell phenotype, PD-1 expression by CD8+T cells, low levels of myeloid-derived suppressor cells and classical monocytes. Dendritic cells seemed also to play a role in terms of survival. From these findings, we hypothesized that patients responding to ICI had already at baseline an immune profile, here called ‘favorable immune periphery’, providing a higher chance of benefitting from ICI. We elaborated an index comprising cell types mentioned above. This signature correlated positively with the likelihood of benefiting from the treatment and ultimately with longer survival. Our study illustrates that patients responding to ICI seem to have a pre-existing immune profile in peripheral blood that favors good outcome. Exploring this signature can help to identify patients likely to achieve benefit from ICI.

Abstract PD1-05: Latest findings from the breast cancer cohort in SUMMIT - a phase 2 ‘basket’ trial of neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer

Background: HER2 mutations are oncogenic in hormone receptor positive (HR+) metastatic breast cancer (MBC), and may confer resistance to prior endocrine therapy but retain sensitivity to neratinib. Neratinib is an oral, irreversible, pan-HER tyrosine kinase inhibitor with clinical activity either as a single agent or in combination with fulvestrant in HER2-mutated, HER2-non-amplified MBC. Genomic analyses suggest that acquired resistance to neratinib can occur via additional HER2 alterations, which may alter HER2-pathway signaling. We investigated whether dual HER2-targeted therapy could improve clinical benefit in a cohort of patients with HER2-mutant, HR+ MBC treated with neratinib + trastuzumab + fulvestrant (N+T+F) from SUMMIT - a phase 2 basket trial (NCT01953926).

Methods: Patients with HR+ MBC with known or suspected pathogenic HER2 mutation(s) identified by genomic sequencing were eligible to receive N+T+F (oral neratinib 240 mg/day, i.v. trastuzumab 8 mg/kg initially followed by 6 mg/kg every 3 weeks, and i.m. fulvestrant 500 mg on days 1&15 of month 1, then on day 1 every 4 weeks). Loperamide prophylaxis was mandatory during the first 2 treatment cycles. There was no restriction on the number of prior lines of systemic treatment for MBC. Efficacy endpoints: confirmed objective response rate and clinical benefit rate (RECIST v1.1); duration of response; progression-free survival.

Results: As of 22-May-2020, 46 patients were enrolled in the N+T+F cohort and received at least 1 dose of study medication (safety population). 14 unique HER2 allelic variants were identified: 8 kinase domain missense; 1 extracellular domain missense; 2 transmembrane domain missense; 2 exon-20 insertion; 1 exon-19 deletion. The most common HER2 mutant variant was L755S (n=15, 33%) Median number of prior systemic regimens for metastatic disease was 4 (range 0-10); 34 (74%) patients had received prior fulvestrant, and 31 (67%) patients had received prior cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor therapy. 16 (35%) patients had ductal histology, 29 (63%) had lobular carcinoma, and 1 (2%) had mixed ductal and lobular carcinoma. At this time, 30/46 patients had RECIST measurable disease and are efficacy evaluable (ongoing patients who did not have the opportunity for their first post-baseline tumor assessment were excluded); clinical activity - see Table. Diarrhea was the most commonly reported adverse event (80% any grade) with 15 (33%) patients reporting grade 3 diarrhea (no grade 4 diarrhea). 10 patients (22%) had a neratinib dose reduction due to diarrhea but no patients discontinued treatment due to diarrhea.

Conclusions: The combination of N+T+F demonstrated encouraging clinical activity in heavily pre-treated HER2-mutant, HR+, HER2-non-amplified MBC, including patients who had previously received either fulvestrant and/or CDK4/6 inhibitor-based therapies. While the rate of grade 3 diarrhea was higher than that observed with single-agent neratinib in SUMMIT, this was manageable through loperamide prophylaxis, and no patients discontinued study treatment due to diarrhea. SUMMIT has recently been amended to evaluate N+T+F, T+F and F (1:1:1 randomization) and continues to enroll patients.

RECIST measurable and efficacy evaluable patients (n=30)Confirmed objective response,a n (%)12 (40)CR0PR12ORR, % (95% CI)40 (23-59)Best overall response, n (%)18 (60)CR0PR18Best overall response rate, % (95% CI)60 (41-77)Medianb DOR, months (95% CI)8.4 (4.1-NE)Clinical benefit,c n (%)14 (47)CR or PR12SD ≥24 weeks2CBR, % (95% CI)47 (28-66)Medianb PFS, months (95% CI)8.3 (4.2-12.5)aORR is defined as either a CR or a PR that is confirmed no less than 4 weeks after the criteria for response are initially met; bKaplan-Meier analysis; cCBR is defined as confirmed CR or PR or SD for ≥24 weeks; CR, complete response; CBR, clinical benefit rate; DOR, duration of response; NE, not estimable; ORR, objective response rate; PFS, progression-free survival; PR, partial response; SD, stable disease.

Citation Format: Komal Jhaveri, Cristina Saura, Angel Guerrero-Zotano, Iben Spanggaard, François-Clement Bidard, Jonathan W Goldman, José A García-Sáenz, Andrés Cervantes, Valentina Boni, John Crown, Adam Brufsky, Sherene Loi, Barbara Haley, Ingrid A Mayer, Stephen Chia, Janice Lu, James Waisman, Noa Efrat Ben-Baruch, Mark E Burkard, Jennifer M Suga, Lucía González-Cortijo, Bruno Perrucci, Feng Xu, Sofia Wong, Jie Zhang, Lisa D Eli, Alshad S Lalani, Hans Wildiers. Latest findings from the breast cancer cohort in SUMMIT - a phase 2 ‘basket’ trial of neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD1-05.

Targeting HER2 (ERBB2) mutation-positive advanced biliary tract cancers with neratinib: Results from the phase II SUMMIT ‘basket’ trial

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Background: Genomic profiling studies have reported somatic HER2 mutations in ~2–5% of biliary tract cancers (BTC). Clinical data from the SUMMIT study demonstrate that neratinib, a pan-HER irreversible tyrosine kinase inhibitor, has encouraging clinical activity in multiple types of HER2-mutant solid tumor malignancies. Methods: SUMMIT is a multi-histology, open-label, phase II ‘basket’ study of neratinib in patients with somatic HER2 mutations (ClinicalTrials.gov NCT01953926). Patients with activating somatic HER2 mutations with different histologies, including BTC, received neratinib monotherapy (240 mg oral daily). Loperamide prophylaxis was mandatory during cycle 1. Efficacy endpoints: objective response rate (ORR, RECIST v1.1); clinical benefit rate (CBR); duration of response; progression-free survival (PFS). Adverse events (AEs) were assessed by CTCAE v4.0. Genomic profiling from fresh/archival tumor tissues and/or plasma cfDNA was performed retrospectively by next-generation sequencing (MSK-IMPACT). Results: As of 3-Sep-2020, 25 patients with HER2-mutant BTC were enrolled: gallbladder (40%); intrahepatic (24%); extrahepatic (20%); ampulla of Vater (16%). 68% of patients received ≥2 systemic regimens (96% received prior gemcitabine-based regimens). The S310F/Y variant accounted for nearly half of HER2 mutations (n=11). Other HER2 mutations: V777L (n=5); L755S (n=2); V842I (n=2); R678Q (n=2). Confirmed ORR in 25 evaluable patients was 12% (95% CI 3–31%) and CBR was 20% (95% CI 7–41%), including 3 confirmed PRs and 2 patients with SD for ≥16 weeks. Tumor shrinkage was observed in multiple HER2-activating mutations and enriched in gallbladder and extrahepatic subtypes of BTC. Median PFS was 2.8 (95% CI 1.1–3.7) months; median overall survival (OS) was 5.4 (95% CI 3.7–11.7) months. Nine (36%) patients (3 of whom with ECOG PS 2) came off study within 28 (range 6–47) days of treatment due to clinical deterioration (unrelated to study drug) followed by death. The most common treatment-related AEs (any grade) were diarrhea (56%) and vomiting (48%). Diarrhea was the most common Grade 3 event (24%); 4 patients (16%) required a neratinib dose reduction; no patients discontinued treatment due to diarrhea. Conclusions: Neratinib is safe and tolerable in patients with advanced BTC patients and somatic HER2 mutations. The antitumor activity of neratinib appears comparable to current standards of care, with similar PFS and OS in heavily pretreated patients. Analysis of co-occurring oncogenic mutations and response is ongoing, and consideration is being given to neratinib-based combination regimens to further improve outcomes in this setting. Clinical trial information: NCT01953926.

Common phenotypic dynamics of tumor-infiltrating lymphocytes across different histologies upon checkpoint inhibition: impact on clinical outcome

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the cancer therapeutic landscape and our perception of interactions between the immune system and tumor cells. Despite remarkable progress, disease relapse and primary resistance are not uncommon. Understanding the biological processes that tumor-infiltrating lymphocytes (TILs) undergo during ICI, how this affects the tumor microenvironment (TME) and, ultimately, clinical outcome is, therefore, necessary to further improve treatment efficacy.

AIM

In the current study, we sought to characterize TILs from patients with metastatic solid tumors undergoing ICI correlating flowcytometric findings with clinical outcome.

METHODS

In total, 20 patients with 10 different metastatic solid tumors treated with ICIs targeting programmed-cell death-1 (PD-1)/PD-L1 axis were included in this study. The phenotype of T cells deriving from biopsies obtained prior to treatment initiation and on-treatment was investigaded. Analyses were focused on T cells' degree of differentiation and activity and how they correlate with transcriptomic changes in the TME.

RESULTS

Data indicate that patients benefitting from ICIs accumulate CD8+central memory T cells. TILs developed an effector-like phenotype over time, which was also associated with a cytolytic gene signature. In terms of modulation of T-cell responses, we observed that high expression of checkpoint molecules pre-treatment (i.e., PD-1, lymphocyte activation gene-3 [LAG-3], B and T-lymphocyte attenuator [BTLA] and T-cell immunoglobulin and mucin domain containing-3 [TIM-3]) was associated with similar gene signature and correlated to treatment benefit. Increasing expression of LAG-3 and BTLA in the CD8 compartment and their co-expression with PD-1 during treatment were, however, a common feature for patients who failed to respond to ICIs.

CONCLUSIONS

Besides identifying immune profiles suggestive of response to ICI, our results provide a more nuanced picture regarding expression of checkpoint molecules that goes beyond T-cell anergy.

Abstract P1-19-05: Capivasertib (AZD5363) in combination with fulvestrant in PTEN-mutant ER+ metastatic breast cancer

Background: Loss of function in the tumor suppressor gene, PTEN, activates PI3K/AKT signaling, driving tumor growth. Somatic mutations in PTEN occur in 5-10% of estrogen-receptor-positive (ER+) breast cancer (BC), and PTEN loss/inactivation is associated with an aggressive BC phenotype and poor outcome. Capivasertib, a pan-AKT kinase inhibitor, has shown antitumor activity in solid tumors. In ER+ BC, suppression of PI3K/AKT signaling results in a compensatory increase in ER-dependent transcription, potentially limiting the efficacy of AKT inhibitors when given as monotherapy. We therefore investigated concurrent inhibition of AKT and ER with combination therapy of capivasertib and fulvestrant in PTEN-mutant ER+ metastatic BC (MBC).

Methods: In an expansion cohort (part F) of a Phase I study (NCT01226316), oral capivasertib 400 mg twice daily, 4 days on 3 days off, and fulvestrant at labeled dose, was administered to ER+ MBC patients (pts) with tumors harboring a deleterious PTEN alteration (identified in tissue/plasma by local next-generation sequencing [NGS], with central NGS and immunohistochemistry [IHC] performed retrospectively). Pts were enrolled in fulvestrant-naïve (FN) or fulvestrant-resistant (FR) cohorts (max 24 pts/cohort). Key objectives included safety and efficacy based on 24-week clinical benefit rate (CBR).

Results: At data cut-off, 31 pts (12 FN; 19 FR) received treatment. Median number of prior metastatic regimens was 7. FN pts had higher rates of visceral disease (100%) and prior chemotherapy receipt (median 4 [range 0-8]) than FR pts (84%; median 2 [1-7]), respectively]. CBR and median progression-free survival (PFS) were 17% and 2.6 months in FN pts, and 37% and 4.1 months in FR pts, respectively (Table). Twenty-four patients (77%) had PTEN mutations and 7 (23%) had PTEN gene deletions determined by local NGS. Central plasma NGS confirmed 79% (19/24) of the PTEN mutations, and IHC confirmed complete loss of the PTENprotein in 85% (22/26) of cases. Treatment-related grade ≥3 adverse events (AEs) occurred in 32%, most frequently diarrhea and maculopapular rash (both n=2 pts). Treatment-related AEs resulted in dose reduction in 2 pts.

Table. Clinical efficacyFN, n=12FR, n=19ORR, % (95% CI)8 (0.2, 39)21 (6, 46)CBR, % (95% CI)17 (2, 48)37 (16, 62)Confirmed response, n (%)1 (8)4 (21)Stable disease ≥24 weeks, n (%)2 (17)3 (16)Median PFS, months (95% CI)2.6 (1.2–4.2)4.1 (1.5–6.7)Median duration of response, months (95% CI)5.5 (NC–NC)6.9 (1.4–NC)Data cut-off was 21 March 2019. Median time from last fulvestrant administration to study entry in FR pts (n=19) was 13.8 months (range 0.7–28.2). CBR was defined as confirmed responders and those with stable disease ≥24 weeks. NC, not calculable (because of limited pt numbers); ORR, objective response rate

Conclusions: Capivasertib plus fulvestrant is clinically active in heavily pretreated PTEN-mutated ER+ MBC, including in pts with prior resistance to fulvestrant. Efficacy appeared marginally better in FR than FN pts, possibly due to enrichment of pts with more aggressive disease in the FN cohort. Further analyses of the relationship between genomic features, such as concurrent mutations with drug activity, will be reported.

Citation Format: Lillian M Smyth, Gerald Batist, Funda Meric-Bernstam, Peter Kabos, Iben Spanggaard, Ana Lluch, Alison Schram, Andrea Varga, Andrea Wong, Helen Ambrose, Alan Barnicle, T. Hedley Carr, Elza C de Bruin, Carolina Salinas-Souza, Andrew Foxley, Joana Hauser, Justin PO Lindemann, Rhiannon Maudsley, Robert McEwen, Michele Moschetta, Martine Roudier, Gaia Schiavon, Pedram Razavi, Udai Banerji, Sarat Chandarlapaty, José Baselga, David M Hyman. Capivasertib (AZD5363) in combination with fulvestrant in PTEN-mutant ER+ metastatic breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-05.

Abstract P1-19-08: Neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer: Updated results from the phase 2 SUMMIT ‘basket’ trial

Background: HER2 mutations define a subset of metastatic breast cancers (MBCs) with a unique mechanism of oncogenic addiction to HER2 signaling. Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, has been shown to have encouraging clinical activity when combined with fulvestrant in HER2-mutant, hormone receptor-positive (HR+) MBC [Smyth et al. SABCS 2018]. Genomic analyses suggest that acquired resistance to neratinib may occur by the acquisition of additional HER2 alterations, which may amplify HER2 pathway signaling [Won et al. AACR 2019]. We therefore explored whether dual HER2-targeted therapy may improve clinical benefit in this setting. Here we describe initial results from a cohort of patients with HER2-mutant, HR+ MBC treated with neratinib + trastuzumab + fulvestrant (N+T+F) from the phase 2 SUMMIT ‘basket’ trial (NCT01953926). Methods: Patients with HR+ MBC and known oncogenic driver HER2 mutations identified by genomic sequencing were eligible to receive combination treatment with oral neratinib 240 mg daily, intravenous trastuzumab 8 mg/kg initially followed by 6 mg/kg every 3 weeks, and intramuscular fulvestrant 500 mg on days 1 and 15 of month 1, then on day 1 every 4 weeks (N+T+F). Loperamide prophylaxis was mandatory during cycle 1. There was no restriction on the number of prior lines of systemic treatment for MBC. Efficacy endpoints included: confirmed objective response rate and clinical benefit rate - all defined according to RECIST v1.1 - as well as duration of response and progression-free survival. Genomic profiling from fresh/archival tumor tissues and/or plasma cfDNA was performed retrospectively by next-generation sequencing (MSK-IMPACT). Results: As of 01-May-2019, 19 patients were enrolled into the N+T+F cohort and received study treatment (safety population). 20 HER2 mutations were identified in the 19 patients: 14 kinase domain missense mutations, 3 extracellular domain missense mutations, and 3 exon-20 insertion mutations. Median number of prior systemic regimens for metastatic disease was 4 (range 0-10) and histologies were evenly split between lobular and ductal carcinomas. While the majority of patients remain on study treatment (n=15), only 13 of the 19 enrolled patients are efficacy evaluable at this time (having had ≥1 post-baseline tumor assessment). Clinical activity is summarized in the Table. Diarrhea was the most commonly reported adverse event (84.2% any grade) with 5 patients reporting Grade 3 diarrhea (there were no Grade 4 diarrhea events). Three patients (15.8%) reduced neratinib dose due to diarrhea but no patient discontinued treatment due to diarrhea. Conclusions: The combination of N+T+F resulted in an encouraging response rate and was a well-tolerated regimen in predominantly heavily pretreated HER2-mutant HR+ breast cancers. Based on a pre-planned interim analysis, the cohort has been expanded to enroll a total of 50 patients. Updated efficacy and safety data will be presented.

Neratinib + trastuzumab + fulvestrant(n=13)Confirmed objective response rate, % (95% CI)39 (13.9-68.4)Complete response0Partial response5 (39)Duration of responses range, months4.2*-10.4*Median progression-free survivala,b, months (95% CI)NA (1.9-NA)*Response ongoing; aKaplan-Meier analysis; bincludes all patients enrolled (n=19); NA, not applicable.

Citation Format: Hans Wildiers, Valentina Boni, Cristina Saura, Mafalda Oliveira, Komal Jhaveri, Helen Won, François-Clément Bidard, Adam M Brufsky, Mark E Burkard, Andrés Cervantes, Carlos Fernández-Martos, Barbara Haley, Sherene Loi, Iben Spanggaard, Stefano Panni, Janice Lu, Melanie E Dujka, Feng Xu, Sonia Macia, Lisa D Eli, Alshad S Lalani, Sarina Piha-Paul, Funda Meric-Bernstam, David B Solit, David M Hyman. Neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer: Updated results from the phase 2 SUMMIT ‘basket’ trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-08.

Efficacy and Determinants of Response to HER Kinase Inhibition in HER2-Mutant Metastatic Breast Cancer

HER2 mutations define a subset of metastatic breast cancers with a unique mechanism of oncogenic addiction to HER2 signaling. We explored activity of the irreversible pan-HER kinase inhibitor neratinib, alone or with fulvestrant, in 81 patients with HER2-mutant metastatic breast cancer. Overall response rate was similar with or without estrogen receptor (ER) blockade. By comparison, progression-free survival and duration of response appeared longer in ER⁺ patients receiving combination therapy, although the study was not designed for direct comparison. Preexistent concurrent activating HER2 or HER3 alterations were associated with poor treatment outcome. Similarly, acquisition of multiple HER2-activating events, as well as gatekeeper alterations, were observed at disease progression in a high proportion of patients deriving clinical benefit from neratinib. Collectively, these data define HER2 mutations as a therapeutic target in breast cancer and suggest that coexistence of additional HER signaling alterations may promote both de novo and acquired resistance to neratinib. SIGNIFICANCE: HER2 mutations define a targetable breast cancer subset, although sensitivity to irreversible HER kinase inhibition appears to be modified by the presence of concurrent activating genomic events in the pathway. These findings have implications for potential future combinatorial approaches and broader therapeutic development for this genomically defined subset of breast cancer.This article is highlighted in the In This Issue feature, p. 161.

[Trends in oncological phase I trials]

This review summarises the current knowledge of anticancer therapy. More than 1,100 cancer drugs are currently under development in the United States. The increasing biological insight and platforms for high throughput screening of drugs have changed the developmental landscape of anticancer therapies from classical cytotoxic agents to targeted agents and immunotherapy. There is an increasing number of targeted agents, which are only efficacious in tumours harbouring specific genomic alterations in early clinical development. Furthermore, the landscape of immunotherapy broadens, and personalised immunotherapy is in development. The integration of genomic testing into early clinical oncology trials is increasing.

Abstract CT229: Olaparib in patients (pts) with previously treated, homologous recombination repair mutation (HRRm) or homologous recombination deficiency (HRD)-positive advanced cancer: Phase II LYNK-002 study

Background: Human cancers are associated with defects in DNA damage repair (DDR). Evidence suggests a key role for poly(ADP-ribose) polymerases (PARPs) in repairing certain DNA damage lesions. Olaparib (a PARP inhibitor) is approved for pts with germline BRCA1 and BRCA2-mutated breast and ovarian cancers, and pts with or without BRCA mutation in recurrent ovarian cancer. Mutations in HRR genes (HRRm; beyond BRCA1 or BRCA2) and HRD may sensitize tumors to respond to PARP inhibitors. Olaparib has also shown favorable ORRs in HRRm/HRD-positive (HRD+) cancers, including prostate and ovarian. Thus, this study (NCT03742895) aims to evaluate the use of HRRm/HRD+ as biomarkers of tumor-agnostic response to olaparib monotherapy.

Methods: Eligibility for this open-label, Phase II study requires pts ≥18 years of age with a previously treated, histologically/cytologically confirmed, HRRm/HRD+ advanced solid tumor; who have failed, are intolerant to, or ineligible for all available standard of care therapies; with no disease progression during prior platinum-based treatment. At baseline, pts should also have measurable disease per RECIST v1.1 or Prostate Cancer Working Group (PCWG)-modified RECIST v1.1 (for pts with prostate cancer) without CNS metastases, ECOG PS of 0 or 1, and no persistent toxicities (CTCAE grade >2) from prior cancer therapy. Pts may have received any number of prior regimens. Newly obtained or archival tumor samples will be centrally evaluated using the Lynparza HRR Assay (under development at Foundation Medicine, Inc). Pts will be grouped into 2 cohorts: cohort 1 will include pts with any solid tumor type with a BRCA1 or BRCA2 mutation (excluding breast and ovarian cancers); cohort 2 will include pts whose tumor (any type) is BRCA1 or BRCA2 wild-type and HRRm and/or HRD+ as determined by loss of heterozygosity score. Pts will receive olaparib 300 mg orally BID until documented disease progression, unacceptable toxicity, or study withdrawal. Tumor imaging will be performed at baseline, with response assessments Q8W in the first year and Q12W thereafter, per RECIST v1.1 by BICR or PCWG-modified RECIST v1.1, both modified to follow ≤5 target lesions per organ (10 total). AEs will be graded using NCI CTCAE v4.0. The primary endpoint is ORR; the point estimate and 95% CI calculated using the Clopper-Pearson method will be provided. Summary statistics for key secondary efficacy endpoints of duration of response, OS, and PFS will be provided using the Kaplan-Meier method. Safety endpoints will be summarized. Approximately 370 pts will be enrolled (~84 in cohort 1 [BRCA1 and BRCA2 mutated]; ~174 HRRm and ~112 HRD+ in cohort 2 [BRCA1 and BRCA2 wild-type]). Enrollment is ongoing in 5 countries beginning December 12, 2018.

Citation Format: David Hyman, Andrew Hendifar, Hyun Cheol Chung, Michele Maio, Alexandra Leary, Iben Spanggaard, Joon Rhee, Matt Marton, Menghui Chen, Suba Krishnan, Ronnie Shapira. Olaparib in patients (pts) with previously treated, homologous recombination repair mutation (HRRm) or homologous recombination deficiency (HRD)-positive advanced cancer: Phase II LYNK-002 study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT229.

Application of cell-free DNA for genomic tumor profiling: a feasibility study

Purpose

Access to genomic tumor material is required to select patients for targeted therapies. However, tissue biopsies are not always feasible and therefore circulating cell-free DNA (cfDNA) has emerged as an alternative. Here we investigate the utility of cfDNA for genomic tumor profiling in the phase I setting.

Study design

Peripheral blood was collected from patients with advanced solid cancers eligible for phase I treatment. Patients failing the initial tissue biopsy due to inaccessible lesions or insufficient tumor cellularity (<10%) were included in the study. Genomic profiling of cfDNA including whole exome sequencing (WES) and somatic copy number alterations (SCNAs) analysis (OncoScan).

Results

Plasma cfDNA was pro- and retrospectively profiled from 24 and 20 patients, respectively. The median turnaround time was 29 days (N= 24, range 13-87 days) compared to tissue re-analyses of median 60 days (N= 6, range 29-98). Selected cancer-associated alterations (SCAAs) were identified in 70% (31/44) of patients, predominantly by WES due to the low sensitivity of OncoScan on cfDNA. Primarily, inaccessible cases of prostate and lung cancers could benefit from cfDNA profiling. In contrast, breast cancer patients showed a low level of tumor-specific cfDNA which might be due to cancer type and/or active treatment at the time of plasma collection.

Conclusion

Plasma cfDNA profiling using WES is feasible within a clinically relevant timeframe and represents an alternative to invasive tissue biopsies to identify possible treatment targets. Especially, difficult-to-biopsy cancers can benefit from cfDNA profiling, but tumor tissue remains the gold standard for molecular analyses.

Copenhagen Prospective Personalized Oncology (CoPPO)-Clinical Utility of Using Molecular Profiling to Select Patients to Phase I Trials

PURPOSE

We evaluated the clinical benefit of tumor molecular profiling to select treatment in the phase I setting.

EXPERIMENTAL DESIGN

Patients with advanced solid cancers and exhausted treatment options referred to a phase I unit were included in a prospective, single-center, single-arm open-label study (NCT02290522). Tumor biopsies were obtained for comprehensive genomic analysis including whole-exome sequencing and RNA sequencing. When possible, patients were treated with regimen matched to the genomic profile. Primary endpoint was progression-free survival (PFS).

RESULTS

From May 2013 to January 2017, a total of 591 patients were enrolled, with 500 patients undergoing biopsy. Genomic profiles were obtained in 460 patients and a potential actionable target was identified in 352 (70%) of 500 biopsied patients. A total of 101 patients (20%) received matched treatment based on either gene mutations or RNA expression levels of targets available in early clinical trials or off-label treatment. Objective response according to RECIST1.1 was observed in 15 of 101 patients (0% complete response, 15% partial response), with a median PFS of 12 weeks (95% confidence interval, 9.9-14.4).

CONCLUSIONS

Our study supports the feasibility of genomic profiling to select patients in the phase I setting and suggests that genomic matching can be beneficial for a minor subset of patients with no other treatment options. Randomized studies may validate this assumption.See related commentary by Ratain, p. 1136.

Gene therapy for patients with advanced solid tumors: a phase I study using gene electrotransfer to muscle with the integrin inhibitor plasmid AMEP

BACKGROUND

Gene electrotrotransfer describes the use of electric pulses to transfer DNA to cells. Particularly skeletal muscle has potential for systemic secretion of therapeutic proteins. Gene electrotransfer to muscle using the integrin inhibitor plasmid AMEP (Antiangiogenic MEtargidin Peptide) was investigated in a phase I dose escalation study. Primary objective was safety.

MATERIAL AND METHODS

Patients with metastatic or locally advanced solid tumors, without further standard treatments available, were treated with once-only gene electrotransfer of plasmid AMEP to the femoral muscle. Safety was monitored by adverse events registration, visual analog scale (VAS) after procedure and magnetic resonance imaging (MRI) of treated muscles. Pharmacokinetics of plasmid AMEP in plasma and urine was determined by quantitative polymerase chain reaction. Response was evaluated by positron emission tomography-computed tomography (PET-CT) scans.

RESULTS

Seven patients were enrolled and treated at dose levels from 50 to 250 μg of plasmid AMEP, the study was terminated early due to cessation of plasmid production. Minimal systemic toxicity was observed and only transient mild pain was associated with the delivery of the electric pulses. MRI of the treated muscles revealed discrete intramuscular edema 24 h after treatment. The changes in the muscle tissue resolved within 2 weeks after treatment. Peak concentrations of plasmid AMEP was detected only in plasma within the first 24 hours after injection. Protein AMEP could not be detected, which could be due to the limit of detection. No objective responses were seen.

CONCLUSIONS

Gene electrotransfer of plasmid AMEP was found to be safe and tolerable. No objective responses were observed but other DNA drugs may be tested in the future using this procedure.

Antiangiogenic Metargidin Peptide (AMEP) Gene Therapy in Disseminated Melanoma

Gene delivery by electroporation is an efficient method for transfecting genes into various tissues including tumors. Here we present the treatment protocol used in a phase 1 study on gene electrotransfer of plasmid DNA encoding an antiangiogenic peptide into cutaneous melanoma.

Gene electrotransfer of plasmid antiangiogenic metargidin peptide (AMEP) in disseminated melanoma: safety and efficacy results of a phase I first-in-man study

Antiangiogenic metargidin peptide (AMEP) is a novel anticancer agent exerting antiproliferative and antiangiogenic effects by binding to αvβ3 and α5β1 integrins. Electrotransfer designates the use of electric pulses (electroporation) to transfer plasmid DNA into tissues. This first-in-man phase I study investigated safety and tolerability of intratumoral plasmid AMEP electrotransfer into cutaneous metastatic melanoma. Secondary objectives were efficacy and pharmacokinetics. Five patients with disseminated melanoma without further treatment options were treated at two dose levels (1 and 2 mg DNA). In each patient, two cutaneous lesions were identified (one treated and one control). At day 1 and day 8, plasmid AMEP was injected intratumorally followed by electrotransfer. Patients were monitored weekly until day 29, and at day 64. Local efficacy was assessed at day 29 by direct measurement, and posttreatment biopsies for AMEP mRNA levels were evaluated by reverse transcriptase quantitative polymerase chain reaction. Plasmid copy number in blood and urine was determined by quantitative polymerase chain reaction. Minimal systemic toxicity was observed, including transient fever and transitory increase in C-reactive protein. No related serious adverse events occurred. Plasmid AMEP was detected in plasma but not in urine. AMEP mRNA was found in three of five treated lesions and none of the control lesions. At day 29, all five treated lesions were stable in diameter, whereas four of five control lesions increased more than 20%. No response occurred in distant lesions. This first-in-man study on electrotransfer of plasmid AMEP into cutaneous melanoma shows that the procedure and drug are safe and that local transfection was obtained.

Calcium electrotransfer for termination of transgene expression in muscle

Gene electrotransfer is expanding in clinical use, thus we have searched for an emergency procedure to stop transgene expression in case of serious adverse events. Calcium is cytotoxic at high intracellular levels, so we tested effects of calcium electrotransfer on transgene expression in muscle. A clinical grade calcium solution (20 μl, 168 mM) was injected into transfected mouse or rat tibialis cranialis muscle. Ca(2+) uptake was quantified using calcium 45 ((45)Ca), and voltage and time between injection and pulsation were varied. Extinction of transgene expression was investigated by using both in vivo imaging of infrared fluorescent "Katushka" and erythropoietin evaluated by ELISA and hemoglobin. Histology was performed. Electrotransfer of Katushka and erythropoietin yielded significant expression. Maximal calcium uptake occurred after injection of Ca(2+) before electropulsing using eight high voltage pulses of 1000 V/cm. Using these parameters, in vivo imaging showed that transgene expression significantly decreased 4 hr after Ca(2+) electrotransfer and was eliminated within 24 hr. Similarly, serum erythropoietin was reduced by 46% at 4 hr and to control levels at 2 days. Histological analyses showed muscle damage and subsequent regeneration. Electrotransfer of isotonic CaCl(2) terminates transgenic protein expression in muscles and may be used for contingency elimination of transgene expression.

Self-reported and technician-measured waist circumferences differ in middle-aged men and women

We investigated the agreement between 1) self-reported and technician-measured waist circumference at the level of the umbilicus, 2) circumference measured at the level of the umbilicus and halfway between the lower rib and the iliac crest (the natural waist), and 3) self-reported circumference at the level of the umbilicus and technician-measured circumference at the natural waist. At follow-up in the Danish "Diet, Cancer and Health" study, we recruited 176 men and 240 women for a validation study. Bland-Altman plots were used to evaluate agreement among measurement sites. Multiple regression was used to identify variables explaining the difference between measurements. The participants underestimated their waist circumference; the mean differences were -1.6 cm (95% CI: -2.4 cm, -0.8 cm) in men and -3.0 cm (95% CI: -3.8 cm, -2.3 cm) in women. Limits of agreement were from -11.9 to +8.7 cm among men and -14.9 to +8.9 cm among women. High BMI and large baseline waist circumference were associated with a larger degree of underreporting. Waist circumference measured at the level of the umbilicus was larger than at the natural waist; the mean differences were +0.7 cm (95% CI: +0.4 cm, +1.1 cm) in men and +5.0 cm (95% CI: +4.4 cm, +5.6 cm) in women. The self-reported waist circumference at the level of the umbilicus was correlated with the technician-measured circumference at the natural waist. The circumference at the natural waist was overestimated for women, depending on baseline waist circumference, and slightly underestimated for men, depending on baseline BMI.