Efficacy and Safety of Adagrasib plus Cetuximab in Patients with KRASG12C-Mutated Metastatic Colorectal Cancer

Adagrasib, an irreversible, selective KRASG12C inhibitor, may be an effective treatment in KRASG12C-mutated colorectal cancer, particularly when combined with an anti-EGFR antibody. In this analysis of the KRYSTAL-1 trial, patients with previously treated KRASG12C-mutated unresectable or metastatic colorectal cancer received adagrasib (600 mg twice daily) plus cetuximab. The primary endpoint was objective response rate (ORR) by blinded independent central review. Ninety-four patients received adagrasib plus cetuximab. With a median follow-up of 11.9 months, ORR was 34.0%, disease control rate was 85.1%, and median duration of response was 5.8 months (95% confidence interval [CI], 4.2-7.6). Median progression-free survival was 6.9 months (95% CI, 5.7-7.4) and median overall survival was 15.9 months (95% CI, 11.8-18.8). Treatment-related adverse events (TRAEs) occurred in all patients; grade 3-4 in 27.7% and no grade 5. No TRAEs led to adagrasib discontinuation. Exploratory analyses suggest circulating tumor DNA may identify features of response and acquired resistance.

SIGNIFICANCE

Adagrasib plus cetuximab demonstrates promising clinical activity and tolerable safety in heavily pretreated patients with unresectable or metastatic KRASG12C-mutated colorectal cancer. These data support a potential new standard of care and highlight the significance of testing and identification of KRASG12C mutations in patients with colorectal cancer.

Selective Personalized RadioImmunotherapy for Locally Advanced Non-Small-Cell Lung Cancer Trial (SPRINT)

PURPOSE

Standard therapy for locally advanced non-small-cell lung cancer (LA-NSCLC) is concurrent chemoradiotherapy followed by adjuvant durvalumab. For biomarker-selected patients with LA-NSCLC, we hypothesized that sequential pembrolizumab and risk-adapted radiotherapy, without chemotherapy, would be well-tolerated and effective.

METHODS

Patients with stage III NSCLC or unresectable stage II NSCLC and an Eastern Cooperative Oncology Group performance status of 0-1 were eligible for this trial. Patients with a PD-L1 tumor proportion score (TPS) of ≥50% received three cycles of induction pembrolizumab (200 mg, once every 21 days), followed by a 20-fraction course of risk-adapted thoracic radiotherapy (55 Gy delivered to tumors or lymph nodes with metabolic volume exceeding 20 cc, 48 Gy delivered to smaller lesions), followed by consolidation pembrolizumab to complete a 1-year treatment course. The primary study end point was 1-year progression-free survival (PFS). Secondary end points included response rates after induction pembrolizumab, overall survival (OS), and adverse events.

RESULTS

Twenty-five patients with a PD-L1 TPS of ≥50% were enrolled. The median age was 71, most patients (88%) had stage IIIA or IIIB disease, and the median PD-L1 TPS was 75%. Two patients developed disease progression during induction pembrolizumab, and two patients discontinued pembrolizumab after one infusion because of immune-related adverse events. Using RECIST criteria, 12 patients (48%) exhibited a partial or complete response after induction pembrolizumab. Twenty-four patients (96%) received definitive thoracic radiotherapy. The 1-year PFS rate is 76%, satisfying our efficacy objective. One- and 2-year OS rates are 92% and 76%, respectively. The most common grade 3 adverse events were colitis (n = 2, 8%) and esophagitis (n = 2, 8%), and no higher-grade treatment-related adverse events have occurred.

CONCLUSION

Pembrolizumab and risk-adapted radiotherapy, without chemotherapy, are a promising treatment approach for patients with LA-NSCLC with a PD-L1 TPS of ≥50%.

Amivantamab plus Chemotherapy in NSCLC with EGFR Exon 20 Insertions

BACKGROUND

Amivantamab has been approved for the treatment of patients with advanced non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) exon 20 insertions who have had disease progression during or after platinum-based chemotherapy. Phase 1 data showed the safety and antitumor activity of amivantamab plus carboplatin-pemetrexed (chemotherapy). Additional data on this combination therapy are needed.

METHODS

In this phase 3, international, randomized trial, we assigned in a 1:1 ratio patients with advanced NSCLC with EGFR exon 20 insertions who had not received previous systemic therapy to receive intravenous amivantamab plus chemotherapy (amivantamab-chemotherapy) or chemotherapy alone. The primary outcome was progression-free survival according to blinded independent central review. Patients in the chemotherapy group who had disease progression were allowed to cross over to receive amivantamab monotherapy.

RESULTS

A total of 308 patients underwent randomization (153 to receive amivantamab-chemotherapy and 155 to receive chemotherapy alone). Progression-free survival was significantly longer in the amivantamab-chemotherapy group than in the chemotherapy group (median, 11.4 months and 6.7 months, respectively; hazard ratio for disease progression or death, 0.40; 95% confidence interval [CI], 0.30 to 0.53; P<0.001). At 18 months, progression-free survival was reported in 31% of the patients in the amivantamab-chemotherapy group and in 3% in the chemotherapy group; a complete or partial response at data cutoff was reported in 73% and 47%, respectively (rate ratio, 1.50; 95% CI, 1.32 to 1.68; P<0.001). In the interim overall survival analysis (33% maturity), the hazard ratio for death for amivantamab-chemotherapy as compared with chemotherapy was 0.67 (95% CI, 0.42 to 1.09; P = 0.11). The predominant adverse events associated with amivantamab-chemotherapy were reversible hematologic and EGFR-related toxic effects; 7% of patients discontinued amivantamab owing to adverse reactions.

CONCLUSIONS

The use of amivantamab-chemotherapy resulted in superior efficacy as compared with chemotherapy alone as first-line treatment of patients with advanced NSCLC with EGFR exon 20 insertions. (Funded by Janssen Research and Development; PAPILLON ClinicalTrials.gov number, NCT04538664.).

Amivantamab plus lazertinib in osimertinib-relapsed EGFR-mutant advanced non-small cell lung cancer: a phase 1 trial

Patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) often develop resistance to current standard third-generation EGFR tyrosine kinase inhibitors (TKIs); no targeted treatments are approved in the osimertinib-relapsed setting. In this open-label, dose-escalation and dose-expansion phase 1 trial, the potential for improved anti-tumor activity by combining amivantamab, an EGFR-MET bispecific antibody, with lazertinib, a third-generation EGFR TKI, was evaluated in patients with EGFR-mutant NSCLC whose disease progressed on third-generation TKI monotherapy but were chemotherapy naive (CHRYSALIS cohort E). In the dose-escalation phase, the recommended phase 2 combination dose was established; in the dose-expansion phase, the primary endpoints were safety and overall response rate, and key secondary endpoints included progression-free survival and overall survival. The safety profile of amivantamab and lazertinib was generally consistent with previous experience of each agent alone, with 4% experiencing grade ≥3 events; no new safety signals were identified. In an exploratory cohort of 45 patients who were enrolled without biomarker selection, the primary endpoint of investigator-assessed overall response rate was 36% (95% confidence interval, 22-51). The median duration of response was 9.6 months, and the median progression-free survival was 4.9 months. Next-generation sequencing and immunohistochemistry analyses identified high EGFR and/or MET expression as potential predictive biomarkers of response, which will need to be validated with prospective assessment. ClinicalTrials.gov identifier: NCT02609776 .

Intracranial Efficacy of Adagrasib in Patients From the KRYSTAL-1 Trial With KRASG12C-Mutated Non-Small-Cell Lung Cancer Who Have Untreated CNS Metastases

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Patients with Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutated non-small-cell lung cancer (NSCLC) and untreated CNS metastases have a worse prognosis than similar patients without KRAS mutations. Adagrasib has previously demonstrated CNS penetration preclinically and cerebral spinal fluid penetration clinically. We evaluated adagrasib in patients with KRASG12C-mutated NSCLC and untreated CNS metastases from the KRYSTAL-1 trial (ClinicalTrials.gov identifier: NCT03785249; phase Ib cohort), in which adagrasib 600 mg was administered orally, twice daily. Study outcomes included the safety and clinical activity (intracranial [IC] and systemic) by blinded independent central review. Twenty-five patients with KRASG12C-mutated NSCLC and untreated CNS metastases were enrolled and evaluated (median follow-up, 13.7 months); 19 patients were radiographically evaluable for IC activity. Safety was consistent with previous reports of adagrasib, with grade 3 treatment-related adverse events (TRAEs) in 10 patients (40%) and one grade 4 (4%) and no grade 5 TRAEs. The most common CNS-specific TRAEs included dysgeusia (24%) and dizziness (20%). Adagrasib demonstrated an IC objective response rate of 42%, disease control rate of 90%, progression-free survival of 5.4 months, and median overall survival of 11.4 months. Adagrasib is the first KRASG12C inhibitor to prospectively demonstrate IC activity in patients with KRASG12C-mutated NSCLC and untreated CNS metastases, supporting further investigation in this population.

Adagrasib in Advanced Solid Tumors Harboring a KRASG12C Mutation

PURPOSE

Adagrasib, a KRASG12C inhibitor, has demonstrated clinical activity in patients with KRASG12C-mutated non-small-cell lung cancer (NSCLC) and colorectal cancer (CRC). KRASG12C mutations occur rarely in other solid tumor types. We report evaluation of the clinical activity and safety of adagrasib in patients with other solid tumors harboring a KRASG12C mutation.

METHODS

In this phase II cohort of the KRYSTAL-1 study (ClinicalTrials.gov identifier: NCT03785249; phase Ib cohort), we evaluated adagrasib (600 mg orally twice daily) in patients with KRASG12C-mutated advanced solid tumors (excluding NSCLC and CRC). The primary end point was objective response rate. Secondary end points included duration of response, progression-free survival (PFS), overall survival, and safety.

RESULTS

As of October 1, 2022, 64 patients with KRASG12C-mutated solid tumors were enrolled and 63 patients treated (median follow-up, 16.8 months). The median number of prior lines of systemic therapy was 2. Among 57 patients with measurable disease at baseline, objective responses were observed in 20 (35.1%) patients (all partial responses), including 7/21 (33.3%) responses in pancreatic and 5/12 (41.7%) in biliary tract cancers. The median duration of response was 5.3 months (95% CI, 2.8 to 7.3) and median PFS was 7.4 months (95% CI, 5.3 to 8.6). Treatment-related adverse events (TRAEs) of any grade were observed in 96.8% of patients and grade 3-4 in 27.0%; there were no grade 5 TRAEs. TRAEs did not lead to treatment discontinuation in any patients.

CONCLUSION

Adagrasib demonstrates encouraging clinical activity and is well tolerated in this rare cohort of pretreated patients with KRASG12C-mutated solid tumors.

Clinical and Genomic Features of Response and Toxicity to Sotorasib in a Real-World Cohort of Patients With Advanced KRAS G12C-Mutant Non-Small Cell Lung Cancer

PURPOSE

With the recent approval of the KRAS G12C inhibitor sotorasib for patients with advanced KRAS G12C-mutant non-small cell lung cancer (NSCLC), there is a new need to identify factors associated with activity and toxicity among patients treated in routine practice.

MATERIALS AND METHODS

We conducted a multicenter retrospective study of patients treated with sotorasib outside of clinical trials to identify factors associated with real-world progression free survival (rwPFS), overall survival (OS), and toxicity.

RESULTS

Among 105 patients with advanced KRAS G12C-mutant NSCLC treated with sotorasib, treatment led to a 5.3-month median rwPFS, 12.6-month median OS, and 28% real-world response rate. KEAP1 comutations were associated with shorter rwPFS and OS (rwPFS hazard ratio [HR], 3.19; P = .004; OS HR, 4.10; P = .003); no significant differences in rwPFS or OS were observed across TP53 (rwPFS HR, 1.10; P = .731; OS HR, 1.19; P = .631) or STK11 (rwPFS HR, 1.66; P = .098; OS HR, 1.73; P = .168) comutation status. Notably, almost all patients who developed grade 3 or higher treatment-related adverse events (G3+ TRAEs) had previously been treated with anti-PD-(L)1 therapy. Among these patients, anti-PD-(L)1 therapy exposure within 12 weeks of sotorasib was strongly associated with G3+ TRAEs (P < .001) and TRAE-related sotorasib discontinuation (P = .014). Twenty-eight percent of patients with recent anti-PD-(L)1 therapy exposure experienced G3+ TRAEs, most commonly hepatotoxicity.

CONCLUSION

Among patients treated with sotorasib in routine practice, KEAP1 comutations were associated with resistance and recent anti-PD-(L)1 therapy exposure was associated with toxicity. These observations may help guide use of sotorasib in the clinic and may help inform the next generation of KRAS G12C-targeted clinical trials.

Management of infusion-related reactions (IRRs) in patients receiving amivantamab in the CHRYSALIS study

BACKGROUND

Amivantamab, a fully humanized EGFR-MET bispecific antibody, has antitumor activity in diverse EGFR- and MET-driven non-small cell lung cancer (NSCLC) and a safety profile consistent with associated on-target activities. Infusion-related reaction(s) (IRR[s]) are reported commonly with amivantamab. We review IRR and subsequent management in amivantamab-treated patients.

METHODS

Patients treated with the approved dose of intravenous amivantamab (1050 mg, <80 kg; 1400 mg, ≥80 kg) in CHRYSALIS-an ongoing, phase 1 study in advanced EGFR-mutated NSCLC-were included in this analysis. IRR mitigations included split first dose (350 mg, day 1 [D1]; remainder, D2), reduced initial infusion rates with proactive infusion interruption, and steroid premedication before initial dose. For all doses, pre-infusion antihistamines and antipyretics were required. Steroids were optional after the initial dose.

RESULTS

As of 3/30/2021, 380 patients received amivantamab. IRRs were reported in 256 (67%) patients. Signs/symptoms of IRR included chills, dyspnea, flushing, nausea, chest discomfort, and vomiting. Most of the 279 IRRs were grade 1 or 2; grade 3 and 4 IRR occurred in 7 and 1 patients, respectively. Most (90%) IRRs occurred on cycle 1, D1 (C1D1); median time-to-first-IRR onset during C1D1 was 60 min; and first-infusion IRRs did not compromise subsequent infusions. Per protocol, IRR was mitigated on C1D1 with holding of infusion (56% [214/380]), reinitiating at reduced rate (53% [202/380]), and aborting infusion (14% [53/380]). C1D2 infusions were completed in 85% (45/53) of patients who had C1D1 infusions aborted. Four patients (1% [4/380]) discontinued treatment due to IRR. In studies aimed at elucidating the underlying mechanism(s) of IRR, no pattern was observed between patients with versus without IRR.

CONCLUSION

IRRs with amivantamab were predominantly low grade and limited to first infusion, and rarely occurred with subsequent dosing. Close monitoring for IRR with the initial amivantamab dose and early intervention at first IRR signs/symptoms should be part of routine amivantamab administration.

Activity of Adagrasib (MRTX849) in Brain Metastases: Preclinical Models and Clinical Data from Patients with KRASG12C-Mutant Non-Small Cell Lung Cancer

PURPOSE

Patients with KRAS-mutant non-small cell lung cancer (NSCLC) with brain metastases (BM) have a poor prognosis. Adagrasib (MRTX849), a potent oral small-molecule KRASG12C inhibitor, irreversibly and selectively binds KRASG12C, locking it in its inactive state. Adagrasib has been optimized for favorable pharmacokinetic properties, including long half-life (∼24 hours), extensive tissue distribution, dose-dependent pharmacokinetics, and central nervous system penetration; however, BM-specific antitumor activity of KRASG12C inhibitors remains to be fully characterized.

EXPERIMENTAL DESIGN

A retrospective database query identified patients with KRAS-mutant NSCLC to understand their propensity to develop BM. Preclinical studies assessed physiochemical and pharmacokinetic properties of adagrasib. Mice bearing intracranial KRASG12C-mutant NSCLC xenografts (LU99-Luc/H23-Luc/LU65-Luc) were treated with clinically relevant adagrasib doses, and levels of adagrasib in plasma, cerebrospinal fluid (CSF), and brain were determined along with antitumor activity. Preliminary clinical data were collected from 2 patients with NSCLC with untreated BM who had received adagrasib 600 mg twice daily in the phase Ib cohort of the KRYSTAL-1 trial; CSF was collected, adagrasib concentrations measured, and antitumor activity in BM evaluated.

RESULTS

Patients with KRAS-mutant NSCLC demonstrated high propensity to develop BM (≥40%). Adagrasib penetrated into CSF and demonstrated tumor regression and extended survival in multiple preclinical BM models. In 2 patients with NSCLC and untreated BM, CSF concentrations of adagrasib measured above the target cellular IC50. Both patients demonstrated corresponding BM regression, supporting potential clinical activity of adagrasib in the brain.

CONCLUSIONS

These data support further development of adagrasib in patients with KRASG12C-mutant NSCLC with untreated BM. See related commentary by Kommalapati and Mansfield, p. 3179.

The incidence and predictors of new brain metastases in patients with non-small cell lung cancer following discontinuation of systemic therapy

OBJECTIVE

Patients with non-small cell lung cancer (NSCLC) metastatic to the brain are living longer. The risk of new brain metastases when these patients stop systemic therapy is unknown. The authors hypothesized that the risk of new brain metastases remains constant for as long as patients are off systemic therapy.

METHODS

A prospectively collected registry of patients undergoing radiosurgery for brain metastases was analyzed. Of 606 patients with NSCLC, 63 met the inclusion criteria of discontinuing systemic therapy for at least 90 days and undergoing active surveillance. The risk factors for the development of new tumors were determined using Cox proportional hazards and recurrent events models.

RESULTS

The median duration to new brain metastases off systemic therapy was 16.0 months. The probability of developing an additional new tumor at 6, 12, and 18 months was 26%, 40%, and 53%, respectively. There were no additional new tumors 22 months after stopping therapy. Patients who discontinued therapy due to intolerance or progression of the disease and those with mutations in RAS or receptor tyrosine kinase (RTK) pathways (e.g., KRAS, EGFR) were more likely to develop new tumors (hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.33-3.81, p = 2.5 × 10-3; HR 2.51, 95% CI 1.45-4.34, p = 9.8 × 10-4, respectively).

CONCLUSIONS

The rate of new brain metastases from NSCLC in patients off systemic therapy decreases over time and is uncommon 2 years after cessation of cancer therapy. Patients who stop therapy due to toxicity or who have RAS or RTK pathway mutations have a higher rate of new metastases and should be followed more closely.

Adagrasib in Non-Small-Cell Lung Cancer Harboring a KRASG12C Mutation

BACKGROUND

Adagrasib, a KRAS^G12C inhibitor, irreversibly and selectively binds KRAS^G12C, locking it in its inactive state. Adagrasib showed clinical activity and had an acceptable adverse-event profile in the phase 1-1b part of the KRYSTAL-1 phase 1-2 study.

METHODS

In a registrational phase 2 cohort, we evaluated adagrasib (600 mg orally twice daily) in patients with KRAS^G12C -mutated non-small-cell lung cancer (NSCLC) previously treated with platinum-based chemotherapy and anti-programmed death 1 or programmed death ligand 1 therapy. The primary end point was objective response assessed by blinded independent central review. Secondary end points included the duration of response, progression-free survival, overall survival, and safety.

RESULTS

As of October 15, 2021, a total of 116 patients with KRAS^G12C -mutated NSCLC had been treated (median follow-up, 12.9 months); 98.3% had previously received both chemotherapy and immunotherapy. Of 112 patients with measurable disease at baseline, 48 (42.9%) had a confirmed objective response. The median duration of response was 8.5 months (95% confidence interval [CI], 6.2 to 13.8), and the median progression-free survival was 6.5 months (95% CI, 4.7 to 8.4). As of January 15, 2022 (median follow-up, 15.6 months), the median overall survival was 12.6 months (95% CI, 9.2 to 19.2). Among 33 patients with previously treated, stable central nervous system metastases, the intracranial confirmed objective response rate was 33.3% (95% CI, 18.0 to 51.8). Treatment-related adverse events occurred in 97.4% of the patients - grade 1 or 2 in 52.6% and grade 3 or higher in 44.8% (including two grade 5 events) - and resulted in drug discontinuation in 6.9% of patients.

CONCLUSIONS

In patients with previously treated KRAS^G12C -mutated NSCLC, adagrasib showed clinical efficacy without new safety signals. (Funded by Mirati Therapeutics; ClinicalTrials.gov number, NCT03785249.).

Activity of adagrasib (MRTX849) in patients with KRASG12C-mutated NSCLC and active, untreated CNS metastases in the KRYSTAL-1 trial

LBA9009

Background: CNS metastases (mets) occur in 27–42% of NSCLC harboring KRASG12C mutations and are associated with poor prognosis. Adagrasib (ada), an investigational agent, is a KRASG12C inhibitor that irreversibly and selectively binds KRASG12C, locking it in its inactive state, and is optimized for favorable PK properties, including a long half-life (̃24 h) and dose-dependent PK. Ada has demonstrated dose-dependent CNS penetration and intracranial (IC) tumor regression in preclinical models of CNS mets. Methods: KRYSTAL-1 (NCT03785249) is a multicohort Phase 1/2 study evaluating ada as monotherapy or in combination with selected agents in patients (pts) with advanced solid tumors harboring a KRASG12C mutation. In a Phase 1b cohort, pts with KRASG12C-mutant NSCLC and active, untreated CNS mets were treated with ada 600 mg BID. The objectives for this Phase 1b cohort were to evaluate safety and clinical activity, including systemic and IC objective response rate (ORR) by blinded independent central review (BICR), duration of response (DOR), progression-free survival (PFS), and overall survival (OS). Systemic responses were assessed by RECIST 1.1; IC responses were assessed by modified RANO criteria and IC RECIST. Cerebrospinal fluid (CSF) was collected when feasible and was used to measure ada concentrations for optional evaluation. Results: As of 31 December 2021, 25 pts with NSCLC were enrolled and treated. Median follow-up was 6.6 months at the cutoff date. Median age was 66 years, 52% were female, 28%/72% had ECOG PS 0/1, and median lines of prior systemic therapy was one (range 0–4+). IC ORR per modified RANO criteria by BICR was 31.6% (6/19; 3 CRs, 2 PRs, 1 unconfirmed PR); IC disease control rate (DCR) was 84.2% (16/19, including 10 SDs). Median IC DOR was not reached (95% CI 4.1–NE); median IC PFS was 4.2 months (95% CI 3.8–NE). CSF samples were obtained for two pts for whom regression of CNS mets was observed and ada CSF concentrations exceeded the CNS penetrance partition coefficients observed for other therapies with demonstrated CNS penetration and CNS antitumor activity (Kp,uu 0.47). Systemic ORR by BICR was 35.0% (7/20), DCR was 80.0% (16/20) and median DOR was 9.6 months (95% CI 2.7–9.6); median PFS was 5.6 months (95% CI 3.8–11.0). For all pts enrolled, OS was immature, and the median had not been reached at the time of analysis. Safety was consistent with that previously reported with ada; any grade TRAEs occurred in 96% of pts, grade 3 TRAEs in 36%, and there were no grade 4/5 TRAEs. Further data describing IC activity assessed by IC RECIST will be presented. Conclusions: Ada was well tolerated, and these preliminary data demonstrate CNS penetration and encouraging IC activity in pretreated pts with NSCLC harboring a KRASG12C mutation and active, untreated CNS mets. These are the first clinical data demonstrating CNS-specific activity of a KRASG12C inhibitor in this population. Clinical trial information: NCT03785249.

A phase 1/2 study of REGN5093-M114, a METxMET antibody-drug conjugate, in patients with mesenchymal epithelial transition factor (MET)-overexpressing NSCLC

TPS8593

Background: MET, also called hepatocyte growth factor receptor (HGFR), is a high-affinity transmembrane protein receptor for HGF. MET is overexpressed in various malignancies, including non-small cell lung cancer (NSCLC). MET overexpression can accompany MET exon 14 alteration or de novo/acquired MET amplification. REGN5093-M114 is an antibody drug conjugate composed of a novel linker-payload (M114, carrying the maytansine derivative M24, a potent inhibitor of microtubule assembly) covalently bound to lysine residues on a MET-targeting human IgG4p bispecific antibody, REGN5093. In preclinical models of MET overexpressing cancers, REGN5093-M114 demonstrated significant dose-dependent antitumor activity. Methods: This is an open label, phase 1/2, first-in-human, multicenter dose-escalation study with cohort expansion evaluating REGN5093-M114 in patients with MET-overexpressing NSCLC (NCT04982224). Patients must have advanced stage NSCLC for which there are no approved therapies available expected to confer clinical benefit, with tumor overexpressing MET (≥75% tumor cell staining at 2+) as centrally confirmed by immunohistochemistry. For the expansion phase, patients must have at least one lesion that is measurable by RECIST 1.1. REGN5093-M114 will be administered intravenously once every 3 weeks over 30 minutes until disease progression, intolerable adverse events, withdrawal of consent, or study withdrawal. The primary objectives in dose escalation are to evaluate safety, tolerability, PK, and maximum tolerated dose and/or recommended phase 2 dosing regimen of REGN5093-M114. PKs will include the assessment of REGN5093-M114, total antibody, and payload M24 concentrations. The primary objective in dose expansion is to assess preliminary anti-tumor activity of REGN5093-M114 in MET-overexpressing NSCLC as measured by the objective response rate. The secondary objectives of both phases of the study include an evaluation of treatment durability, and the immunogenicity of REGN5093-M114. This study is currently open to enrollment. Clinical trial information: NCT04982224.

Examination of speakership gender disparity at an international oncology conference

11002

Background: Gender disparity is an important issue in medicine, as women occupy a minority of academic leadership positions despite increased representation in the physician workforce. One important aspect is the gender gap of speakers at academic meetings, which limits opportunities for career advancement and mentorship. This underrepresentation of women is largely anecdotal in oncology. We hypothesized that original research is less frequently presented by women at the annual ASCO meeting. We sought to examine presentation patterns from recently featured ASCO speakers, categorized by presentation type and gender. Methods: We conducted a retrospective, observational review of data from the 2018-2021 ASCO annual meetings. Mixed-gender coders extracted data from the ASCO Annual Meeting library and institutional public websites. Speaker-identified gender was unavailable; binary gender was determined by presenter name, pronouns, and video files. For original research, we collected data on last authors as well as these roles are also considered meritorious. Cochran–Mantel–Haenszel tests were used to investigate the association of gender and roles adjusted for each stratification variable individually. Common odds ratios (ORs) were estimated for each association. Breslow-Day Tests were used to test the homogeneity of these ORs among the different levels of each stratification variable. No adjustments for multiple testing were used. Results: We reviewed 4267 unique presentations, including those which highlighted original research (Poster Discussion, Oral Abstract, Clinical Science Symposium, Plenary) vs. education (Case-Based Panel, Education Sessions, Highlights of the Day). For original research, women were significantly more likely to have an ASCO-appointed role (discussant, speaker, or chair) than a first or last author role (48% vs. 32.7% of presentations, p < 0.0001), even after adjusting for conference year (OR 0.53, 95% CI: 0.45-0.61), session type (0.52, 0.45-0.61), degree (0.50, 0.43-0.58), academic rank (0.55, 0.47-0.64), and geographic region (0.58, 0.50-0.68). There was no difference between in-person and virtual conferences (p = 0.584). For education sessions, women comprised 46.1% (n = 626), nearly half, of these speaking roles (all ASCO-appointed) compared with men. 38% of the data was independently re-reviewed to confirm accuracy; 96.4% concordance was observed in presenter gender. Conclusions: Women are less likely to present highlighted original research and are more likely to have an appointed educational role at ASCO annual meetings. This likely reflects broader gender disparity within academia. Future analyses could be improved by examining speaker-identified gender. As high-profile original research can elevate careers, examining factors contributing to this observed disparity may reveal important approaches to address gender leadership gaps in oncology.

KRYSTAL-1: Activity and safety of adagrasib (MRTX849) in patients with advanced/metastatic non–small cell lung cancer (NSCLC) harboring a KRASG12C mutation

9002

Background: KRAS is a key mediator of the RAS/MAPK signaling cascade that promotes cellular growth and proliferation. KRASG12C mutation occurs in ̃14% of NSCLC. Adagrasib, an investigational agent, is a KRASG12C inhibitor that irreversibly and selectively binds KRASG12C, locking it in its inactive state. Adagrasib is optimized for favorable pharmacokinetic (PK) properties, including long half-life (̃24 h), dose-dependent PK, and central nervous system penetration; it has demonstrated objective response and favorable tolerability in the Phase 1/1b setting. Methods: KRYSTAL-1 (NCT03785249) is a multicohort Phase 1/2 study evaluating adagrasib as monotherapy or in combination regimens in patients with advanced solid tumors harboring a KRASG12C mutation. Here we report the first disclosure from all patients enrolled in Cohort A, a Phase 2 cohort with registrational intent, evaluating adagrasib given 600 mg orally BID in patients with NSCLC previously treated with platinum-based chemotherapy and anti-PD-1/L1 therapy. Study objectives include evaluating efficacy (objective response rate [ORR], duration of response [DOR], progression-free survival [PFS], overall survival [OS]), safety, PK, and exploratory correlative analyses. Objective tumor response was assessed per RECIST v1.1 by blinded independent central review (BICR). Results: As of the 15 October 2021 data cutoff, 116 patients with NSCLC harboring a KRASG12C mutation were enrolled and treated, with a median follow-up of 12.5 months. Baseline characteristics include median age 64 years, 65% female, and 15.5%/83.6% with ECOG PS 0/1; 98.3% of patients received adagrasib following prior treatment with immunotherapy and chemotherapy, with a median of 2 prior systemic therapies. The ORR (by BICR) was 42.9% (48/112) and the disease control rate was 79.5% (89/112); 31 patients remain on treatment. Median DOR was 8.5 months (95% CI 6.2–13.8), median PFS was 6.5 months (95% CI 4.7–8.4), median OS was 12.6 months (95% CI 9.2–NE). Treatment-related AEs (TRAEs) of any grade occurred in 97.4% of patients, grade ≥3 TRAEs in 45.7%, 2 grade 5 TRAEs, and 8 (6.9%) TRAEs led to discontinuation. The most commonly reported (≥25%) TRAEs (any grade) were diarrhea (62.9%), nausea (62.1%), vomiting (47.4%), fatigue (40.5%), ALT/AST increased (27.6%/25%), blood creatinine increased (25.9%); the most commonly reported (≥5%) TRAEs (grade 3/4) were lipase increased (6%) and anemia (5.2%). Additional subgroup analyses will be presented, including selected demographics, molecular markers and sites of metastases. Conclusions: Adagrasib is well tolerated and demonstrates promising efficacy in pretreated patients with NSCLC harboring a KRASG12C mutation. A Phase 3 trial evaluating adagrasib monotherapy versus docetaxel in previously treated patients with KRASG12C-mutant NSCLC is ongoing (NCT04685135). Clinical trial information: NCT03785249.

The Selective Personalized Radio-immunotherapy for Locally Advanced NSCLC Trial (SPRINT): Initial results

8510

Background: Standard therapy for unresectable locally advanced non-small cell lung cancer (LA-NSCLC) is concurrent chemoradiotherapy followed by adjuvant durvalumab. We performed a prospective trial testing sequential pembrolizumab and risk-adapted radiotherapy without chemotherapy for biomarker-selected LA-NSCLC patients. Methods: Patients with stage III NSCLC or unresectable stage II NSCLC, ECOG performance status 0-1, and no contraindications to protocol-specified therapy were eligible for this trial. Subjects with PD-L1 tumor proportion score (TPS) ≥ 50% underwent baseline FDG-PET/CT, received three cycles of induction pembrolizumab (200 mg, every 21 days), underwent restaging FDG-PET/CT, received risk-adapted thoracic radiotherapy (55 Gy delivered to tumors or lymph nodes with metabolic tumor volume exceeding 20 cc and 48 Gy delivered to smaller lesions, all in 20 daily fractions), and then received up to 13 cycles of additional pembrolizumab. The primary study endpoint was one-year progression-free survival (PFS). Here we report response rates following induction pembrolizumab, PFS and overall survival (OS) rates, and adverse event rates (CTCAE v. 4.03). Results: Twenty-five subjects with PD-L1 TPS ≥ 50% from three institutions were enrolled between August 2018 and November 2021. Median age was 71 (interquartile range [IQR] 62 to 77). One subject had stage II disease, 13 had stage IIIA disease, nine had stage IIIB disease, and two had stage IIIC disease. Median PD-L1 TPS was 75% (IQR 60 to 80%). Two subjects (8%) developed disease progression during induction pembrolizumab, and two subjects discontinued pembrolizumab after one infusion due to immune-related adverse events. Using RECIST 1.1 criteria, 12 subjects (48%) exhibited a partial (n = 11) or complete (n = 1) response following induction pembrolizumab on CT. Using PERCIST criteria, 12 subjects (48%) exhibited a partial response following induction pembrolizumab on PET. Four subjects had responses on PET but not on CT, and four had responses on CT but not on PET. With a median follow-up duration of 13 months, the actuarial 1-year PFS rate is 74%, and the actuarial 1-year OS rate is 95%. Grade 3 adverse events have been limited to single cases of anemia, arthritis, diarrhea, esophagitis, and pneumonitis, and no grade 4-5 adverse events have occurred. Exploratory analyses suggest that response to induction pembrolizumab on PET predicts efficacy of this treatment approach, with a 1-year PFS rate of 100% for responders, compared to 61% for non-responders (logrank p = 0.007). Conclusions: Treatment with pembrolizumab and risk-adapted radiotherapy is a promising treatment approach for LA-NSCLC patients with PD-L1 TPS ≥ 50%. Response on PET following induction pembrolizumab may be useful for identifying patients who can be treated successfully without chemotherapy. Clinical trial information: NCT03523702.

First-in-Human Phase I/IB Dose-Finding Study of Adagrasib (MRTX849) in Patients With Advanced KRASG12C Solid Tumors (KRYSTAL-1)

Adagrasib (MRTX849) is an oral, highly selective, small-molecule, covalent inhibitor of KRAS^G12C. We report results from a phase I/IB study of adagrasib in non–small-cell lung cancer, colorectal cancer, and other solid tumors harboring the KRAS^G12C mutation.

KRYSTAL-1: Updated activity and safety of adagrasib (MRTX849) in patients (Pts) with unresectable or metastatic pancreatic cancer (PDAC) and other gastrointestinal (GI) tumors harboring a KRASG12C mutation

519

Background: KRAS, the most frequently mutated oncogene in cancer, is a key mediator of the RAS/MAPK signaling cascade that promotes cellular growth and proliferation. KRAS mutations occur in approximately 90% of pancreatic cancer, and approximately 2% of these are KRASG12C mutations. Adagrasib, an investigational agent, is a KRASG12C inhibitor that irreversibly and selectively binds KRASG12C, locking it in its inactive state; adagrasib has been optimized for favorable pharmacokinetic (PK) properties, including long half-life (̃24 h), extensive tissue distribution, dose-dependent PK, as well as CNS penetration. Methods: KRYSTAL-1 (NCT03785249) is a multicohort Phase 1/2 study evaluating adagrasib as monotherapy or in combinations in pts with advanced solid tumors harboring a KRASG12C mutation. Here we report preliminary data from pts enrolled in a Phase 2 cohort evaluating single-agent adagrasib administered orally at 600 mg BID in previously treated pts with unresectable or metastatic solid tumors (excluding NSCLC and CRC), including pancreatic and other GI cancers. Study endpoints include clinical activity, safety, and PK. Results: The data cutoff was 10 September 2021. A total of 42 pts were enrolled in this cohort (median age 63.5 years, range 21–89; 52% female; 71% white; 29%/71% ECOG PS 0/1; median 2 prior lines of therapy, range 1–7; median follow-up 6.3 months), of whom 30 pts had KRASG12C-mutant GI tumors (12 PDAC, 8 biliary tract, 5 appendiceal, 2 gastro-esophageal junction, 2 small bowel, and 1 esophageal). In a preliminary analysis, 27 pts with GI tumors were evaluable for clinical activity; partial responses (PRs) were seen in 41% (11/27, including 3 unconfirmed PRs); the disease control rate (DCR) was 100% (27/27). Of the 12 pts with PDAC (median 3 prior lines of therapy; median follow-up 8.1 months), 10 were evaluable for clinical activity; PRs were seen in 50% (5/10, including 1 unconfirmed PR); the DCR was 100% (10/10). Median progression-free survival (PFS) was 6.6 months (95% CI 1.0–9.7), and treatment was ongoing in 50% of pts with PDAC. Among the 17 evaluable pts with other GI tumors, 6 achieved PR (35%; 2 unconfirmed) with a DCR of 100% (17/17); 11 pts were still receiving treatment. In the overall cohort, treatment-related adverse events of any grade occurred in 91% (38/42), the most frequent being nausea (48%), diarrhea (43%), vomiting (43%), and fatigue (29%); grade 3/4 events occurred in 21% of pts, with no grade 5 events. Conclusions: Adagrasib monotherapy is well tolerated and demonstrates encouraging clinical activity in pretreated pts with PDAC and other GI tumors harboring a KRASG12C mutation. Further exploration of adagrasib is ongoing in this pt population (NCT03785249). Clinical trial information: NCT03785249.

Hitting the Right Spot: Advances in the Treatment of NSCLC With Uncommon EGFR Mutations

An understanding of the biology of uncommon epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) is evolving. These mutations are important for the selection of targeted therapy and the development of resistance. The advent of genomic profiling has led to guideline-recommended molecular testing to identify patients with NSCLC who carry uncommon EGFR mutations to aid in the selection of appropriate targeted therapy. This article discusses the efficacy and safety of current and emerging targeted therapies for the treatment of uncommon EGFR mutations in NSCLC to aid in developing patient-specific treatment plans.

Presentation, Diagnosis and Management of Innominate Artery Thromboembolism

PURPOSE

Acute thromboembolic disease of the innominate artery (IA) poses a unique set of therapeutic challenges, owing to its contribution to both the cerebral and upper extremity circulation, and risks of distal embolization via the carotid and subclavian arteries, respectively. Herein, we present a 74-year-old female who presents with acute IA thrombus treated successfully with right axillary and common carotid exposure and aspiration catheter-directed mechanical thrombectomy (CDT). Furthermore, an emerging use of CDT and its application in acute thromboembolism are outlined.

CASE REPORT

A 74-year-old female with history of right lung transplant for pulmonary fibrosis with severe pulmonary hypertension, and stage IIIA left lung adenocarcinoma status post left lower lobectomy undergoing adjuvant chemotherapy presented with acute IA thrombus and right-sided stroke. She was treated successfully with right axillary and common carotid exposure and aspiration CDT. Computed tomography angiography performed 1 month postoperatively confirmed patent IA with no evidence of residual or recurrent thrombus.

CONCLUSION

There are currently no standard guidelines on the management of acute IA thromboembolism, with mostly individual cases reported in the literature describing this rare entity. Nevertheless, this unique clinical entity mandates expeditious diagnostic and therapeutic approaches in order to avoid permanent neurologic deficits from distal embolization. Our case demonstrates that aspiration CDT may be an effective treatment modality for patients with acute IA thrombus.

Amivantamab in EGFR Exon 20 Insertion-Mutated Non-Small-Cell Lung Cancer Progressing on Platinum Chemotherapy: Initial Results From the CHRYSALIS Phase I Study

PURPOSE

Non–small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) exon 20 insertion (Exon20ins) mutations exhibits inherent resistance to approved tyrosine kinase inhibitors. Amivantamab, an EGFR-MET bispecific antibody with immune cell–directing activity, binds to each receptor's extracellular domain, bypassing resistance at the tyrosine kinase inhibitor binding site.

METHODS

CHRYSALIS is a phase I, open-label, dose-escalation, and dose-expansion study, which included a population with EGFR Exon20ins NSCLC. The primary end points were dose-limiting toxicity and overall response rate. We report findings from the postplatinum EGFR Exon20ins NSCLC population treated at the recommended phase II dose of 1,050 mg amivantamab (1,400 mg, ≥ 80 kg) given once weekly for the first 4 weeks and then once every 2 weeks starting at week 5.

RESULTS

In the efficacy population (n = 81), the median age was 62 years (range, 42-84 years); 40 patients (49%) were Asian, and the median number of previous lines of therapy was two (range, 1-7). The overall response rate was 40% (95% CI, 29 to 51), including three complete responses, with a median duration of response of 11.1 months (95% CI, 6.9 to not reached). The median progression-free survival was 8.3 months (95% CI, 6.5 to 10.9). In the safety population (n = 114), the most common adverse events were rash in 98 patients (86%), infusion-related reactions in 75 (66%), and paronychia in 51 (45%). The most common grade 3-4 adverse events were hypokalemia in six patients (5%) and rash, pulmonary embolism, diarrhea, and neutropenia in four (4%) each. Treatment-related dose reductions and discontinuations were reported in 13% and 4% of patients, respectively.

CONCLUSION

Amivantamab, via its novel mechanism of action, yielded robust and durable responses with tolerable safety in patients with EGFR Exon20ins mutations after progression on platinum-based chemotherapy.

Comprehensive Molecular and Clinicopathologic Analysis of 200 Pulmonary Invasive Mucinous Adenocarcinomas Identifies Distinct Characteristics of Molecular Subtypes

PURPOSE

Invasive mucinous adenocarcinoma (IMA) is a unique subtype of lung adenocarcinoma, characterized genomically by frequent KRAS mutations or specific gene fusions, most commonly involving NRG1. Comprehensive analysis of a large series of IMAs using broad DNA- and RNA-sequencing methods is still lacking, and it remains unclear whether molecular subtypes of IMA differ clinicopathologically.

EXPERIMENTAL DESIGN

A total of 200 IMAs were analyzed by 410-gene DNA next-generation sequencing (MSK-IMPACT; n = 136) or hotspot 8-oncogene genotyping (n = 64). Driver-negative cases were further analyzed by 62-gene RNA sequencing (MSK-Fusion) and those lacking fusions were further tested by whole-exome sequencing and whole-transcriptome sequencing (WTS).

RESULTS

Combined MSK-IMPACT and MSK-Fusion testing identified mutually exclusive driver alterations in 96% of IMAs, including KRAS mutations (76%), NRG1 fusions (7%), ERBB2 alterations (6%), and other less common events. In addition, WTS identified a novel NRG2 fusion (F11R-NRG2). Overall, targetable gene fusions were identified in 51% of KRAS wild-type IMAs, leading to durable responses to targeted therapy in some patients. Compared with KRAS-mutant IMAs, NRG1-rearranged tumors exhibited several more aggressive characteristics, including worse recurrence-free survival (P < 0.0001).

CONCLUSIONS

This is the largest molecular study of IMAs to date, where we demonstrate the presence of a major oncogenic driver in nearly all cases. This study is the first to document more aggressive characteristics of NRG1-rearranged IMAs, ERBB2 as the third most common alteration, and a novel NRG2 fusion in these tumors. Comprehensive molecular testing of KRAS wild-type IMAs that includes fusion testing is essential, given the high prevalence of alterations with established and investigational targeted therapies in this subset.

The Common Thread: A Case of Synchronous Lung Cancers and a Germline CHEK2 Mutation

Patients with one form of cancer are at increased risk for another, and this is true for lung cancer, where synchronous primary lung cancers are an increasing multifaceted challenge.^1,2 Here, we present the case of a middle age woman who was found to have bilateral lung masses. Biopsy and subsequent testing revealed unique synchronous lung adenocarcinomas, each with unique genetic signatures. Despite having two unique tumors, she was found to have CHEK2 mutations in both tumors and in germline testing. Because of this extensive testing that showed unique tumors, she was ultimately diagnosed with stage IIIb and IA2 lung cancers, and this changed her treatment options. Consideration of unique primary tumors leads to thorough diagnostics, which changed this patient's diagnosis, prognosis, and treatment. We hope this case raises awareness for multiple primary tumors, as well as CHEK2 as an important oncogene.

Phase II two-arm study of tepotinib plus osimertinib in patients with EGFR-mutant NSCLC and acquired resistance to first-line osimertinib due to MET amplification: INSIGHT 2

TPS9136

Background: METamp is a mechanism of acquired resistance to EGFR tyrosine kinase inhibitors (TKIs). METamp occurs in ̃30% of patients who progress on EGFR TKI therapy as measured using fluorescence in situ hybridization (FISH). There is an unmet need for targeted treatment options in these patients. Combination treatment with a MET TKI may overcome MET-related osimertinib resistance. Tepotinib is an oral, once daily (QD), highly selective, potent MET TKI. In the INSIGHT study (NCT01982955), the combination of tepotinib and the EGFR TKI gefitinib improved outcomes in patients with EGFR-mutant METamp NSCLC and EGFR TKI resistance compared to chemotherapy (INSIGHT). Median progression-free survival (PFS) was 16.6 vs 4.2 months (hazard ratio [HR] = 0.13; 90% confidence interval [CI]: 0.04, 0.43) and median overall survival (OS) was 37.3 vs 13.1 months (HR = 0.08; 90% CI: 0.01, 0.51). Methods: INSIGHT 2 is a global, open-label, Phase II trial of tepotinib + osimertinib in patients with advanced EGFR-mutant NSCLC. Following a protocol amendment in Apr 2020, the study is enrolling patients with acquired resistance to 1L osimertinib (radiological documentation of disease progression following previous objective clinical benefit) due to METamp by FISH (GCN ≥5 or MET/CEP7 ratio ≥2). Patients must be ≥18 years old, have an Eastern Cooperative Oncology Group performance status of 0/1, and normal organ function. Both tissue and liquid biopsy, obtained at the time of progression to osimertinib, will be sent for central confirmation of METamp. Liquid biopsy samples will also be used for exploratory biomarker evaluation. Enrollment is allowed based on local FISH testing while awaiting central confirmation of METamp. Patients will receive 500 mg QD (450 mg active moiety) tepotinib + 80 mg QD osimertinib until disease progression, unacceptable toxicity, or consent withdrawal. The study is anticipated to enroll 120 patients. The primary endpoint is objective response rate (ORR) by independent review (RECIST v1.1) in patients with METamp, centrally confirmed by FISH. Secondary endpoints include ORR by investigator assessment, duration of response, disease control, PFS, OS, pharmacokinetics, health-related quality of life, tolerability, and safety. An exploratory tepotinib monotherapy arm will enroll 12 patients to assess the contribution of tepotinib to the activity of the combination. At progression (determined by independent review committee), monotherapy patients can switch to combination treatment. These patients will be analyzed separately. Recruitment is ongoing, with > 300 patients prescreened. Approximately 100 sites in 17 countries in Europe, Asia, and North America are expected to participate. Approximately 15 sites will recruit patients in the US. Clinical trial information: NCT03940703.

Amivantamab in combination with lazertinib for the treatment of osimertinib-relapsed, chemotherapy-naïve EGFR mutant (EGFRm) non-small cell lung cancer (NSCLC) and potential biomarkers for response

9006

Background: Preliminary efficacy was observed with the combination of amivantamab, an EGFR-MET bispecific antibody, and lazertinib, a 3rd-generation tyrosine kinase inhibitor, in both treatment-naïve and osimertinib (osi)-relapsed patients (pts) with EGFRm NSCLC (Cho Ann Oncol 2020;31:S813). We present updated results of the combination in osi-relapsed pts, including an analysis of potential biomarkers of response. Methods: Pts with EGFR exon 19 deletion or L858R mutation NSCLC, who had progressed on osi without intervening chemotherapy, were enrolled in the combination cohort of the ongoing CHRYSALIS study (NCT02609776). With pre-treatment tumor biopsies and ctDNA collected prospectively, pts received the combination dose of 1050/1400 mg amivantamab + 240 mg lazertinib to assess safety and efficacy in the osi-relapsed population. Response was assessed by investigator per RECIST v1.1. Osi-resistance mutations or amplifications in EGFR/MET identified by next-generation sequencing (NGS) in either ctDNA or tumor biopsy (biomarker-positive [pos]), were evaluated for enriching response. Immunohistochemistry (IHC) staining for EGFR and MET expression was also explored as a potential biomarker for response. Results: Of the 45 osi-relapsed pts, 36% (95% CI, 22–51) had a confirmed response (1 complete response and 15 partial responses [PR]). At a median follow-up of 8.2 mo (1.0–11.8), 20/45 pts (44%) remain on treatment. With 11/16 pts (69%) continuing in response (2.6–9.6+ mo), median duration of response has not been reached (NR). The median progression-free survival (mPFS) was 4.9 mo (95% CI, 3.7–8.3). In total, 44/45 pts were evaluable by ctDNA and 29/45 by tumor NGS. Genetic testing identified 17 biomarker-pos pts, of whom 8 (47%) responded. Of the remaining 28 pts, 8 (29%) responded. Among these 28 pts, 18 had unknown mechanisms of osi-resistance (8 PR) and 10 had non-EGFR/MET mechanisms of resistance identified (none responded). The mPFS (95% CI) for biomarker-pos and remaining pts was 6.7 mo (3.4–NR) and 4.1 mo (1.4–9.5), respectively. Adequate tissue was available for 20 pts to perform IHC testing for EGFR and MET–9/10 (90%) IHC high (combined EGFR+MET H score>400) pts responded to treatment, while 1/10 IHC low pts responded to treatment. Conclusions: Treatment with the combination of amivantamab and lazertinib yielded responses in 36% of chemotherapy-naïve pts who progressed on osi. Among these pts, genetic EGFR and MET-based biomarkers of resistance identified a subgroup of pts more likely to respond to amivantamab and lazertinib, although additional pts lacking identified resistance markers also responded. An IHC-based approach may identify pts most likely to benefit from the combination regimen, but further investigation is warranted. Clinical trial information: NCT02609776.

Dynamic Management of Lung Cancer Care During Surging COVID-19

Management of patients with lung cancer continues to be challenging during the COVID-19 pandemic, due to the increased risk of complications in this subset of patients. During the COVID-19 surge in New York City, New York University Langone Health adopted triage strategies to help with care for lung cancer patients, with good surgical outcomes and no transmission of COVID-19 to patients or healthcare workers. Here, we will review current recommendations regarding screening and management of lung cancer patients during both a non-surge phase and surge phase of COVID-19.

KRYSTAL-2: A phase I/II trial of adagrasib (MRTX849) in combination with TNO155 in patients with advanced solid tumors with KRAS G12C mutation

TPS146

Background: KRAS is the most frequently mutated oncogene in cancer and a key mediator of the RAS/MAPK signaling cascade that promotes cellular growth and proliferation. KRAS G12C tumor mutations occur in approximately 14% of patients with lung adenocarcinoma and 3-4% of colorectal adenocarinoma. SHP2 is a phosphatase that acts as a key mediator of signaling from receptor tyrosine kinases (RTKs) to downstream RAS/MAPK pathways. Adagrasib (MRTX849) is a specific small-molecule investigational inhibitor of KRAS G12C that covalently binds to and locks mutant KRAS in its GDP-bound inactive form. Adagrasib has been optimized for a long half-life and extensive tissue distribution to enable inhibition throughout the entire dosing interval. Preliminary results from a Phase 1/2 study of adagrasib demonstrated promising antitumor activity and tolerability across multiple KRAS G12C tumor types. TNO155 is a selective inhibitor of SHP2 with demonstrated inhibition of RTK signaling and significant antitumor activity in preclinical models. Preclinical studies have shown that resistance to KRAS G12C inhibition may be mediated by SHP2-dependent feedback loops. Because KRAS G12C retains some level of cycling between GTP- and GDP-bound states, KRAS G12C that is not bound by inhibitor can activate downstream signaling. Active SHP2 functions to increase the active state of RAS proteins (including mutant KRAS) and also increases ERK pathway activation. Therefore, the addition of TNO155 to adagrasib may augment antitumor activity and overcome resistance by inhibiting cycling to GTP-bound KRAS and/or through inhibition of feedback activation and more comprehensively inhibiting downstream ERK signaling. In KRAS G12C human tumor models, adagrasib combined with a SHP2 inhibitor demonstrated greater activity compared to each agent alone. These data provide support for clinical evaluation of this combination in KRAS G12C tumors. Methods: KRYSTAL-2 is a multicenter Phase 1/2 study evaluating adagrasib and TNO155 in patients with advanced solid tumors harboring a KRAS G12C mutation. Overall objectives of the trial include evaluating safety, tolerability, and PK. The Phase 1 portion will evaluate adagrasib and TNO155 utilizing a modified Toxicity Probability Interval dose escalation design to identify maximum tolerated dose and recommended Phase 2 dose. The Phase 2 portion utilizes a Simon's optimal two-stage design to evaluate the clinical activity of adagrasib with TNO155 in 2 cohorts of up to 108 patients—CRC (54 patients) and NSCLC (54 patients). Efficacy endpoints include Objective Response Rate (RECIST 1.1), Duration of Response (DOR), Progression-free Survival (PFS), and Overall Survival (OS). The study is currently enrolling and patients will receive study treatment until disease progression, unacceptable adverse events, patient withdrawal, or death. Clinical trial information: NCT04330664.

Progression free survival (PFS) in Asian vs non-Asian patients (pts) with EGFR mutant non-small cell lung cancer (NSCLC) receiving osimertinib

e21679

Background: Third generation EGFR tyrosine kinase inhibitor (TKI) osimertinib demonstrated superior PFS and OS compared to earlier generation TKIs in pts with EGFR+ NSCLC. These pts are disproportionately Asian, female, and never-smokers. Contradictory data has been reported regarding the PFS and OS to osimertinib in Asian pts as compared to 1st and 2nd generation EGFR TKI. These inconsistencies warrant further investigation. The purpose of this study is to evaluate the PFS in Asian vs non-Asian pts with EGFR+ NSCLC receiving osimertinib. Methods: We conducted a single institution IRB approved retrospective study of pts with EGFR+ NSCLC. PFS was evaluated in pts treated from 1/2013 – 12/2019. Disease and treatment characteristics were summarized using frequency distributions and Kaplan-Meier curves for comparison of subgroups. Results: Of 190 EGFR+ pts: 52 (27%) Asian, 108 (57%) Caucasian, 125 (66%) female, 172 (91%) advanced disease, 107 (56%) never-smokers. Baseline characteristics in Asian and non-Asian pts were similar in regards to de-novo stage IV disease (71% vs 65%, p = 0.80), brain metastases (42% vs 54%, p = 0.48), and differed with regards to ever-smoking (29% vs 56%, p = 0.04). Treatment: 126/172 (73%) pts with advanced disease received TKI across all lines of therapy; 92/126 received osimertinib (22 (24%) 1st line; 45 (49%) 2nd line; 18 (19%) 3rd line; 7 (8%) ≥4th line). There were insufficient number of pts who received osimertinib in the 1st line to comment on differences in PFS between Asian and non-Asian pts. In the 2nd line, 19 Asian pts and 26 non-Asian pts received osimertinib, with no observed difference in PFS (median 15.4 v 13.8 months, p = 0.20). Moreover, Asian pts who received osimertinib as second line therapy had superior PFS (median 15.4 vs 9.6 months, p < 0.01) compared to Asian pts who received earlier generation TKIs, likely due to T790M resistance. Conclusions: Among second line advanced EGFR+ NSCLC, we did not observe a difference in PFS between Asian and non-Asian pts treated with osimertinib. Median PFS in Asian pts treated with osimertinib was longer compared to those treated with 1st or 2nd generation TKIs in the 2nd line setting. Our study highlights the the role of ethnic background in response to EGFR therapies and may warrant further study.

Amivantamab (JNJ-61186372), an anti-EGFR-MET bispecific antibody, in patients with EGFR exon 20 insertion (exon20ins)-mutated non-small cell lung cancer (NSCLC)

9512

Background: EGFR exon20ins-mutated NSCLC is generally refractory to EGFR tyrosine kinase inhibitors (TKIs) and is associated with poor prognosis. Amivantamab (JNJ-61186372) is a novel, fully human anti-EGFR-MET bispecific antibody whose mechanism of action can target both EGFR- and MET-driven disease and has shown monotherapy activity in patients (pts) with diverse EGFR mutant disease characterized by EGFR C797S, T790M, exon20ins, and MET amplification. We present preliminary results of pts with advanced NSCLC harboring exon20ins mutations from CHRYSALIS, an ongoing phase 1 study of amivantamab (NCT02609776). Methods: This study comprises a dose escalation phase in pts with advanced NSCLC and a dose expansion phase in pts with EGFR- and MET-mutated disease. This analysis includes all enrolled pts with exon20ins disease who received the recommended phase 2 dose (RP2D) of 1050 mg (1400 mg, pts ≥80 kg) amivantamab. Response was assessed by investigator per RECIST v1.1. Results: As of 30 Oct 2019, 50 pts with exon20ins mutations had received amivantamab at the RP2D. 39/50 pts were response-evaluable and had ≥2 disease assessments or had discontinued therapy prior to the assessment period; among these pts, 29 had prior platinum-based chemotherapy (PBCT). Median age for response-evaluable pts was 61 y (40–78), 51% were female, and median prior lines was 1 (0–7). In the 50 pts harboring exon20ins mutations treated at the RP2D, the most common adverse events (AEs) reported were rash (72%), infusion related reaction (60%), and paronychia (34%). Additional EGFR-related AEs included stomatitis (16%), pruritus (14%), and diarrhea (6%). Grade ≥3 AEs were reported in 36% of pts; 6% were treatment-related. One grade 3 diarrhea and no grade ≥3 rash was reported. Among the 39 response-evaluable pts, with a median follow-up of 4 months (1–26), the overall response rate (≥partial response [PR]) was 36% (95% CI, 21–53), and 41% (95% CI, 24–61) for the 29 pts who had prior PBCT. The clinical benefit rate (≥PR or stable disease ≥11 weeks) was 67% for response-evaluable pts and 72% for pts who had prior PBCT. Among all 14 responders, median duration of response was 10 months (1–16), with ongoing responses in 9 pts at data cutoff. Median progression-free survival was 8.3 months (95% CI, 3.0–14.8) for response-evaluable pts and 8.6 months (95% CI, 3.7–14.8) for pts who had prior PBCT. Conclusions: Amivantamab demonstrates robust and durable antitumor activity in pts with exon20ins disease, with a manageable safety profile. Clinical trial information: NCT02609776 .

A Prospective Study of Circulating Tumor DNA to Guide Matched Targeted Therapy in Lung Cancers

BACKGROUND

Liquid biopsy for plasma circulating tumor DNA (ctDNA) next-generation sequencing (NGS) is commercially available and increasingly adopted in clinical practice despite a paucity of prospective data to support its use.

METHODS

Patients with advanced lung cancers who had no known oncogenic driver or developed resistance to current targeted therapy (n = 210) underwent plasma NGS, targeting 21 genes. A subset of patients had concurrent tissue NGS testing using a 468-gene panel (n = 106). Oncogenic driver detection, test turnaround time (TAT), concordance, and treatment response guided by plasma NGS were measured. All statistical tests were two-sided.

RESULTS

Somatic mutations were detected in 64.3% (135/210) of patients. ctDNA detection was lower in patients who were on systemic therapy at the time of plasma collection compared with those who were not (30/70, 42.9% vs 105/140, 75.0%; OR = 0.26, 95% CI = 0.1 to 0.5, P < .001). The median TAT of plasma NGS was shorter than tissue NGS (9 vs 20 days; P < .001). Overall concordance, defined as the proportion of patients for whom at least one identical genomic alteration was identified in both tissue and plasma, was 56.6% (60/106, 95% CI = 46.6% to 66.2%). Among patients who tested plasma NGS positive, 89.6% (60/67; 95% CI = 79.7% to 95.7%) were also concordant on tissue NGS and 60.6% (60/99; 95% CI = 50.3% to 70.3%) vice versa. Patients who tested plasma NGS positive for oncogenic drivers had tissue NGS concordance of 96.1% (49/51, 95% CI = 86.5% to 99.5%), and directly led to matched targeted therapy in 21.9% (46/210) with clinical response.

CONCLUSIONS

Plasma ctDNA NGS detected a variety of oncogenic drivers with a shorter TAT compared with tissue NGS and matched patients to targeted therapy with clinical response. Positive findings on plasma NGS were highly concordant with tissue NGS and can guide immediate therapy; however, a negative finding in plasma requires further testing. Our findings support the potential incorporation of plasma NGS into practice guidelines.

PD-L1 expression, tumor mutational burden, and response to immunotherapy in patients with MET exon 14 altered lung cancers

Background

MET exon 14 alterations are actionable oncogenic drivers. Durable responses to MET inhibitors are observed in patients with advanced MET exon 14-altered lung cancers in prospective trials. In contrast, the activity of immunotherapy, PD-L1 expression and tumor mutational burden (TMB) of these tumors and are not well characterized.

Patients and methods

Patients with MET exon 14-altered lung cancers of any stage treated at two academic institutions were identified. A review of clinicopathologic and molecular features, and an analysis of response to single-agent or combination immune checkpoint inhibition were conducted. PD-L1 immunohistochemistry was carried out and TMB was calculated by estimation from targeted next-generation sequencing panels.

Results

We identified 147 patients with MET exon 14-altered lung cancers. PD-L1 expression of 0%, 1%-49%, and ≥50% were 37%, 22%, and 41%, respectively, in 111 evaluable tumor samples. The median TMB of MET exon 14-altered lung cancers was lower than that of unselected non-small-cell lung cancers (NSCLCs) in both independently evaluated cohorts: 3.8 versus 5.7 mutations/megabase (P < 0.001, n = 78 versus 1769, cohort A), and 7.3 versus 11.8 mutations/megabase (P < 0.001, n = 62 versus 1100, cohort B). There was no association between PD-L1 expression and TMB (Spearman's rho=0.18, P = 0.069). In response-evaluable patients (n = 24), the objective response rate was 17% (95% CI 6% to 36%) and the median progression-free survival was 1.9 months (95% CI 1.7-2.7). Responses were not enriched in tumors with PD-L1 expression ≥50% nor high TMB.

Conclusion

A substantial proportion of MET exon 14-altered lung cancers express PD-L1, but the median TMB is lower compared with unselected NSCLCs. Occasional responses to PD-1 blockade can be achieved, but overall clinical efficacy is modest.

JNJ-61186372 (JNJ-372), an EGFR-cMet bispecific antibody, in EGFR-driven advanced non-small cell lung cancer (NSCLC)

9009

Background: JNJ-372 binds EGFR and cMet to block ligand binding, promote receptor degradation, and trigger antibody-dependent cellular cytotoxicity in models of EGFR-mutated (EGFRm) NSCLC. Here we describe the ongoing phase 1 safety, pharmacokinetics (PK), and activity of JNJ-372 in patients (pts) with NSCLC, including 3rd generation tyrosine kinase inhibitor (3GTKI)-relapsed EGFRm NSCLC and EGFR Exon20ins disease. Methods: Pts received JNJ-372 (140–1400 mg) IV weekly for the first 28-day cycle and biweekly thereafter. 1050–1400 mg doses are being explored in dose expansion. Blood samples were collected for PK analyses. Efficacy by investigator per RECIST v1.1 in pts with EGFRm NSCLC treated at ≥700 mg is presented. Tumors were characterized by next-generation sequencing of circulating tumor (ct)DNA and/or tumor tissue. Results: As of 17 Jan 2019, 116 enrolled pts with NSCLC were treated. Median age was 63 years, 38% were male, 77% were Asian, and 97% had EGFR mutations. Mean duration of treatment was 3.8 months, longest exposure was 20 cycles. The PK data set included pts from Korea (77%) and the US (23%). At the 1050 mg dose, 72% of pts achieved average concentrations above the EC90 based on preclinical models. Adverse events (AEs; ≥20%) were rash (59%), infusion related reaction (58%), paronychia (28%), and constipation (22%). Additional EGFR/cMet-related AEs include stomatitis (17%), pruritis (15%), peripheral edema (11%), and diarrhea (7%). Grade ≥3 AEs were reported in 34% (8% treatment-related) with dyspnea (6%) and pneumonia (3%) most frequently observed. Among response-evaluable pts, 25/88 (28%) achieved best timepoint response of partial response (PR). 10/47 pts with prior 3GTKI therapy had best timepoint response of PR (6 confirmed), including 4 with C797S, 1 with cMet amplification, and 5 without identifiable EGFR/cMet-dependent resistance. 6/20 pts with Exon20ins had best timepoint response of PR (3 confirmed). Conclusions: JNJ-372 has a manageable safety profile consistent with EGFR and cMet inhibition. Preliminary responses were achieved in 3GTKI-relapsed disease, including C797S and cMet amplification, and Exon20ins disease; enrollment in dose expansion is ongoing. Clinical trial information: NCT02609776.

Afatinib in patients with metastatic or recurrent HER2-mutant lung cancers: a retrospective international multicentre study

INTRODUCTION

HER2 mutations occur in 1-3% of lung adenocarcinomas. With increasing use of next-generation sequencing at diagnosis, more patients with HER2-mutant tumours present for treatment. Few data are available to describe the clinical course and outcomes of these patients when treated with afatinib, a pan-HER inhibitor.

METHODS

We identified patients with metastatic or recurrent HER2-mutant lung adenocarcinomas treated with afatinib among seven institutions across Europe, Australia, and North America between 2009 and 2017. We determined the partial response rate to afatinib, types of HER2 mutations, duration of response, time on treatment, and survival.

RESULTS

We collected information on 27 patients with stage IV or recurrent HER2-mutant lung adenocarcinomas treated with afatinib. Of 23 patients evaluable for response, three partial responses were noted (13%, 95% confidence interval [CI] 4-33%). In addition, 57% of patients (13/23) had stable disease, and 30% (7/23) had progressive disease. We documented partial responses in patients with HER2 exon 20 insertions, including two with YVMA insertion and one with VAG insertion. Two patients with partial responses were previously treated with trastuzumab and pertuzumab. Median duration of response to afatinib was 6 months (range 5-10); median time on treatment was 3 months (range 1-30) and median overall survival from the date of diagnosis of metastatic or recurrent disease was 23 months (95% CI 18-53 months).

CONCLUSIONS

Afatinib is modestly active in patients with HER2-mutant lung adenocarcinomas, including responses after progression on prior HER2-targeted therapies. However, investigations into the biology of HER2-mutant lung adenocarcinomas and development of better HER2-directed therapies are warranted.

Activation of KRAS Mediates Resistance to Targeted Therapy in MET Exon 14-mutant Non-small Cell Lung Cancer

PURPOSE

MET exon 14 splice site alterations that cause exon skipping at the mRNA level (METex14) are actionable oncogenic drivers amenable to therapy with MET tyrosine kinase inhibitors (TKI); however, secondary resistance eventually arises in most cases while other tumors display primary resistance. Beyond relatively uncommon on-target MET kinase domain mutations, mechanisms underlying primary and acquired resistance remain unclear.

EXPERIMENTAL DESIGN

We examined clinical and genomic data from 113 patients with lung cancer with METex14. MET TKI resistance due to KRAS mutation was functionally evaluated using in vivo and in vitro models.

RESULTS

Five of 113 patients (4.4%) with METex14 had concurrent KRAS G12 mutations, a rate of KRAS cooccurrence significantly higher than in other major driver-defined lung cancer subsets. In one patient, the KRAS mutation was acquired post-crizotinib, while the remaining 4 METex14 patients harbored the KRAS mutation prior to MET TKI therapy. Gene set enrichment analysis of transcriptomic data from lung cancers with METex14 revealed preferential activation of the KRAS pathway. Moreover, expression of oncogenic KRAS enhanced MET expression. Using isogenic and patient-derived models, we show that KRAS mutation results in constitutive activation of RAS/ERK signaling and resistance to MET inhibition. Dual inhibition of MET or EGFR/ERBB2 and MEK reduced growth of cell line and xenograft models.

CONCLUSIONS

KRAS mutation is a recurrent mechanism of primary and secondary resistance to MET TKIs in METex14 lung cancers. Dual inhibition of MET or EGFR/ERBB2 and MEK may represent a potential therapeutic approach in this molecular cohort.

Impact of Baseline Steroids on Efficacy of Programmed Cell Death-1 and Programmed Death-Ligand 1 Blockade in Patients With Non-Small-Cell Lung Cancer

PURPOSE

Treatment with programmed cell death-1 or programmed death ligand 1 (PD-(L)1) inhibitors is now standard therapy for patients with lung cancer. The immunosuppressive effect of corticosteroids may reduce efficacy of PD-(L)1 blockade. On-treatment corticosteroids for treatment of immune-related adverse events do not seem to affect efficacy, but the potential impact of baseline corticosteroids at the time of treatment initiation is unknown. Clinical trials typically excluded patients who received baseline corticosteroids, which led us to use real-world data to examine the effect of corticosteroids at treatment initiation.

METHODS

We identified patients who were PD-(L)1-naïve with advanced non-small-cell lung cancer from two institutions-Memorial Sloan Kettering Cancer Center and Gustave Roussy Cancer Center-who were treated with single-agent PD-(L)1 blockade. Clinical and pharmacy records were reviewed to identify corticosteroid use at the time of beginning anti-PD-(L)1 therapy. We performed multivariable analyses using Cox proportional hazards regression model and logistic regression.

RESULTS

Ninety (14%) of 640 patients treated with single-agent PD-(L)1 blockade received corticosteroids of ≥ 10 mg of prednisone equivalent daily at the start of the PD-(L)1 blockade. Common indications for corticosteroids were dyspnea (33%), fatigue (21%), and brain metastases (19%). In both independent cohorts, Memorial Sloan Kettering Cancer Center (n = 455) and Gustave Roussy Cancer Center (n = 185), baseline corticosteroids were associated with decreased overall response rate, progression-free survival, and overall survival with PD-(L)1 blockade. In a multivariable analysis of the pooled population, adjusting for smoking history, performance status, and history of brain metastases, baseline corticosteroids remained significantly associated with decreased progression-free survival (hazard ratio, 1.3; P = .03), and overall survival (hazard ratio, 1.7; P < .001).

CONCLUSION

Baseline corticosteroid use of ≥ 10 mg of prednisone equivalent was associated with poorer outcome in patients with non-small-cell lung cancer who were treated with PD-(L)1 blockade. Prudent use of corticosteroids at the time of initiating PD-(L)1 blockade is recommended.

Abstract 1826: Oncogenic KRAS mediates resistance to MET targeted therapy in non-small cell lung cancer (NSCLC) with MET mutations that induce exon14 skipping

Mutations in MET that induce skipping of exon 14 and lead to reduced ubiquitin ligase-mediated turnover of this receptor tyrosine kinase (RTK) are detected in 3-4% of non-small cell lung cancer (NSCLC), approaching the prevalence of ALK-rearranged lung cancers. Preclinical and clinical studies have revealed that MET exon14 alterations are actionable oncogenic drivers that are amenable to therapy with MET kinase inhibitors such as crizotinib. However, similar to most kinase-driven cancers, despite initial benefit, acquired resistance to therapy is inevitable. Next-generation sequencing (MSK-IMPACT 468 gene panel) was performed on samples from 81 NSCLC patients with MET exon14 alterations, including 7 with paired pre- and post-treatment tumor samples. A concurrent KRAS G12 mutation was identified in 5 patients. In 4 of these patients, the KRAS mutation was present prior to receiving crizotinib. The KRAS mutation was acquired post-crizotinib in the remaining patient. These findings implicate KRAS activation as a potential mechanism of acquired resistance. Using isogenic and patient-derived in vitro and in vivo models harboring MET exon14 skipping alteration, we confirmed that the KRAS mutation results in constitutive activation of RAS/ERK signaling and cells expressing both MET exon14 skipping and KRAS mutations are refractory to MET inhibition. Dual inhibition of MET and MEK with crizotinib and trametinib, respectively, has an additive effect in cell line and xenograft models. Whereas concurrent KRAS mutation is an extremely rare event in EGFR- and ALK-driven NSCLC, our findings confirm KRAS mutation as a recurrent mechanism of primary or secondary resistance to MET-directed therapies in lung cancers harboring MET exon14 alterations. We provide a new potential therapeutic strategy for NSCLC patients with both MET exon14 alterations and KRAS mutations.

Citation Format: Ken Suzawa, Michael D. Offin, Christopher Kurzatkowski, Daniel Liu, Morana Vojnic, Roger S. Smith, Marissa Mattar, Inna Khodos, Elisa de Stanchina, Joshua K. Sabari, William W. Lockwood, Alexander E. Drilon, Marc Ladanyi, Romel Somwar. Oncogenic KRAS mediates resistance to MET targeted therapy in non-small cell lung cancer (NSCLC) with MET mutations that induce exon14 skipping [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1826.

Next-generation sequencing based detection of germline and somatic alterations in a patient with four metachronous primary tumors

INTRODUCTION

Multiple primary tumors (MPTs) are defined as two or more separate synchronous or metachronous neoplasms occurring in different sites in the same individual. These tumors differ in histology, as well as primary sites from which they arise. Risk factors associated with the occurrence of MPTs include germline alterations, exposure to prior cancer therapies, occupational hazards, and lifestyle and behavioral influences.

CASE REPORT

We present a case of a patient who was diagnosed with four metachronous primary tumors. In 2013, she was diagnosed with serous proliferations associated with psammomatous bodies of primary peritoneal origin (pT3NxM0). This was followed by invasive ductal carcinoma of the breast (stage pT2N0Mx, histological grade III/III) in 2014, melanoma (stage pT2bNxMx) in 2016 that further advanced to the lung and brain in 2017, and a low-grade lung carcinoid in 2017. To better understand the biology of this patient's MPTs, we performed next-generation sequencing (NGS) to assess for both somatic and germline alterations. The treatment course for this patient aims to target the tumor with the strongest prognostic value, namely her malignant melanoma, and has contributed favorably to the overall survival of this patient.

CONCLUSION

We report the clinical and genomic landscape of a patient with MPTs who had no identifiable unique somatic or germline mutations to explain her predilection to cancer. The treatment course and overall prognosis for this patient is important for understanding future cases with unrelated, metachronous MPTs, the occurrence of which cannot always be explained by underlying genetic mechanisms.

Relevance of genetic alterations in squamous and small cell lung cancer

The precision medicine revolution has led to the development and US FDA approval of multiple targeted therapies in non-squamous non-small cell lung cancers, including tyrosine kinase inhibitors targeting EGFR, ALK, and ROS1. However, the development of targeted therapies for squamous cell lung cancers (SQCLCs) and small cell lung cancers (SCLCs) has lagged behind and the mainstay of systemic therapy for most patients with metastatic disease remains chemotherapy; which has seen little meaningful progress over the past three decades. The ideal of precision medicine in these diseases may appear elusive; however, recent comprehensive genomic analysis of SQCLC and SCLC has led to multiple breakthroughs in our understanding of the biology of these diseases and has led to new therapeutic approaches currently under active clinical investigation. This review will focus on the therapeutic relevance of these alterations in their respective diseases and new insights into promising therapeutics currently under investigation.

Unravelling the biology of SCLC: implications for therapy

Small-cell lung cancer (SCLC) is an aggressive malignancy associated with a poor prognosis. First-line treatment has remained unchanged for decades, and a paucity of effective treatment options exists for recurrent disease. Nonetheless, advances in our understanding of SCLC biology have led to the development of novel experimental therapies. Poly [ADP-ribose] polymerase (PARP) inhibitors have shown promise in preclinical models, and are under clinical investigation in combination with cytotoxic therapies and inhibitors of cell-cycle checkpoints.Preclinical data indicate that targeting of histone-lysine N-methyltransferase EZH2, a regulator of chromatin remodelling implicated in acquired therapeutic resistance, might augment and prolong chemotherapy responses. High expression of the inhibitory Notch ligand Delta-like protein 3 (DLL3) in most SCLCs has been linked to expression of Achaete-scute homologue 1 (ASCL1; also known as ASH-1), a key transcription factor driving SCLC oncogenesis; encouraging preclinical and clinical activity has been demonstrated for an anti-DLL3-antibody-drug conjugate. The immune microenvironment of SCLC seems to be distinct from that of other solid tumours, with few tumour-infiltrating lymphocytes and low levels of the immune-checkpoint protein programmed cell death 1 ligand 1 (PD-L1). Nonetheless, immunotherapy with immune-checkpoint inhibitors holds promise for patients with this disease, independent of PD-L1 status. Herein, we review the progress made in uncovering aspects of the biology of SCLC and its microenvironment that are defining new therapeutic strategies and offering renewed hope for patients.

Liquid biopsy in the clinic: A prospective study of plasma circulating tumor DNA (ctDNA) next generation sequencing (NGS) in patients with advanced non-small cell lung cancers to match targeted therapy

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Background: Liquid biopsy for plasma ctDNA NGS is a rapidly evolving science. Plasma ctDNA assays are commercially available and are increasingly adopted in the community with a paucity of evidence-based guidance. We set out to study the optimal timing and utility of plasma ctDNA NGS in clinic. Methods: Pts with advanced NSCLC who were driver unknown, defined as not having prior tissue NGS or clinical concern for tumor heterogeneity that may affect treatment decisions, were eligible. Peripheral blood was collected in a Streck tube (10mL), DNA extracted, and subjected to a bias-corrected hybrid-capture 21 gene targeted NGS assay in a CLIA lab with unique reads at 3000x and sensitive detection at variant allele frequency above 0.1% (ResolutionBio Bellevue, WA). Pts also had concurrent tissue NGS via MSK IMPACT. Clinical endpoints included detection of oncogenic drivers in plasma, ability to match pts to targeted therapy, concordance and turnaround time of plasma and tissue NGS. Results: Forty-one pts were prospectively accrued. Plasma ctDNA detected an oncogenic driver in 39% (16/41) of pts, of whom 17% (7/41) were matched to targeted therapy; including pts matched to clinical trials for HER2 exon 20 insertionYVMA, BRAF L597Q and MET exon14. Mean turnaround time for plasma was 7 days (4-12) and 28 days (20-43) for tissue. Plasma ctDNA was detected in 56% (23/41) of pts; detection was 40% (8/20) if blood was drawn on active therapy and 71% (15/21) if drawn off therapy, either at diagnosis or progression (Odds ratio 0.28, 95% CI 0.06 - 1.16; p = 0.06). All pts had concurrent tissue NGS; of the 10 samples resulted, there was 100% driver concordance between tissue and plasma in pts drawn off therapy. Conclusions: In pts who were driver unknown or who had clinical concern for tumor heterogeneity, plasma ctDNA NGS identified a variety of oncogenic drivers with a short turnaround time and matched them to targeted therapy. Plasma ctDNA detection was more frequent at diagnosis of metastatic disease or at progression. A positive finding of an oncogenic driver in plasma is highly specific, but a negative finding may still require tissue biopsy.

Lung cancers with mutations in EGFR exon 18: Molecular characterization and clinical outcomes in response to tyrosine kinase inhibitors

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Background: Little data is available to guide clinical management of individuals with less common oncogenic drivers such as exon 18 mutations (ex18m) in EGFR. To better understand the impact of these rare mutations on treatment outcomes, we reviewed clinicopathologic data in patients (pts) with ex18m treated with tyrosine kinase inhibitors (TKI) in EGFR-mutant lung cancers. Methods: Pts with EGFR ex18m were detected via molecular diagnostics using Sequenom™, FoundationOne™ or MSK IMPACT™ NGS testing from 2003-2016. We reviewed their clinical data for molecular alterations in EGFR, treatment outcomes in response to TKI (time on treatment) and median overall survival (OS). Results: We identified mutations in EGFR ex18m in 63 pts. Median age at diagnosis was 68; 63% were women; 29% never smokers. Overall, 74 ex18m were found in 63 pts, including: G719A = 38, G719S = 11, G719C = 8, E709K = 6, E709_T710delinsD = 6, E709A = 3, G719D = 2. E709 and G719 co-mutations in ex18 were found in 9 pts, and 1 pt was found to have 3 separate tumors, each with a distinct ex18m. 29/63 (46%) patients with ex18m had a co-occurring EGFR mutation: 9 with another ex18m; 20 with ex19-21m. Using our IMPACT NGS, the median number of co-mutations was 8 (range 1-17). Two out of 63 pts had a pre-treatment T790M mutation. The 25 pts with non-metastatic disease presented in the following stages: IA = 19; IB = 3; IIB = 1; IIIA = 2; IIIB = 2. 34/38 pts with metastatic disease were treated with the following first-line EGFR-TKIs: erlotinib = 28, afatinib = 5, osimertinib = 1. Median duration on TKI treatment in months was: erlotinib = 10 mo, (range 1-25), afatinib = 3 mo (range 2-9), osimertinib = 4 mo. Median OS from the date of diagnosis of metastatic disease was 22 months (95% CI 18-29). In comparison, a similar cohort of pts with sensitizing EGFR exon19del/L858R mutations had a median OS of 31 months (95% CI 28-33) (Naidoo Cancer2015). Conclusions: Almost half of ex18m occur concurrently with another EGFR mutation. Overall, ex18m pts have a shorter median OS when compared to similar patient cohorts. EGFR-TKIs appear to be an effective treatment for pts with ex18m in EGFR-mutant lung cancers.

Afatinib in patients with metastatic HER2-mutant lung cancers: An international multicenter study

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Background: Human epidermal growth factor 2 ( HER2, ERBB2) mutations have been identified as oncogenic drivers in 3% of lung cancers. Afatinib is an irreversible tyrosine kinase inhibitor of HER1 (EGFR), HER2 and HER4 and has been described in case reports to have activity in HER2-mutant lung cancers. However, there is little data to inform the clinical use of afatinib. Methods: We reviewed patients with metastatic HER2-mutant lung cancers treated with afatinib among 7 institutions between 2009 and 2016. The primary endpoint was investigator assessed overall response rate using RECIST v1.1. Other data collected included types of HER2mutations, duration of afatinib treatment and overall survival. Results: We identified 27 patients with metastatic HER2-mutant lung cancers treated with afatinib. Median age at diagnosis was 63 (range 40 to 84); majority were men (n = 16; 59%) and never-smokers (n = 18; 67%). All tumors were adenocarcinomas, and the majority were Stage IV at initial diagnosis (n = 16; 59%). A 12-base pair (bp) in-frame insertion YVMA in exon 20 (p.A775_G776insYVMA) was present in 16 patients (59%). In addition, there were three 9-bp insertions, two 3-bp insertions and two single bp substitutions (L755F and D769H) in exon 20; two single bp substitutions (S310F) in exon 8; one exon 17 V659E mutation; and one single-nucleotide polymorphism (Ile655Val). Median duration on afatinib was 2 months (range 1 to 27); median line of prior treatment was 3 (range 1 to 6). Eight patients had previously received trastuzumab prior to afatinib and one concurrently with afatinib. Overall response rate was 15% (n = 4; 95% CI 4 to 34%); the four partial responses lasted 5, 5, 6 and 10 months. The 3 longest partial responders had a 12-bp insertion in exon 20 (YVMA); the remaining partial responder had a 9-bp insertion in exon 20. Median overall survival from diagnosis date of metastatic disease was 23 months (95% CI 18 to 62). Conclusions: Afatinib produced partial responses in 15% of patients with metastatic HER2-mutant lung cancers, including insertion YVMA. Our findings confirm the activity of afatinib and provide data supporting a framework for its use in the care of patients with HER2-mutant lung cancers.