Amivantamab plus chemotherapy with and without lazertinib in EGFR-mutant advanced NSCLC after disease progression on osimertinib: primary results from the phase III MARIPOSA-2 study

BACKGROUND

Amivantamab plus carboplatin-pemetrexed (chemotherapy) with and without lazertinib demonstrated antitumor activity in patients with refractory epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) in phase I studies. These combinations were evaluated in a global phase III trial.

PATIENTS AND METHODS

A total of 657 patients with EGFR-mutated (exon 19 deletions or L858R) locally advanced or metastatic NSCLC after disease progression on osimertinib were randomized 2 : 2 : 1 to receive amivantamab-lazertinib-chemotherapy, chemotherapy, or amivantamab-chemotherapy. The dual primary endpoints were progression-free survival (PFS) of amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy. During the study, hematologic toxicities observed in the amivantamab-lazertinib-chemotherapy arm necessitated a regimen change to start lazertinib after carboplatin completion.

RESULTS

All baseline characteristics were well balanced across the three arms, including by history of brain metastases and prior brain radiation. PFS was significantly longer for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy [hazard ratio (HR) for disease progression or death 0.48 and 0.44, respectively; P < 0.001 for both; median of 6.3 and 8.3 versus 4.2 months, respectively]. Consistent PFS results were seen by investigator assessment (HR for disease progression or death 0.41 and 0.38 for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy, respectively; P < 0.001 for both; median of 8.2 and 8.3 versus 4.2 months, respectively). Objective response rate was significantly higher for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (64% and 63% versus 36%, respectively; P < 0.001 for both). Median intracranial PFS was 12.5 and 12.8 versus 8.3 months for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (HR for intracranial disease progression or death 0.55 and 0.58, respectively). Predominant adverse events (AEs) in the amivantamab-containing regimens were hematologic, EGFR-, and MET-related toxicities. Amivantamab-chemotherapy had lower rates of hematologic AEs than amivantamab-lazertinib-chemotherapy.

CONCLUSIONS

Amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy improved PFS and intracranial PFS versus chemotherapy in a population with limited options after disease progression on osimertinib. Longer follow-up is needed for the modified amivantamab-lazertinib-chemotherapy regimen.

Selumetinib with and without erlotinib in KRAS mutant and KRAS wild-type advanced nonsmall-cell lung cancer

BACKGROUND

KRAS mutations in NSCLC are associated with a lack of response to epidermal growth factor receptor inhibitors. Selumetinib (AZD6244; ARRY-142886) is an oral selective MEK kinase inhibitor of the Ras/Raf/MEK/ERK pathway.

PATIENTS AND METHODS

Advanced nonsmall-cell lung cancer (NSCLC) patients failing one to two prior regimens underwent KRAS profiling. KRAS wild-type patients were randomized to erlotinib (150 mg daily) or a combination of selumetinib (150 mg daily) with erlotinib (100 mg daily). KRAS mutant patients were randomized to selumetinib (75 mg b.i.d.) or the combination. The primary end points were progression-free survival (PFS) for the KRAS wild-type cohort and objective response rate (ORR) for the KRAS mutant cohort. Biomarker studies of ERK phosphorylation and immune subsets were carried out.

RESULTS

From March 2010 to May 2013, 89 patients were screened; 41 KRAS mutant and 38 KRAS wild-type patients were enrolled. Median PFS in the KRAS wild-type arm was 2.4 months [95% confidence interval (CI) 1.3-3.7] for erlotinib alone and 2.1 months (95% CI 1.8-5.1) for the combination. The ORR in the KRAS mutant group was 0% (95% CI 0.0% to 33.6%) for selumetinib alone and 10% (95% CI 2.1% to 26.3%) for the combination. Combination therapy resulted in increased toxicities, requiring dose reductions (56%) and discontinuation (8%). Programmed cell death-1 expression on regulatory T cells (Tregs), Tim-3 on CD8+ T cells and Th17 levels were associated with PFS and overall survival in patients receiving selumetinib.

CONCLUSIONS

This study failed to show improvement in ORR or PFS with combination therapy of selumetinib and erlotinib over monotherapy in KRAS mutant and KRAS wild-type advanced NSCLC. The association of immune subsets and immune checkpoint receptor expression with selumetinib may warrant further studies.

Phase I study of the halichondrin B analogue eribulin mesylate in combination with cisplatin in advanced solid tumors

BACKGROUND

Eribulin mesylate is a synthetic macrocyclic ketone analogue of Halichondrin B that has demonstrated high antitumor activity in preclinical and clinical settings. This phase I study aimed to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), and pharmacokinetics in combination with cisplatin (CP) in patients with advanced solid tumours.

METHODS

Thirty-six patients with advanced solid tumours received eribulin mesylate 0.7-1.4 mg m(-2) and CP 60-75 mg m(-2). Eribulin mesylate was administered on days 1, 8, and 15 in combination with CP day 1 every 28-day cycle. The protocol was amended after dose level 4 (eribulin mesylate 1.4 mg m(-2), CP 60 mg m(-2)) when it was not feasible to administer eribulin mesylate on day 15 because of neutropenia; the treatment schedule was changed to eribulin mesylate on days 1 and 8 and CP on day 1 every 21 days.

RESULTS

On the 28-day schedule, three patients had DLT during the first cycle: grade (G) 4 febrile neutropenia (1.0 mg m(-2), 60 mg m(-2)); G 3 anorexia/fatigue/hypokalemia (1.2 mg m(-2), 60 mg m(-2)); and G 3 stomatitis/nausea/vomiting/fatigue (1.4 mg m(-2), 60 mg m(-2)). On the 21-day schedule, three patients had DLT during the first cycle: G 3 hypokalemia/hyponatremia (1.4 mg m(-2), 60 mg m(-2)); G 4 mucositis (1.4 mg m(-2), 60 mg m(-2)); and G 3 hypokalemia (1.2 mg m(-2), 75 mg m(-2)). The MTD and recommended phase II dose was determined as eribulin mesylate 1.2 mg m(-2) (days 1, 8) and CP 75 mg m(-2) (day 1), on a 21-day cycle. Two patients had unconfirmed partial responses (PR) (pancreatic and breast cancers) and two had PR (oesophageal and bladder cancers).

CONCLUSIONS

On the 21-day cycle, eribulin mesylate 1.2 mg m(-2), administered on days 1 and 8, in combination with CP 75 mg m(-2), administered on day 1 is well tolerated and showed preliminary anticancer activity.

The FEN1 E359K germline mutation disrupts the FEN1-WRN interaction and FEN1 GEN activity, causing aneuploidy-associated cancers

Polymorphisms and somatic mutations in Flap Endonuclease 1 (FEN1), an essential enzyme involved in DNA replication and repair, can lead to functional deficiencies of the FEN1 protein and a predisposition to cancer. We identified a FEN1 germline mutation which changed residue E359 to K in a patient whose family had a history of breast cancer. We determined that the E359K mutation, which is in the protein-protein domain of FEN1, abolished the interaction of FEN1 with Werner Syndrome protein (WRN), an interaction which is critical for resolving stalled DNA replication forks. Furthermore, although the flap endonuclease activity of FEN1 E359K was unaffected, it failed to resolve bubble structures, which requires the FEN1 gap dependent endonuclease (GEN) activity. To determine the etiological significance of E359K, we established a mouse model containing this mutation. E359K mouse embryonic fibroblasts (MEF) were more sensitive to DNA cross-linking agents that cause replication forks to stall. Cytological analysis suggested that the FEN1-WRN interaction was also required to for telomere stability; mutant cell lines had fragile telomeres, increased numbers of spontaneous chromosomal anomalies and higher frequencies of transformation. Moreover, the incidence of cancer was significantly higher in mice homozygous for FEN1 E359K than in wild-type mice, suggesting that the FEN1 E359K mutation is oncogenic.

Decline in serum soluble E-cadherin and low baseline matrix metalloproteinase-9 are associated with response to combination celecoxib and erlotinib therapy in advanced non-small cell lung cancer

7640

Background: Cyclooxygenase-2 (COX-2) overexpression may mediate resistance to EGFR TK inhibition through prostaglandin E2 (PGE2)-dependent promotion of epithelial to mesenchymal transition (EMT). Thomson, et al. reported that the suppression of epithelial markers such as E-cadherin led to resistance to erlotinib (Cancer Res 2005;65:9455). In addition, PGE2 downregulates E-cadherin expression by upregulating transcriptional repressors including ZEB1 and Snail, as described by Dohadwala et al (Cancer Res 2006;66:5338). These findings suggest that COX-2 inhibition may enhance the efficacy of EGFR TKI therapy in NSCLC. Methods: A phase I, dose escalation trial to was performed investigating the combination of celecoxib and erlotinib in pts with advanced NSCLC. Soluble E-cadherin (sEC) was evaluated by ELISA in pt serum at baseline and weeks 4 and 8 of treatment. Other markers of COX-2 gene expression were evaluated by ELISA, including matrix metalloproteinase (MMP)-9, MMP-2 and tissue inhibitor of MMP (TIMP1). Results: 22 pts were enrolled and 21 were evaluable for the determination of the optimal dose, toxicity assessment and response (reported in Clin Cancer Res 2006;12:3381). Here we report serum sEC and MMP-9 levels, which were analyzed according to best response (PR, SD or PD) in 21 pts. SEC was analyzed according to best response (PR, SD or PD). We found a significant decrease in sEC between baseline and week 8 in pts with PR when compared to those with SD or PD (p = 0.021). In pts who responded to the combination therapy, baseline MMP-9 was significantly lower compared to non-responders (p = 0.006). Conclusions: SEC, MMP-9 and other downstream markers of COX-2 gene expression may be useful for assessing response to combination celecoxib and erlotinib in pts with advanced NSCLC. A randomized Phase II trial is planned comparing erlotinib and celecoxib with erlotinib plus placebo in advanced NSCLC, to evaluate the efficacy of this combination therapy and to assess these and other biomarkers in both serum and tumor tissue. Supported by ASCO Young Investigator Award, UCLA Lung Cancer SPORE NCI P50 CA 90388 and GLAVAHS Career Development Award.

No significant financial relationships to disclose.

Targeted COX-2 and EGFR TK inhibition in advanced non-small cell lung cancer

7179

Background: Prostaglandin E2 (PGE2) activates Erk/MAPK signaling pathway in an epidermal growth factor receptor (EGFR) tyrosine kinase (TK)-resistant manner as a result of cyclooxygenase-2 (COX-2) overexpressed in lung cancer. Because 10% of patients respond to this class of drugs, evaluating agents that may overcome resistance and determining the population of patients most likely to respond is crucial. Imaging tumor metabolism by positron emission tomography with the glucose analog fluorodeoxyglucose (FDG-PET) is an innovative approach for assessing the efficacy of targeted agents. We studied the combination of COX-2 inhibition (celecoxib) and EGFR inhibition (erlotinib) in a phase I trial in advanced non-small cell lung cancer (NSCLC) and added FDG-PET imaging as a potential method for evaluation of early response. Methods: A phase I, dose escalation trial to investigate the optimal biologic dose (OBD) of the combination of celecoxib and erlotinib in pts with refractory stage IIIB/IV NSCLC. FDG-PET was evaluated in selected patients at baseline, week 2 and week 8 of study treatment. Tumor metabolic activity was quantitatively assessed by standardized uptake values (SUV). Changes in SUV were compared to CT imaging at week 8 with response defined by RECIST criteria. Results: Twenty-two subjects were enrolled and 21 were evaluable for the determination of the OBD, toxicity assessment and response. Rash and skin-related effects were the most commonly reported toxicities. Seven patients demonstrated partial responses and five patients developed stable disease. Responses were seen in patients both with and without EGFR activating mutations. The duration of partial response was 24–93 wks. TTP was 83 weeks in one patient with stable disease. A patient evaluated by FDG-PET had a significant decrease in SUV (-45%) at week 2 which corresponded to partial responses by RECIST at week 8. Conclusions: FDG-PET as a measure of tumor glucose utilization appears to be a promising tool for assessing early response to targeted therapies. A randomized Phase II trial is planned comparing erlotinib and celecoxib with erlotinib plus placebo in advanced NSCLC, and evaluating FDG-PET response as a marker of early efficacy. Supported by UCLA Lung Cancer SPORE NCI P50 CA 90388, GLAVAHS CDA and STOP Cancer Award.

[Table: see text]