Two clinical scenarios illustrated shared decision-making in practice: a 58-year-old woman with TP53 mutation, L858R, and asymptomatic brain metastases drew unanimous consensus for treatment intensification with either FLAURA2 or MARIPOSA, given her high-risk features and flexible schedule.
The debate examined whether amivantamab-lazertinib or osimertinib-chemotherapy more favorably reshapes resistance biology, with the MARIPOSA team citing data showing lower rates of MET amplification (7.3% vs. 13.1%) and secondary EGFR mutations (1.4% vs. 7.6%) compared to osimertinib monotherapy, alongside a potential immune-activating effect of amivantamab and a possible curve-flattening signal suggesting disease course modification.
Panelists agreed that subcutaneous amivantamab represents meaningful progress over the IV formulation, nearly eliminating infusion reactions, reducing dosing frequency to every four weeks, and lowering high-grade dermatologic toxicity, although grade 1-2 rash and the burden of the COCOON prophylaxis regimen remain relevant considerations for patients.
The debate centered on CNS efficacy comparisons between MARIPOSA and FLAURA2, with the key distinction being that MARIPOSA mandated serial brain MRIs for all patients, enabling full intracranial PFS analysis across all 429 participants, whereas FLAURA2 only required serial imaging in patients with baseline CNS metastases, limiting the robustness of its CNS data.
The TOP trial, a phase three study focused exclusively on TP53-mutant EGFR-mutant non-small cell lung cancer, validated the FLAURA2 findings in this high-risk subset, showing a striking PFS benefit of 34.0 versus 15.6 months (HR 0.44) for osimertinib plus chemotherapy over monotherapy, with a favorable duration of response of 32.7 versus 15.9 months, though overall survival data remain immature.
The FLAURA2 phase three trial demonstrated that adding platinum-based chemotherapy to osimertinib significantly improved outcomes over osimertinib monotherapy in first-line EGFR-mutant non-small cell lung cancer, with a median PFS of 29.4 versus 19.9 months and a statistically significant overall survival benefit of 47.5 versus 37.6 months.
The COPERNICUS study, an ongoing phase two trial, evaluated amivantamab-based regimens in EGFR-mutant non-small cell lung cancer across two cohorts, first-line and post-osimertinib progression, with a key focus on implementing mandatory prophylactic skin and DVT regimens, resulting in dramatically lower rash rates (4% grade 3+) compared to the original MARIPOSA trial.
Panelists discuss the pivotal MARIPOSA trial, which examined combining amivantamab with lazertinib versus osimertinib monotherapy, showing improvements in progression-free survival (23.7 vs. 16.6 months), overall survival, CNS efficacy, and particularly strong benefits in high-risk subgroups such as TP53-mutant patients. Safety data from the trial highlighted the importance of prophylactic measures, especially for rash and other adverse events, noting that with current prophylaxis protocols, serious toxicity rates have been significantly reduced compared to the original study.
Misako Nagasaka, MD, PhD, summarizes the key takeaways: proactive AE management, CNS vigilance, and strategic sequencing as hallmarks of modern care for EGFR-mutant NSCLC.
The discussion underscores the role of multidisciplinary coordination in maintaining adherence, quality of life, and long-term therapeutic benefit.
Experts debate when to introduce chemotherapy, how to manage its cumulative toxicity, and how to de-escalate maintenance regimens.
The panel explores integrating molecular data to guide therapy selection and optimize sequencing strategies after resistance emerges.
A second case illustrates clinical decision-making after progression on osimertinib, highlighting diagnostic re-biopsy and ctDNA testing.
The conversation shifts to how dual EGFR-MET inhibition reduces resistance mutations and molecular heterogeneity compared with osimertinib monotherapy.
The panel reviews components of the COCOON prophylactic regimen and the safe use of temporary dose modifications to maintain adherence.
Discussion centers on early dermatologic AEs with amivantamab plus lazertinib, emphasizing prevention protocols and staff education.
The physicians share real-world imaging schedules, triggers for adding local therapy, and lessons from serial MRI data in the MARIPOSA trial.
The panel examines a 59-year-old woman with small brain metastases, addressing therapy selection to balance CNS control, survival, and quality of life.
Experts discuss applying emerging evidence from MARIPOSA and FLAURA2 to first-line decision-making in EGFR-mutated disease.
Misako Nagasaka, MD, PhD, Dr. Nagasaka introduces the panel and outlines the session’s focus on applying new EGFR-mutated NSCLC data to practice, with emphasis on CNS control and toxicity prevention.
Treatment with lorlatinib might be effective regardless of the presence of central nervous system metastases, according to Misako Nagasaka, MD, PhD.
Most central nervous system events with lorlatinib were grade 1 or 2 in the phase 3 CROWN trial.
Treatment with lorlatinib did not increase cardiovascular events among patients with ALK-positive non–small cell lung cancer in the CROWN trial.
At 5 years, 60% of patients who received lorlatinib in the phase 3 CROWN study achieved progression-free survival.
Panelist discusses how HER2-directed tumor-agnostic treatments are likely to see expanded applications across multiple cancer types, driven by improved biomarker testing and emerging clinical evidence. This approach may become increasingly personalized through enhanced molecular profiling, potentially leading to more precise patient selection and combination strategies.
Panelist discusses how the DESTINY-PanTumor02 study enrolled 267 patients with different tumor types, including endometrial, cervical, ovarian, bladder, biliary tract, and pancreatic cancer.
Panelist discusses how HER2-directed tumor-agnostic therapies represent an emerging treatment paradigm focused on targeting HER2 mutations regardless of cancer type. Current agents such as trastuzumab deruxtecan show promise across multiple tumor types that express HER2, moving beyond traditional cancer-specific approaches. This precision medicine strategy may expand treatment options and improve outcomes for patients with HER2-altered cancers who previously had limited therapeutic choices.
Panelist discusses how the DESTINY-Lung02 trial was a dose optimization study where patients with HER2-mutated non–small cell lung cancer (NSCLC) were randomly assigned to a starting dose of 5.4 mg/kg vs 6.4 mg/kg of trastuzumab deruxtecan (T-DXd). DESTINY-Lung03 was a frontline study for HER2 overexpression in NSCLC looking at different combinations of treatment with T-DXd and immunotherapy agents with or without chemotherapy.
Panelist discusses how HER2 testing evaluates protein overexpression, gene amplification, and mutations. Although breast and gastric cancers typically show overexpression/amplification, other tumors more commonly harbor mutations.
Introduction to HER2-Directed Tumor-Agnostic Approaches
October 15th 2024
November 20th 2023
