Category: Precision Oncology

Late Breaking Abstract – 2025 ASCO GI Symposium: OPDIVO® Plus YERVOY® Superior to OPDIVO® Alone in MSI-H/MMR Deficient Metastatic Colorectal Cancer

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SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

The majority of CRC cases (about 75 %) are sporadic whereas the remaining 25 % of the patients have a family history of the disease. Only 5-6 % of patients with CRC with a family history background are due to inherited mutations in major CRC genes, while the rest are the result of accumulation of both genetic mutations and epigenetic modifications of several genes. Colorectal Cancer is a heterogeneous disease classified by its genetics, and even though the diagnosis of Colorectal Cancer in the US is dropping among people 65 years and older, the incidence has been rising in the younger age groups, with 12% of Colorectal Cancer cases diagnosed in people under age 50.

The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, with the expression of tumor-specific neoantigens at the surface of cancer cells, triggering an enhanced antitumor immune response. MSI is therefore a hallmark of defective/deficient DNA MisMatchRepair (dMMR) system and occurs in 15% of all colorectal cancers. Defective MMR can be a sporadic or heritable event. Approximately 65% of the MSI high colon tumors are sporadic and when sporadic, the DNA MMR gene is MLH1. Defective MMR can manifest as a germline mutation occurring in MMR genes including MLH1, MSH2, MSH6 and PMS2. This produces Lynch Syndrome often called Hereditary Nonpolyposis Colorectal Carcinoma – HNPCC, an Autosomal Dominant disorder that is often associated with a high risk for Colorectal and Endometrial carcinoma, as well as several other malignancies including Ovary, Stomach, Small bowel, Hepatobiliary tract, Brain and Skin. MSI is a hallmark of Lynch Syndrome-associated cancers. MSI high tumors tend to have better outcomes and this has been attributed to the abundance of tumor infiltrating lymphocytes in these tumors from increase immunogenicity. These tumors therefore are susceptible to blockade with immune checkpoint inhibitors.

MSI testing is performed using a PCR or NGS based assay and MSI-High refers to instability at 2 or more of the 5 mononucleotide repeat markers and MSI-Low refers to instability at 1 of the 5 markers. Patients are considered Micro Satellite Stable (MSS) if no instability occurs. MSI-L and MSS are grouped together because MSI-L tumors are uncommon and behave similar to MSS tumors. Tumors considered MSI-H have deficiency of one or more of the DNA MMR genes. MMR gene deficiency can be detected by ImmunoHistoChemistry (IHC). NCCN Guidelines recommend MMR or MSI testing for all patients with a history of Colon or Rectal cancer. Unlike Colorectal and Endometrial cancer, where MSI-H/dMMR testing is routinely undertaken, the characterization of Lynch Syndrome across heterogeneous MSI-H/dMMR tumors is unknown.

Nivolumab (OPDIVO®) is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, whereas Ipilimumab (YERVOY®) is a fully human immunoglobulin G1 monoclonal antibody that blocks Immune checkpoint protein/receptor CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152). Blocking the Immune checkpoint proteins unleashes the T cells, resulting in T cell proliferation, activation and a therapeutic response. The FDA in 2018, granted accelerated approval to Ipilimumab for use in combination with Nivolumab, based on CheckMate-142, for the treatment of patients with MSI-H or dMMR metastatic CRC, that has progressed following treatment with a Fluoropyrimidine, Oxaliplatin, and Irinotecan. The FDA in July, 2017, granted accelerated approval to single agent Nivolumab for treatment of this same group of patients.

The CheckMate 8HW is an ongoing Phase III, multinational, open-label, randomized trial evaluating Nivolumab plus Ipilimumab as compared with Nivolumab alone or chemotherapy, in patients with MSI-H or dMMR metastatic CRC. In this study, patients with unresectable or mCRC and MSI-H/dMMR status by local testing who had received 0-1 prior line of therapy were randomly assigned in a 2:2:1 ratio to receive either Nivolumab monotherapy (N=353), Nivolumab plus Ipilimumab combination therapy (N=354), or the investigator’s choice of chemotherapy (mFOLFOX6 or FOLFIRI with or without Bevacizumab or Cetuximab (N=132). Patients who had previously received two or more prior lines of therapy for unresectable or metastatic disease were randomly assigned, in a 1:1 ratio, to receive Nivolumab plus Ipilimumab or Nivolumab alone. In the Nivolumab monotherapy arm, patients received Nivolumab 240 mg IV once every two weeks for six doses, followed by 480 mg IV every four weeks. In the Nivolumab plus Ipilimumab arm, patients were given Nivolumab 240 mg IV plus Ipilimumab 1mg/kg IV every three weeks for four doses, followed by Nivolumab 480 mg IV every four weeks. The median patient age was 64 years and tumor location was in the right colon in two thirds of the patients. Treatments continued until disease progression or unacceptable toxicity in all treatment groups or a maximum of 2 years. The dual Primary end points were Progression-Free Survival (PFS) as determined by Blinded Independent Central Review (BICR) comparing Nivolumab plus Ipilimumab to chemotherapy in the first-line therapy setting, and PFS comparing Nivolumab monotherapy to Nivolumab plus Ipilimumab across all lines of therapy, in patients with centrally confirmed MSI-H/dMMR metastatic CRC. At a median follow-up of 31.5 months the results from the prespecified interim analysis (the primary analysis) showed that the PFS outcomes were significantly better with Nivolumab plus Ipilimumab than with chemotherapy (HR=0.21; P<0.001).

The researchers herein reported the first results from the other dual Primary endpoint of PFS for Nivolumab plus Ipilimumab versus Nivolumab monotherapy across all lines of therapy in patients with centrally confirmed MSI-H/dMMR metastatic CRC. Of all the randomized patients 296 in the Nivolumab plus Ipilimumab group and 286 in the Nivolumab monotherapy group had centrally confirmed MSI-H/dMMR status. With a median follow-up of 47.0 months, Nivolumab plus Ipilimumab demonstrated clinically meaningful and statistically significant improvement in PFS by BICR versus Nivolumab monotherapy, with a median PFS Not Reached (NR) in the Nivolumab plus Ipilimumab group, compared to 39.3 months for those on Nivolumab monotherapy (HR=0.62; P= 0.0003). The PFS rates at 12, 24, and 36 months were higher in the Nivolumab plus Ipilimumab group at 76%, 71%, 68% versus 63%, 56%, 51% for Nivolumab monotherapy.

The Objective Response Rate (ORR) was significantly higher with Nivolumab plus Ipilimumab at 71%, compared to 58% with Nivolumab alone (P=0.0011). No new safety concerns were identified

It was concluded that the CheckMate 8HW study met its dual Primary endpoints, with Nivolumab plus Ipilimumab demonstrating a statistically significant and clinically meaningful improvement in PFS compared to Nivolumab monotherapy across all lines of therapy in MSI-H/dMMR metastatic CRC. Moreover, Nivolumab plus Ipilimumab was associated with higher ORR, confirming its potential as a new standard of care for patients with MSI-H/dMMR metastatic CRC. The CheckMate 8HW study is a pivotal contribution to the treatment landscape of MSI-H/dMMR metastatic Colorectal cancer, providing compelling evidence for the use of Nivolumab plus Ipilimumab in the first-line and beyond.

First results of nivolumab (NIVO) plus ipilimumab (IPI) vs NIVO monotherapy for microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC) from CheckMate 8HW. Andre T, Elez E, Lenz H-J, et al. J Clin Oncol 43, 2025 (suppl 4; abstr LBA143)

SIGNATERA® ctDNA Assay Can Guide Therapy in Early Stage Colorectal Cancer

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SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

It is estimated that approximately 30% of patients with Stage II or III CRC and 60-70% of patients after oligometastatic resection experience recurrence. Adjuvant chemotherapy for patients with resected, locally advanced, node-positive (Stage III) colon cancer has been the standard of care since the 1990s. However, not all patients with Stage III disease benefit from adjuvant chemotherapy. In the IDEA trial, the absolute Disease Free Survival benefit of adjuvant chemotherapy for the lowest-risk Stage III group and the highest-risk group was 8% and 20%, respectively, suggesting that a substantial number of patients with low-risk Stage III cancer can safely forgo adjuvant chemotherapy or be considered for treatment de-escalation. Even though 80% of patients with Stage II colon cancer are cured with surgery alone, adjuvant chemotherapy is recommended for patients who have Stage II colon cancer with high-risk clinicopathological features, including tumor penetration of the serosa (T4 disease). However, the benefit of adjuvant chemotherapy for patients with Stage II disease remains unclear, with less than 5% of patients benefiting from adjuvant chemotherapy. There is therefore an unmet need for more precise markers to predict risk of recurrence after surgery for resectable colon cancer, other than clinicopathological risk factors, and thus avoid exposure to unnecessary chemotherapy.

Circulating Tumor DNA (ctDNA) refers to DNA molecules that circulate in the bloodstream after cell apoptosis or necrosis, and can be detected in the cell-free component of peripheral blood samples (Liquid Biopsy) in almost all patients with advanced solid tumors including advanced CRC. ctDNA is a valuable biomarker and is directly evaluated for evidence of Minimal Residual Disease and allows early detection of relapse. Several studies have shown that detectable ctDNA following curative intent surgery for early stage cancers, including those with Stage II colon cancer, is associated with a very high risk of recurrence (more than 80%) without further adjuvant therapy. It has remained unclear whether adjuvant treatment is beneficial for these ctDNA-positive patients who are at high risk for recurrence.

The BESPOKE CRC trial is a multicenter, prospective, observational study, designed to evaluate the role of Natera’s SIGNATERA® assay in informing adjuvant chemotherapy decisions for patients with surgically resected pathologic Stage II and III Colorectal Cancer (CRC). SIGNATERA® test is a personalized, tumor-informed ctDNA (circulating tumor DNA) assay for tracking 16 tumor-specific mutations in the blood for Minimal Residual Disease (MRD) determination and molecular monitoring. This study aimed to assess whether ctDNA could improve the decision-making process for adjuvant chemotherapy, thereby influencing the course of treatment and ultimately, patient outcomes.

This study included 1780 patients who had undergone surgical resection for Stage II or III CRC. These patients were enrolled in the study and were followed for their ctDNA status at various time points after their resection. The first ctDNA sample was taken for MRD 2 to 6 weeks following surgery (MRD time point). Subsequent samples were collected at 2, 4, and 6 months, and then every 3 months up to 24 months after resection. The surveillance ctDNA collection started at 6 months or later from surgical resection. The treating oncologists were provided with the ctDNA results of their patients and were allowed to base treatment decisions on these findings, within the context of standard-of-care guidelines. After exclusions, 1166 patients remained in the final analysis, 694 patients in the adjuvant chemotherapy cohort and 472 patients in the observation cohort. The median age of the study participants was 61.8 years, majority of the patients were male (56.7%), most patients had stage III CRC (55.7%), 59.5% of patients received adjuvant chemotherapy, while 83.9% of the participants did not experience a recurrence during the study period. The Primary endpoint of this study was to evaluate the impact of ctDNA testing on adjuvant treatment decisions, as well as the rates of asymptomatic CRC recurrences. Secondary endpoints included the MRD clearance rate, survival rates of MRD-negative patients, Overall Survival, and Patient-Reported Outcomes. The median follow-up was 23.9 months

ctDNA and Disease-Free Survival (DFS)
The study found that postoperative ctDNA positivity was a strong predictor of inferior Disease-Free Survival (DFS) in patients with both Stage II and III disease. At the MRD time point (first ctDNA sample 2-6 weeks post surgery), 7.54% of patients with Stage II disease (N= 517) tested positive for MRD versus 28.35% of patients with Stage III disease (N= 649). These findings were crucial for determining which patients might be at higher risk of recurrence.

  • Among Stage II patients, those with positive postoperative ctDNA had a significantly lower 2-year DFS rate of 45.9%, compared to 91.8% in ctDNA-negative patients (HR=11.23; P <0.0001).
  • Among Stage III patients, those with positive ctDNA were also associated with poorer DFS, with a 2-year DFS rate of 35.5% versus 87.4% for ctDNA-negative patients (HR=8.33; P <0.0001).

Further analyses showed that positive ctDNA at the first surveillance time point was linked with an inferior DFS (HR=20.63; P <0.0001). Patients who became positive for ctDNA at any time during surveillance had a 26.4-times higher risk of recurrence compared to those who remained ctDNA-negative.

ctDNA Clearance and Treatment Efficacy
One of the most compelling findings of the study was the correlation between ctDNA clearance during and after adjuvant chemotherapy and improved DFS. Patients whose ctDNA was cleared during treatment had significantly better outcomes:

  • Hazard ratio for DFS at 3 months after chemotherapy: 0.43 (P <.0001)
  • Hazard ratio for DFS at 6 months: 0.31 (P <.0001)

These results suggest that ctDNA clearance could be a powerful marker for assessing the effectiveness of adjuvant chemotherapy, reinforcing its potential as a treatment monitoring tool.

Recurrence Detection and Metastasis-Directed Therapy
The ctDNA test demonstrated high sensitivity in detecting disease recurrence, particularly in the liver, which had the highest sensitivity at 96%. It also showed high sensitivities in detecting recurrences in low-shedding sites like the lung (76%) and peritoneum (79%). Bone and abdominal wall recurrences had a sensitivity of 100%, though the small number of such cases limits the ability to draw firm conclusions.

Of the 188 patients who experienced disease recurrence, 86% had a prior positive ctDNA test. Notably, 30% of those patients received metastasis-directed therapy, with 81% of them undergoing surgical intervention. This emphasizes the potential of serial ctDNA monitoring in improving early detection of recurrences and facilitating more effective interventions, including metastasis-directed therapy, which could provide these patients with a chance for a cure.

Impact of Adjuvant Chemotherapy in MRD-Positive vs MRD-Negative Patients
The study also highlighted the differing effects of adjuvant chemotherapy in MRD-positive versus MRD-negative patients. While MRD-negative patients saw no significant difference in DFS regardless of whether they received chemotherapy or observation, MRD-positive patients showed a clear benefit from adjuvant chemotherapy:

  • 2-year DFS rates for MRD-positive patients was 40.3% with chemotherapy versus 24.7% with observation (HR=0.48; P =0.0008).
  • 2-year DFS rates for MRD-negative patients was 89.7% with chemotherapy versus 89.5% with observation (HR=0.93; P =0.03).

These results underscore the potential of using ctDNA as a tool to help personalize treatment strategies, offering chemotherapy to those who are most likely to benefit (MRD-positive patients) and sparing others from unnecessary treatment.

Summary of Key Findings

  • Tumor-informed ctDNA assays had a significant impact on adjuvant treatment decisions, influencing chemotherapy de-escalation in 16.3% of Stage II/III CRC cases.
  • Postoperative ctDNA positivity correlated with inferior DFS, making it a strong prognostic tool for identifying high-risk patients.
  • ctDNA clearance during and after chemotherapy was associated with improved DFS, highlighting its potential to monitor treatment efficacy.
  • ctDNA assays demonstrated high sensitivity in detecting recurrences, particularly in the liver, and influenced the use of metastasis-directed therapy.
  • Adjuvant chemotherapy showed a clear benefit in MRD-positive patients, further solidifying the role of this assay in personalizing treatment strategies for CRC patients.

This trial positions ctDNA as a pivotal tool in managing CRC, not only as a prognostic marker but also as a means to optimize treatment and improve patient outcomes.

Circulating tumor DNA for detection of molecular residual disease (MRD) in patients (pts) with stage II/III colorectal cancer (CRC): final analysis of the BESPOKE CRC sub-cohort. Shah P, Aushev V, Ensor J, et al. J Clin Oncol. 2025;43(suppl 4):15. doi:10.1200/JCO.2025.43.4_suppl.15

Prolonged Survival Benefit with LYNPARZA® in BRCA Mutated Early Stage Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 319,750 new cases of breast cancer will be diagnosed in 2025 and about 42,680 individuals will die of the disease, largely due to metastatic recurrence.

DNA can be damaged due to errors during its replication or as a result of environmental exposure to UV radiation from the sun or other toxins. The tumor suppressor genes such as BRCA1 (Breast Cancer 1) and BRCA2 help repair damaged DNA and thus play an important role in maintaining cellular genetic integrity, failing which these genetic aberrations can result in malignancies. The BRCA1 gene is located on the long (q) arm of chromosome 17 whereas BRCA2 is located on the long arm of chromosome 13. Mutations in BRCA1 and BRCA2 account for about 20 to 25 percent of hereditary breast cancers and about 5 to 10 percent of all breast cancers. These mutations can be inherited from either of the parents and a child has a 50 percent chance of inheriting this mutation, and the deleterious effects of the mutations are seen even when a second copy of the gene in an individual is normal. Patients with BRCA mutations can present with aggressive, high-risk disease and are at a high risk of recurrence following completion of multimodality therapy including surgery, radiation, and chemotherapy. This is an area of unmet need, warranting identification of additional novel and effective therapies.

BRCA1 and BRCA2 are tumor suppressor genes and they recognize and repair double strand DNA breaks via Homologous Recombination (HR) pathway. Homologous Recombination is a DNA repair pathway utilized by cells to accurately repair DNA double-stranded breaks during the S and G2 phases of the cell cycle, and thereby maintain genomic integrity. The PARP (Poly ADP Ribose Polymerase) family of enzymes include PARP1 and PARP2, and is a related enzymatic pathway that repairs single strand breaks in DNA. In a BRCA mutant, the cancer cell relies solely on PARP pathway for DNA repair to survive.

Olaparib (LYNPARZA®) is a PARP inhibitor, that traps PARP onto DNA at sites of single-strand breaks, thereby preventing their repair and generate double-strand breaks. These breaks cannot be repaired accurately in tumors harboring defects in Homologous Recombination Repair pathway genes, such as BRCA1 or BRCA2 mutations, and this leads to cumulative DNA damage and tumor cell death.

OlympiA is a multicenter, randomized, placebo-controlled, double-blind, Phase III trial of adjuvant Olaparib after neoadjuvant/adjuvant chemotherapy, in patients with germline BRCA1/2 mutations, and high risk HER2-negative early breast cancer. This trial enrolled 1836 patients, including triple-negative and Hormone Receptor positive (HR-positive) breast cancer. All enrolled patients had already received standard adjuvant or neoadjuvant chemotherapy, surgery and if needed, radiation therapy, for early stage breast cancer (Stage II-III). Inclusion criteria required that patients have a high risk of disease recurrence. Patients with triple-negative breast cancer who received adjuvant chemotherapy were required to have axillary node–positive disease or an invasive primary tumor measuring at least 2 cm. Patients who were treated with neoadjuvant chemotherapy were required to have residual invasive breast cancer in the breast or resected lymph nodes (no pathological Complete Response from neoadjuvant therapy). Patients who were treated with adjuvant chemotherapy for HR-positive, HER2-negative breast cancer were required to have 4 or more pathologically confirmed positive lymph nodes. Patients were randomized 1:1 to receive Olaparib 300 mg PO BID continuously for 1 year (N=921) or placebo (N=915). Endocrine therapy and bisphosphonates were allowed. Treatment groups were well balanced. The median age was 42 years, germline mutations were present in BRCA1 in 72% of the patients, in BRCA2 in 27% of the patients, 82% of the patients had triple-negative breast cancer, 18% had HR-positive and HER2 negative disease, 62% were premenopausal and 38% were postmenopausal, 50% of the patients had received adjuvant chemotherapy and 50% had received neoadjuvant chemotherapy. The Primary endpoint was Invasive Disease Free Survival (IDFS) and Secondary endpoints included Distant DFS (DDFS), Overall Survival (OS) and Safety. At the pre-specified interim analysis (2.5 years), the estimated 3-year Invasive DFS was 85.9% for patients who received Olaparib compared with 77.1% for those who received placebo (HR=0.58; P<0.001), representing a 42% reduction in the risk of Invasive DFS with Olaparib compared to placebo. The 3-year Distant DFS was 87.5% versus 80.4% respectively (HR=0.57; P<0.001). The researchers in this updated analysis reported the results of the third pre-specified interim analysis with median follow-up of 6.1 years (maximum follow-up of 9.6 years).

The treatment benefit with Olaparib was maintained with longer follow up, and was similar to previously reported results. The Invasive DFS at 6 years was 79.6% in the Olaparib-treated group versus 70.3% in the placebo group, with an absolute difference of 9.3%, favoring the addition of Olaparib (HR=0.65). The Distant DFS at 6 years was 83.5% versus 75.7%, respectively, with an absolute difference of 7.8% (HR=0.65). The 6-year Overall Survival rate was 87.5% in the Olaparib group versus 83.2% in the placebo group, with a 28% reduction in the risk of death (HR=0.72). The benefit with adjuvant Olaparib was consistent across all key subgroups, including for patients with high risk and HR-positive disease.

Fewer cases of BRCA-associated cancers such as contralateral invasive and non-invasive breast cancers, new primary ovarian cancer and new primary fallopian tube cancer were reported, with adjuvant Olaparib versus placebo. Further, there was no increase in the risk of developing secondary myelodysplastic syndrome or acute myeloid leukemia.

It was concluded that at 6.1 years median follow-up, one year of adjuvant treatment with Olaparib after neoadjuvant or adjuvant chemotherapy continues to demonstrate meaningful improvements in Invasive DFS, Distant DFS and OS in patients with germline BRCA pathogenic variants and high risk, HER2-negative breast cancer, including those with HR-positive tumors. This study highlights the importance of BRCA testing in early stage breast cancer. Perhaps considering one year of adjuvant Olaparib followed by a CDK4/6 inhibitor in HR-positive, BRCA-positive, high risk HER2-negative early stage breast cancer patients, may be a reasonable approach.

Garber J: OlympiA-Phase 3, multicenter, randomized placebo-controlled trial of adjuvant olaparib after (neo)adjuvant chemotherapy in patients with germline BRCA1/BRCA2 pathogenic variants and high-risk HER2-negative primary breast cancer: Longer-term follow-up. 2024 San Antonio Breast Cancer Symposium. Abstract GS1-09. Presented December 11, 2024.

FDA Approves LUMAKRAS® with VECTIBIX® for KRAS G12C-mutated Colorectal Cancer

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SUMMARY: The FDA on January 16, 2025, approved Sotorasib (LUMAKRAS®) with Panitumumab (VECTIBIX®) for adult patients with KRAS G12C-mutated metastatic ColoRectal Cancer (mCRC), as determined by an FDA-approved test, who have received prior Fluoropyrimidine, Oxaliplatin, and Irinotecan-based chemotherapy. The FDA also approved the therascreen KRAS RGQ PCR Kit (QIAGEN GmbH) as a companion diagnostic device to aid in identifying patients with colorectal cancer whose tumors harbor KRAS G12C mutations and who may be eligible for LUMAKRAS® with VECTIBIX®.

Colorectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 154,270 new cases of CRC will be diagnosed in the United States in 2025 and about 52,900 patients will die of the disease. The lifetime risk of developing CRC is about 1 in 23.

Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. First line treatment of metastatic CRC includes Oxaliplatin or Irinotecan, in combination with a Fluoropyrimidine and Leucovorin (FOLFOX or FOLFIRI respectively), along with a VEGF targeting agent such as Bevacizumab or EGFR targeting agents such as Cetuximab (ERBITUX®) and Panitumumab. Patients with Stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Patients who progress following these therapies are considered to have refractory disease. These patients sometimes are rechallenged with previously administered chemotherapeutic agents, but often receive Regorafenib (STIVARGA®), an oral multikinase inhibitor with antiangiogenic activity, or LONSURF® (a fixed dose combination of Trifluridine and Tipiracil). These therapies, however, have shown limited efficacy.

The KRAS (Kirsten rat sarcoma viral oncogene homologue) proto-oncogene encodes a protein that is a member of the small GTPase super family. The KRAS gene provides instructions for making the KRAS protein, which is a part of a signaling pathway known as the RAS/MAPK pathway. By relaying signals from outside the cell to the cell nucleus, the protein instructs the cell to grow, divide and differentiate. KRAS gene is in the Ras family of oncogenes, which also includes two other genes, HRAS and NRAS. When mutated, oncogenes have the potential to change normal cells to cancer cells. KRAS is the most frequently mutated oncogene in human cancers and these cancers are often associated with resistance to targeted therapies and poor outcomes. The KRAS G12C mutation occurs in approximately 12-15% of Non Small Cell Lung Cancers (NSCLC) and in 3-5% of colorectal cancers and other solid cancers. G12C is a single point mutation with a Glycine-to-Cysteine substitution at codon 12. This substitution favors the activated state of KRAS, amplifying signaling pathways that lead to oncogenesis.

Sotorasib is a small molecule that specifically and irreversibly inhibits KRAS G12C protein and traps KRAS G12C in the inactive GDP-bound state, thus blocking downstream proliferation and survival signaling. Unlike the efficacy of single-agent KRAS G12C inhibitors in Non Small Cell Lung Cancer with KRAS G12C mutation, KRAS G12C inhibition alone has limited activity in patients with colorectal cancer. This has been attributed to upstream reactivation of the Epidermal Growth Factor Receptor (EGFR) pathway resulting in treatment-induced resistance, following selective inhibition of KRAS G12C. However, dual KRAS G12C and EGFR blockade can overcome treatment resistance in patients with colorectal cancer with KRAS G12C mutation. In the CodeBreaK 101 Phase 1b trial involving patients with chemorefractory colorectal cancer with mutated KRAS G12C, the Response Rate was 30% with Sotorasib plus Panitumumab, as compared with 9.7% with Sotorasib monotherapy.

The present FDA approval was based on CodeBreaK 300 trial, which is an international, multicenter, open-label, randomized, active-controlled Phase III study, conducted to evaluate the efficacy and safety of two different doses of Sotorasib (960 mg and 240 mg) in combination with Panitumumab as compared with the investigator’s choice of standard-care therapy (Trifluridine-Tipiracil or Regorafenib) in patients with chemorefractory metastatic colorectal cancer with KRAS G12C mutation. A lower dose of Sotorasib 240 mg orally once daily was tested in this study because of the nonlinear pharmacokinetic properties of Sotorasib. A total of 160 patients were randomly assigned in a 1:1:1 ratio to receive Sotorasib 960 mg orally once daily plus Panitumumab 6 mg/kg IV every 2 weeks (the 960 mg Sotorasib/Panitumumab group; N=53), Sotorasib 240 mg orally once daily plus Panitumumab (the 240 mg Sotorasib/Panitumumab group; N=53), with each treatment cycle repeating every 28 days, or the investigator’s choice of standard of care therapy which could be either Trifluridine-Tipiracil 35 mg/m2 (up to a maximum of 80 mg per dose) orally twice daily on days 1-5 and days 8-12 every 28 days, or Regorafenib 160 mg orally once daily for the first 21 days of each 28-day cycle (N=54). Treatment continued until disease progression or unacceptable toxicities. The median age was 61 years and majority of patients had more than 2 or more lines of previous anti-cancer therapy. KRAS G12C mutation was confirmed by prospective central molecular testing. Randomization was stratified according to previous use of antiangiogenic therapy, the time from initial diagnosis of metastatic disease to randomization and ECOG-PS. The Primary end point was Progression Free Survival (PFS) as assessed by Blinded Independent Central Review (BICR). Key Secondary end points included Overall Survival (OS) and Objective Response Rate (ORR) and Duration of Response (DOR).

After a median follow up of 7.8 months, both Sotorasib combinations (960 mg and 240 mg) plus Panitumumab demonstrated significantly longer PFS compared to standard of care therapy. The median PFS was 5.6 months and 3.9 months in the 960 mg Sotorasib/Panitumumab and 240 mg Sotorasib/Panitumumab groups, respectively, as compared with 2.2 months in the standard of care group (HR for 960 mg group=0 49; P=0.006) (HR for 240 mg group=0.58; P=0.03). The improvement in PFS was observed across key subgroups, including tumor sideness/primary tumor location, prior lines of therapy, and the presence or absence of liver metastases. The Objective Response Rate was 26.4%, 5.7%, and 0% in the 960 mg Sotorasib/Panitumumab, 240 mg Sotorasib/Panitumumab, and standard of care groups, respectively and the median DOR was 4.4 months in the 960 mg Sotorasib/Panitumumab group. Overall Survival data is immature. While this trial was not powered to compare the two Sotorasib/Panitumumab groups directly, the 960 mg dose appeared to yield more clinically significant benefits than the 240 mg dose, across all efficacy endpoints, without additional toxic effects. The final analysis of PFS for patients randomized to the 240 mg Sotorasib/Panitumumab arm compared to the standard of care groups was not statistically significant.
Grade 3 or higher treatment-related adverse events occurred in 35.8%, 30.2%, and 43.1% of patients, respectively. Skin-related toxic effects and hypomagnesemia were the most common adverse events observed with Sotorasib/Panitumumab.

It was concluded from this study that Sotorasib 960 mg in combination with Panitumumab resulted in significantly longer Progression Free Survival and a higher Objective Response Rate than standard of care treatment. Ongoing analysis and longer follow-up will provide additional insights into Overall Survival outcomes.

Sotorasib plus Panitumumab in Refractory Colorectal Cancer with Mutated KRAS G12C. Fakih MG, Salvatore L, Esaki T, et al. N Engl J Med 2023;389:2125-2139.

FDA Grants Accelerated Approval to BIZENGRI® for Non Small Cell Lung Cancer and Pancreatic Adenocarcinoma

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SUMMARY: The FDA on December 4, 2024, granted accelerated approval to Zenocutuzumab-zbco (BIZENGRI®) for adults with advanced, unresectable, or metastatic Non-Small Cell Lung Cancer (NSCLC) harboring a neuregulin 1 (NRG1) gene fusion with disease progression on or after prior systemic therapy, or advanced, unresectable, or metastatic pancreatic adenocarcinoma harboring a NRG1 gene fusion with disease progression on or after prior systemic therapy. This represents the first FDA approval of a systemic therapy for patients with NSCLC or pancreatic adenocarcinoma harboring an NRG1 gene fusion.

Genomic rearrangements involving the neuregulin 1 (NRG1) gene have been implicated in a variety of solid tumors, including lung, breast, pancreas, ovarian, and prostate cancers. NRG1 fusions are rare oncogenic drivers occurring in less than 1% of solid tumors, highly enriched in KRAS-wild-type pancreatic adenocarcinoma and invasive mucinous adenocarcinoma of the lung. NRG1 fusions produce chimeric ligands that activate the ERBB Receptor Tyrosine Kinase (RTK) family, a group of proteins frequently exploited by cancer cells to promote tumor growth. In lung cancer, NRG1 fusions are associated with poor prognosis in patients with lung cancer, with low Response Rates to standard chemotherapy and immunotherapy, and a short Overall Survival.

The ERBB RTK family includes EGFR (ERBB1), HER2 (ERBB2), HER3 (ERBB3), and HER4 (ERBB4). These proteins mediate crucial cell signaling pathways that regulate growth and survival. They can be oncogenically activated by ligand stimulation such as NRG1 fusion proteins binding to HER3 or HER4, mutations and translocations that may confer constitutive enzymatic activity, such as EGFR kinase domain mutations, the EGFRvIII variant (where the extracellular region of EGFR is deleted), EGFR fusions or gene amplification, or protein overexpression resulting in increasing receptor abundance on cell surfaces to amplify signaling.

NRG1 preferentially binds to HER3 and HER4, promoting their heterodimerization with other ERBB family members like HER2 and EGFR. This interaction is critical because HER3, a pseudokinase, lacks intrinsic enzymatic activity and depends on phosphorylation by its heterodimer partners. The activated HER3 forms docking sites for SH2-domain proteins, triggering multiple downstream signal transduction pathways like the PI3K pathway, which drive proliferation and survival.

Zenocutuzumab is a bispecific humanized immunoglobulin G1 (IgG1) containing two different Fab arms targeting the extracellular domains of HER2 and HER3. The HER2-targeting arm binds HER2, concentrating the antibody locally and positioning it (Dock) to block NRG1 binding to HER3 (Dock-and-block mechanism). The HER3-targeting arm prevents HER3 from undergoing the conformational changes necessary for heterodimerization with HER2 and EGFR. This dual targeting halts HER3 phosphorylation, disrupting downstream oncogenic signaling. Moreover, the glycoengineered IgG1 backbone of Zenocutuzumab enhances its affinity for Fc receptors, boosting Antibody-Dependent Cellular Cytotoxicity (ADCC)-a mechanism by which immune cells destroy antibody-coated tumor cells.

The present approval is supported by the Phase 1/2 eNRGy ongoing trial, which is an open-label, multicenter, multicohort, dose-escalation study of Zenocutuzumab, in patients with solid tumors with a NRG1 fusion. Enrolled patients had a median of one prior line of therapy, including platinum chemotherapy (72%) and Afatinib (11%). The median patient age was 64 years and most were female (62%), and 51% were Asian. The most common NRG1 fusion partners were CD74 (57%), SLC3A2 (22%), SDC4/7 (9%), and CDH1/2 (3%). Most NRG1 fusions were identified by RNA sequencing (81%), followed by DNA sequencing (14%). Patients received Zenocutuzumab 750 mg IV every 2 weeks until disease progression. The major efficacy outcome measures were confirmed Overall Response Rate (ORR) and Duration of Response (DOR), determined by Blinded Independent Central Review.

The ORR for NSCLC was 33% and median DOR was 7.4 months. The ORR for pancreatic adenocarcinoma was 40% and the DOR was 3.7-16.6 months. In the pooled safety population, the most common adverse reactions were diarrhea, musculoskeletal pain, fatigue, nausea, infusion-related reactions, dyspnea, rash, constipation, vomiting, abdominal pain, and edema. The most common Grade 3 or 4 laboratory abnormalities were increased gamma-glutamyl transferase, anemia, thrombocytopenia and hyponatremia.

It was concluded from this analysis that Zenocutuzumab provided robust and durable efficacy in advanced NRG1 positive NSCLC and pancreatic adenocarcinoma, with a well-tolerated safety profile, and represents a potential first and best-in-class therapy for patients with NRG1 fusion solid tumors.

https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-zenocutuzumab-zbco-non-small-cell-lung-cancer-and-pancreatic

FDA Grants Accelerated Approval to BRAFTOVI® with ERBITUX® and mFOLFOX6 for Metastatic CRC with a BRAF V600E Mutation

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SUMMARY: The FDA on December 20, 2024, granted accelerated approval to Encorafenib (BRAFTOVI®) in combination with Cetuximab (ERBITUX®) and modified Fluorouracil, Leucovorin, and Oxaliplatin (mFOLFOX6) for patients with metastatic colorectal cancer with a BRAF V600E mutation, as detected by an FDA-approved test (Qiagen therascreen BRAF V600E RGQ polymerase chain reaction kit). ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 152,810 new cases of CRC were diagnosed in the United States in 2024 and about 53,010 patients died of the disease. The lifetime risk of developing CRC is about 1 in 23.

Advanced colon cancer is often incurable and standard chemotherapy when combined with anti EGFR (Epidermal Growth Factor Receptor) targeted monoclonal antibodies such as VECTIBIX® (Panitumumab) and ERBITUX® (Cetuximab) as well as anti VEGF agent AVASTIN® (Bevacizumab), have demonstrated improvement in Progression Free Survival (PFS) and Overall Survival (OS). The benefit with anti EGFR agents however is only demonstrable in patients with metastatic CRC (mCRC) whose tumors do not harbor KRAS mutations in codons 12 and 13 of exon 2 (KRAS Wild Type). It is now also clear that even among the KRAS Wild Type patient group about 15-20% have other rare mutations such as NRAS and BRAF mutations, which confer resistance to anti EGFR agents. Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Approximately 8-15% of all metastatic CRC tumors present with BRAF V600E mutations, and BRAF V600E is recognized as a marker of poor prognosis in this patient group. These patients tend to have aggressive disease with a higher rate of peritoneal metastasis and do not respond well to standard treatment intervention. Approximately 20% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group.

The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. The BRAF V600E mutations results in constitutive activation of the MAP kinase pathway. Inhibiting BRAF can transiently reduce MAP kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR. It should be noted that BRAF V600E-mutated CRC is inherently less sensitive to BRAF inhibition than Malignant Melanoma.

BRAFTOVI® (Encorafenib) is a BRAF inhibitor and has target binding characteristics that differ from other BRAF inhibitors such as ZELBORAF® (Vemurafenib) and TAFINLAR® (Dabrafenib), with a prolonged target dissociation half-life and higher potency. The FDA in 2020, approved Encorafenib in combination with Cetuximab (ERBITUX®) for the treatment of adult patients with metastatic ColoRectal Cancer (mCRC) with a BRAF V600E mutation, detected by an FDA-approved test, after prior therapy, based on the BEACON CRC trial. However, first line treatment options for this group of patients remains an unmet need.

BREAKWATER is an ongoing, active-controlled, open-label, multicenter, randomized, Phase 3 study in which first line Encorafenib plus Cetuximab plus or minus chemotherapy was compared with Standard of Care chemotherapy alone, in patients with BRAF V600E-mutant mCRC. In this trial, patients were initially randomly assigned 1:1:1 to receive either Encorafenib orally once daily with Cetuximab IV infusion every 2 weeks (Encorafenib plus Cetuximab arm), Encorafenib orally once daily with Cetuximab IV infusion every 2 weeks and mFOLFOX6 every 2 weeks (Encorafenib plus Cetuximab plus mFOLFOX6 arm), or control group patients who received mFOLFOX6 (Leucovorin, Fluorouracil and Oxaliplatin) or FOLFOXIRI (Leucovorin, Fluorouracil, Oxaliplatin, and Irinotecan), both every 2 weeks, or Capecitabine plus Oxaliplatin (every 3 weeks), each with or without Bevacizumab . The trial was subsequently amended to limit randomization and compare the Encorafenib plus Cetuximab plus mFOLFOX6 group and the control group. Treatment in both groups continued until disease progression, unacceptable toxicity. The Primary endpoint was Progression Free Survival (PFS) and Objective Response Rate (ORR) and Secondary endpoints included Duration of Response, Overall survival, Time to Response and patient Reported Outcomes.

The present FDA accelerated approval was based on the results of the Encorafenib plus Cetuximab plus mFOLFOX6 group, compared to the control group. The major efficacy outcome measure was confirmed ORR assessed by Blinded Independent Central Review and evaluated in the first 110 patients randomly assigned in each treatment group. The ORR was 61% in the Encorafenib plus Cetuximab plus mFOLFOX6 group compared to 40% in the control group. Median Duration of Response was 13.9 months and 11.1 months in the two groups respectively. PFS and OS data in this ongoing trial are immature. The most common grade 3 or 4 laboratory abnormalities were increased lipase and decreased neutrophil count.

In conclusion, a combination of Encorafenib and Cetuximab plus mFOLFOX6 resulted in a statistically significant and clinically meaningful improvement in Response Rate and Durability of Response in treatment-naïve metastatic CRC patients with a BRAF V600E mutation. Continued approval for this indication is contingent upon verification of clinical benefit.

https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-encorafenib-cetuximab-and-mfolfox6-metastatic-colorectal-cancer-braf

Defining durability with AUGTYRO® (repotrectinib), the next-generation TKI for ROS1+ NSCLC

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Expert opinion: Jyoti Malhotra, MD, MPH
Content sponsored by: Bristol Myers Squibb
Dr. Malhotra was compensated by BMS for her contributions to this article.

Introduction: Unmet need in ROS1+ NSCLC
The identification of ROS1 as a therapeutic target in NSCLC has led to the development and approval of several first-generation TKIs.3-5 Despite this, the median duration of response is ~2 years with these first-generation TKIs.6,7 A different approach is needed.

1L AUGTYRO in locally advanced or metastatic ROS1+ NSCLC
TRIDENT-1, a global, phase 1/2, single-arm, multicohort, open-label trial, led to the approval of AUGTYRO as a treatment option in adult patients for locally advanced or metastatic ROS1+ NSCLC.1,2,8 AUGTYRO is the first and only approved next-generation TKI for this indication.8,9 “This approval has made it possible for newly diagnosed patients to have access to [another] treatment option that may provide disease control,” stated Dr. Malhotra.

                                               TRIDENT-1 Trial Design1,3,10,11In TRIDENT-1, the phase 2 dose expansion cohort included 127 patients who were either TKI-naïve (n=71) or had received a TKI (n=56).2 The primary endpoint was ORR and some of the secondary efficacy outcome measures were DOR and intracranial response. Baseline characteristics were reported for patients who had and had not received a prior TKI.2

There are warnings and precautions associated with AUGTYRO to keep in mind. These include central nervous system adverse reactions, interstitial lung disease (ILD)/pneumonitis, hepatotoxicity, myalgia with creatinine phosphokinase (CPK) elevation, hyperuricemia, skeletal fractures, and embryo-fetal toxicity.1 Additional information related to warnings and precautions can be found here.

In the primary analysis, efficacy results for the TKI-naïve population (n=71) treated with AUGTYRO were as follows12:

  • ORR of 79% ([95% CI: 68–88]; median follow-up for ORR data: 18.1 months)
    • CR of 6% (n=4)
    • PR of 73% (n=52)
  • mDOR of 34 months ([95% CI: 25.6–NE]; range: 1.4+ to 42.4+ months; median follow-up for DOR data: 24.0 months)1,10
  • icORR observed in 7/8 patients with measurable baseline brain metastasis (median follow-up for icORR data: 18.1 months)1,12

                         Change in tumor burden by BICR in the TKI-naïve population12*

                           *Three patients discontinued study treatment before completing any post-baseline scans.12

In a follow-up analysis, continued response to treatment was seen with AUGTYRO. At the 33.9-month median follow-up, efficacy results for the TKI-naïve population treated with AUGTYRO were as follows9:
• cORR of 79% (n=71; [95% CI: 68–88])
• mDOR of 34.1 months (n=71; [95% CI: 27.4–NE])
• icORR of 89% (n=9; [95% Cl: 52–100]) in patients with measurable baseline brain metastasis

“TRIDENT-1 demonstrated an ORR of 79%, but more notably, a long mDOR of 34 months—this is almost 3 years,” explained Dr. Malhotra.

In TRIDENT-1, the most common reactions reported in ≥20% of 426 patients treated with AUGTYRO at the recommended dose were dizziness, dysgeusia, peripheral neuropathy, constipation, dyspnea, fatigue, ataxia, cognitive impairment, muscular weakness, and cognitive impairment.1 AUGTYRO was discontinued in 7% of patients, interrupted in 50% of patients, and dosage was reduced in 38% of patients due to adverse reactions.1 Serious adverse reactions occurred in 35% of patients receiving AUGTYRO. The most frequent (≥2%) serious adverse reactions were pneumonia, dyspnea, pleural effusion, and hypoxia. Fatal adverse reactions occurred in 3.5% of patients and included pneumonia, pneumonia aspiration, cardiac arrest, sudden cardiac death, cardiac failure, hypoxia, dyspnea, respiratory failure, tremor, and disseminated intravascular coagulation.1

AUGTYRO is a next-generation ROS1 TKI with a compact structure that is smaller than currently available ROS1 TKIs.1,13,14
• Potential to decrease the development of ROS1 resistance mutations
• Potential to circumvent known ROS1 resistance mutations
• Physiochemical parameters for enhanced intracranial activity

                                    Mechanism of Action1,13


Dosing of AUGTYRO
The recommended oral dose of AUGTYRO is1:
• 160 mg (4x 40-mg capsules, or a single 160-mg capsule, QD) for the first 14 days
• 160 mg (4x 40-mg capsules, or a single 160-mg capsule, BID) on Day 15 and onward, until disease progression or unacceptable toxicity

“More recently, the 160 mg tablet is also available for use, which is great because now patients only need to take one tablet,” stated Dr. Malhotra. AUGTYRO can be taken with or without food.1 Patients should be advised not to drink grapefruit juice or eat grapefruit while taking AUGTYRO.1 Capsules should be swallowed whole at approximately the same time every day as prescribed.1 Contents of the capsule should not be opened, crushed, chewed, or dissolved.1 If a dose is missed or if a patient vomits at any time after taking a dose, instruct patients to skip the dose and resume at a regularly scheduled time.1 Two doses should not be taken at the same time.1 Adjustable dosing allows for dose modification if needed for adverse reactions. Recommended dosage reductions for adverse reactions are the following1:

  • For the dose of 160 mg QD:
    • First dose reduction: 120 mg QD
    • Second dose reduction: 80 mg QD
  • For the dose of 160 mg BID:
    • First dose reduction: 120 mg BID
    • Second dose reduction: 80 mg BID

A prescription for 40-mg capsules is required for dose reductions.1 Additional detailed dose reduction recommendations are available for key adverse reactions.1

Summary and conclusions
AUGTYRO is the next-generation TKI helping patients with ROS1+ NSCLC start strong.1,2,9 Results from the TRIDENT-1 trial and continued response for TKI-naïve patients at the ~3-year follow-up analysis support its current place in therapy.1,2,9 “AUGTYRO is definitely my preferred drug for 1L ROS1+ NSCLC treatment—we are seeing responses for years,” stated Dr. Malhotra.

1L=first line; ATP=adenosine triphosphate; BICR=blinded independent central review; BID=twice daily; CI=confidence interval; CNS=central nervous system; cORR=confirmed ORR; CR=complete response; DOR=duration of response; ECOG PS=Eastern Cooperative Oncology Group performance status; EXP=expansion cohort; icORR=intracranial ORR; mDOR=median DOR; mNSCLC=metastatic NSCLC; NE=not evaluable; NSCLC=non-small cell lung cancer; ORR=overall response rate; PFS=progression-free survival; PR=partial response; QD=everyday; QTc=corrected QT; RECIST=Response Evaluation Criteria in Solid Tumors; ROS1=ROS proto oncogene 1; RP2D=recommended phase 2 dose; TKI=tyrosine kinase inhibitor.

INDICATION
AUGTYRO® (repotrectinib) is indicated for the treatment of adult patients with locally advanced or metastatic ROS1-positive non-small cell lung cancer (NSCLC).

IMPORTANT SAFETY INFORMATION
Warnings & Precautions
Central Nervous System Adverse Reactions
• Among the 426 patients who received AUGTYRO in Study TRIDENT-1, a broad spectrum of central nervous system (CNS) adverse reactions including dizziness, ataxia, and cognitive disorders occurred in 77% of patients with Grade 3 or 4 events occurring in 4.5%.
• Dizziness, including vertigo, occurred in 65%; Grade 3 dizziness occurred in 2.8% of patients. The median time to onset was 7 days (1 day to 1.4 years). Dose interruption was required in 9% of patients, and 11% required dose reduction of AUGTYRO due to dizziness.
• Ataxia, including gait disturbance and balance disorder, occurred in 28% of patients; Grade 3 ataxia occurred in 0.5%. The median time to onset was 15 days (1 day to 1.4 years). Dose interruption was required in 5% of patients, 8% required dose reduction and one patient (0.2%) permanently discontinued AUGTYRO due to ataxia.
• Cognitive impairment, including memory impairment and disturbance in attention, occurred in 25% of patients. Cognitive impairment included memory impairment (15%), disturbance in attention (12%), and confusional state (2%); Grade 3 cognitive impairment occurred in 0.9% of patients. The median time to onset of cognitive disorders was 37 days (1 day to 1.4 years). Dose interruption was required in 2% of patients, 2.1% required dose reduction and 0.5% permanently discontinued AUGTYRO due to cognitive adverse reactions.
• Mood disorders occurred in 6% of patients. Mood disorders occurring in >1% of patients included anxiety (2.6%); Grade 4 mood disorders (mania) occurred in 0.2% of patients. Dose interruption was required in 0.2% of patients and 0.2% required a dose reduction due to mood disorders.
• Sleep disorders including insomnia and hypersomnia occurred in 18% of patients. Sleep disorders observed in >1% of patients were somnolence (9%), insomnia (6%) and hypersomnia (1.6%). Dose interruption was required in 0.7% of patients, and 0.2% required a dose reduction due to sleep disorders.
• The incidences of CNS adverse reactions reported were similar in patients with and without CNS metastases.
• Advise patients not to drive or use machines if they are experiencing CNS adverse reactions. Withhold and then resume at same or reduced dose upon improvement, or permanently discontinue AUGTYRO based on severity.
Interstitial Lung Disease (ILD)/Pneumonitis
• Among the 426 patients treated with AUGTYRO, ILD/pneumonitis (pneumonitis [2.8%] and ILD [0.2%]) occurred in 3.1%; Grade 3 ILD/pneumonitis occurred in 1.2%. The median time to onset was 45 days (19 days to 0.9 years). Dose interruption was required in 1.4% of patients, 0.5% required dose reduction, and 1.1% permanently discontinued AUGTYRO due to ILD/pneumonitis.
• Monitor patients for new or worsening pulmonary symptoms indicative of ILD/pneumonitis. Immediately withhold AUGTYRO in patients with suspected ILD/pneumonitis and permanently discontinue AUGTYRO if ILD/pneumonitis is confirmed.
Hepatotoxicity
• Among the 426 patients treated with AUGTYRO, increased alanine transaminase (ALT) occurred in 38%, increased aspartate aminotransferase (AST) occurred in 41%, including Grade 3 or 4 increased ALT in 3.3% and increased AST in 2.9%. The median time to onset of increased ALT or AST was 15 days (range: 1 day to 1.9 years). Increased ALT or AST leading to dose interruptions or reductions occurred in 2.8% and 1.2% of patients, respectively. Hyperbilirubinemia leading to dose interruptions occurred in 0.5%.
• Monitor liver function tests, including ALT, AST and bilirubin, every 2 weeks during the first month of treatment, then monthly thereafter and then as clinically indicated. Withhold and then resume at same or reduced dose upon improvement or permanently discontinue AUGTYRO based on the severity.
Myalgia with Creatine Phosphokinase (CPK) Elevation
• AUGTYRO can cause myalgia with or without creatine phosphokinase (CPK) elevation. Among the 426 patients treated with AUGTYRO, myalgia occurred in 13% of patients, with Grade 3 in 0.7%. Median time to onset of myalgia was 19 days (range: 1 day to 2 years). Concurrent increased CPK within a 7-day window was observed in 3.7% of patients. AUGTYRO was interrupted in one patient with myalgia and concurrent CPK elevation.
• Advise patients to report any unexplained muscle pain, tenderness, or weakness. Monitor serum CPK levels during AUGTYRO treatment and monitor CPK levels every 2 weeks during the first month of treatment and as needed in patients reporting unexplained muscle pain, tenderness, or weakness. Initiate supportive care as clinically indicated. Based on severity, withhold and then resume AUGTYRO at same or reduced dose upon improvement.
Hyperuricemia
• Among the 426 patients treated with AUGTYRO, 21 patients (5%) experienced hyperuricemia reported as an adverse reaction, 0.7% experienced Grade 3 or 4 hyperuricemia. One patient without pre-existing gout required urate-lowering medication.
• Monitor serum uric acid levels prior to initiating AUGTYRO and periodically during treatment. Initiate treatment with urate-lowering medications as clinically indicated. Withhold and then resume at same or reduced dose upon improvement, or permanently discontinue AUGTYRO based on severity.
Skeletal Fractures
• Among 426 adult patients who received AUGTYRO, fractures occurred in 2.3%. Fractures involved the ribs (0.5%), feet (0.5%), spine (0.2%), acetabulum (0.2%), sternum (0.2%), and ankles (0.2%). Some fractures occurred at sites of disease and prior radiation therapy. The median time to fracture was 71 days (range: 31 days to 1.4 years). AUGTYRO was interrupted in 0.3% of patients.
• Of 26 evaluable patients in an ongoing open-label study in pediatric patients, fractures occurred in one 12-year-old patient (ankle/foot) and one 10-year-old patient (stress fracture). AUGTYRO was interrupted in both patients. AUGTYRO is not approved for use in pediatric patients less than 12 years of age.
• Promptly evaluate patients with signs or symptoms (e.g., pain, changes in mobility, deformity) of fractures. There are no data on the effects of AUGTYRO on healing of known fractures and risk of future fractures.
Embryo-Fetal Toxicity
• Based on literature reports in humans with congenital mutations leading to changes in tropomyosin receptor tyrosine kinase (TRK) signaling, findings from animal studies, and its mechanism of action, AUGTYRO can cause fetal harm when administered to a pregnant woman.
• Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective non-hormonal contraception during treatment with AUGTYRO and for 2 months following the last dose, since AUGTYRO can render some hormonal contraceptives ineffective.
• Advise male patients with female partners of reproductive potential to use effective contraception during treatment with AUGTYRO and for 4 months after the last dose.
Adverse Reactions
• The safety of AUGTYRO was evaluated in 426 patients in TRIDENT-1. The most common adverse reactions (≥20%) were dizziness, dysgeusia, peripheral neuropathy, constipation, dyspnea, fatigue, ataxia, cognitive impairment, muscular weakness, and nausea.
Drug Interactions
Effects of Other Drugs on AUGTYRO
Strong and Moderate CYP3A Inhibitors
• Avoid concomitant use with strong or moderate CYP3A inhibitors. Concomitant use of AUGTYRO with a strong or a moderate CYP3A inhibitor may increase repotrectinib exposure, which may increase the incidence and severity of adverse reactions of AUGTYRO. Discontinue CYP3A inhibitors for 3 to 5 elimination half-lives of the CYP3A inhibitor prior to initiating AUGTYRO.

P-gp Inhibitors
• Avoid concomitant use with P-gp inhibitors. Concomitant use of AUGTYRO with a P-gp inhibitor may increase repotrectinib exposure, which may increase the incidence and severity of adverse reactions of AUGTYRO.
Strong and Moderate CYP3A Inducers
• Avoid concomitant use with strong or moderate CYP3A inducers. Concomitant use of AUGTYRO with a strong or moderate CYP3A inducer may decrease repotrectinib plasma concentrations, which may decrease efficacy of AUGTYRO.
Effects of AUGTYRO on other Drugs
Certain CYP3A4 Substrates
• Avoid concomitant use unless otherwise recommended in the Prescribing Information for CYP3A substrates, where minimal concentration changes can cause reduced efficacy. If concomitant use is unavoidable, increase the CYP3A4 substrate dosage in accordance with approved product labeling.
• Repotrectinib is a CYP3A4 inducer. Concomitant use of repotrectinib decreases the concentration of CYP3A4 substrates, which can reduce the efficacy of these substrates.
Contraceptives
• Repotrectinib is a CYP3A4 inducer, which can decrease progestin or estrogen exposure to an extent that could reduce the effectiveness of hormonal contraceptives.
• Avoid concomitant use of AUGTYRO with hormonal contraceptives. Advise females of childbearing potential to use an effective nonhormonal contraceptive.
Please see US Full Prescribing Information for AUGTYRO.

References:
1. AUGTYRO [package insert]. Princeton, NJ: Bristol-Myers Squibb Company.
2. Drilon A, Camidge DR, Lin JJ, et al. Repotrectinib in ROS1 fusion–positive non–small-cell lung cancer. N Engl J Med. 2024;390(2):118-131.
3. Lin JJ, Shaw AT. Recent advances in targeting ROS1 in lung cancer. J Thorac Oncol. 2017;12(11):1611-1625.
4. Rikova K, Guo A, Zeng Q, et al. Global survey of phosphotyrosine signaling identifies oncogenic kinases in lung cancer. Cell. 2007;131:1190-1203.
5. US Food and Drug Administration. FDA Approves Crizotinib Capsules. Published March 11, 2016. Accessed October 21, 2024. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-crizotinib-capsules.
6. Drilon A, Chiu CH, Fan Y, et al. Long-Term Efficacy and Safety of Entrectinib in ROS1 Fusion-Positive NSCLC. JTO Clin Res Rep. 2022;3(6):100332. Published 2022 Apr 29. doi:10.1016/j.jtocrr.2022.100332.
7. Shaw AT, Riely GJ, Bang YJ, et al. Crizotinib in ROS1-rearranged advanced non-small-cell lung cancer (NSCLC): updated results, including overall survival, from PROFILE 1001. Ann Oncol. 2019;30(7):1121-1126. doi:10.1093/annonc/mdz131.
8. US Food and Drug Administration. Center for Drug Evaluation and Research. AUGTYRO Label and Approval History. NDA218213. Published November 15, 2023. Accessed October 16, 2024. https://www.accessdata.fda.gov/drugsatfda_docs/appletter/2023/218213Orig1s000ltr.pdf.
9. Drilon A, Dziadziuszko R, Camidge DR, et al. Repotrectinib in tyrosine kinase inhibitor (TKI)-naïve patients with advanced ROS1 fusion-positive (ROS1+) NSCLC in the phase 1/2 TRIDENT-1 trial: clinical update, treatment beyond progression and subsequent therapies. Oral presentation at ASCO 2024. Poster 386.
10. Cho BC, Camidge DR, Lin JJ, et al. Repotrectinib in patients with ROS1 fusion-positive non-small cell lung cancer: update from the pivotal phase 1/2 TRIDENT-1 trial. Oral presentation at WCLC 2023. Abstract OA03.06.
11. ClinicalTrials.gov. A study of repotrectinib (TPX-0005) in patients with advanced solid tumors harboring ALK, ROS1, or NTRK1-3 rearrangements. Accessed April 19, 2024. https://clinicaltrials.gov/study/NCT03093116.
12. Cho BC, Lin JJ, Camidge DR, et al. Pivotal topline data from the phase 1/2 TRIDENT-1 trial of repotrectinib in patients with ROS1+ advanced non-small cell lung cancer (NSCLC). Oral presentation at ENA 2022. Abstract 2LBA.
13. Drilon A, Ou SI, Cho BC, et al. Repotrectinib (TPX-0005) is a next-generation ROS1/TRK/ALK inhibitor that potently inhibits ROS1/TRK/ALK solvent-front mutations. Cancer Discov. 2018;8(10):1227-1236.
14. Murray BW, Rogers E, Zhai D, et al. Molecular Characteristics of Repotrectinib That Enable Potent Inhibition of TRK Fusion Proteins and Resistant Mutations. Mol Cancer Ther. 2021;20(12):2446-2456. doi:10.1158/1535-7163.MCT-21-0632

© 2024 Bristol-Myers Squibb Company. AUGTYRO®, is a registered trademark of
Bristol-Myers Squibb Company.
3600-US-2400322 11/24

ENHERTU® after Endocrine Therapy in Advanced Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. It is estimated that in the US, approximately 310,720 new cases of female breast cancer will be diagnosed in 2024, and about 42,250 individuals will die of the disease, largely due to metastatic recurrence.

The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. Patients with high levels of HER2 expression (IHC 3+ or 2+/FISH+) are classified as HER2-positive. Patients with HER2-positive metastatic breast cancer are often treated with anti-HER2 targeted therapy along with chemotherapy, irrespective of hormone receptor status, and this has resulted in significantly improved treatment outcomes. Tumors that are not classified as HER2-positive are classified as HER2-negative. Despite being classified as HER2-negative, majority these tumors still have some level of HER2 expression.

About 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors, and Hormone Receptor (HR)-positive/HER2-negative breast cancer is the most frequently diagnosed molecular subtype. It is estimated that approximately 60-65% of HR-positive/HER2-negative breast cancers are HER2-low and potentially an additional 25% may be HER2-ultralow. These patients are often treated with single agent endocrine therapy, endocrine therapy in combination with CDK4/6 inhibitor, or chemotherapy. Resistance to hormonal therapy occurs in a majority of the patients and there is therefore an unmet need for agents with novel mechanisms of action. Further, there are no targeted therapies specifically approved for patients with HER2-low or HER2-ultralow expression, prior to chemotherapy.

ENHERTU® (Trastuzumab Deruxtecan) is an Antibody-Drug Conjugate (ADC) composed of a humanized monoclonal antibody specifically targeting HER2, with the amino acid sequence similar to Trastuzumab, a cleavable tetrapeptide-based linker, and a potent cytotoxic Topoisomerase I inhibitor as the cytotoxic drug (payload). ENHERTU® has a favorable pharmacokinetic profile and the tetrapeptide-based linker is stable in the plasma and is selectively cleaved by cathepsins that are up-regulated in tumor cells. Unlike KADCYLA® (ado-Trastuzumab emtansine), another ADC targeting HER2, ENHERTU® has a higher drug-to-antibody ratio (8 versus 4), released payload easily crosses the cell membrane with resulting potent cytotoxic effect on neighboring tumor cells regardless of target expression, and the released cytotoxic agent (payload) has a short half-life, thus minimizing systemic exposure.

DESTINY-Breast06 is a global, randomized, open-label Phase III trial evaluating the efficacy and safety of ENHERTU® versus chemotherapy in patients with HR-positive, HER2-low, or HER2-ultralow advanced or metastatic breast cancer. This study enrolled 866 patients (N=713 for HER2-low and N=153 for HER2-ultralow). HER2-low was defined as IHC 1+ or 2+ or FISH negative and HER2-ultralow was defined as IHC 0 with membrane staining. Patients were randomized 1:1 to receive ENHERTU® 5.4 mg/kg every 3 weeks (N=436) or physicians choice of chemotherapy which included Capecitabine, Paclitaxel, or nab-Paclitaxel (N=430). Patients in the trial had no prior chemotherapy for advanced or metastatic disease and received at least two lines of prior endocrine therapy in the metastatic setting. Patients were also eligible if they had received one prior line of endocrine therapy combined with a CDK4/6 inhibitor in the metastatic setting and experienced disease progression within six months of starting 1st-line treatment, or received endocrine therapy as an adjuvant treatment and experienced disease recurrence within 24 months. Patients were stratified based on prior CDK4/6 inhibitor use, HER2 expression and prior taxane use in the non-metastatic setting. Patients in the trial had received a median of two prior lines of endocrine therapy. In the overall trial population, 14.9% of patients in the ENHERTU® group and 19.2% in the chemotherapy group had received one prior line of endocrine therapy. No patients had received prior chemotherapy for metastatic disease. The Primary endpoint was Progression Free Survival (PFS) in the HER2-low patient population as measured by Blinded Independent Central Review (BICR). Key Secondary endpoints included Progression Free Survival (PFS) in the overall trial population (HER2-low and HER2-ultralow), Overall survival (OS) in the HER2-low patient population, Objective Response Rate (ORR), Duration of response (DOR) and Safety. The median duration of follow-up was 18.2 months.

In the primary analysis of this study, results showed that in the HER2-low expression patients, ENHERTU® reduced the risk of disease progression or death by 38%, with a median PFS was 13.2 months in the ENHERTU® group, compared to 8.1 months for chemotherapy (HR=0.62; P<0.0001). For the overall trial population (HER2-low and HER2-ultralow), the median PFS results were similar and the median PFS was 13.2 months for ENHERTU® versus 8.1 months for chemotherapy (HR=0.63; P<0.0001). ENHERTU® reduced the risk of disease progression or death by 37% compared to chemotherapy.

A prespecified exploratory analysis showed that the improvement in PFS was consistent between patients with HER2-low and HER2-ultralow expression. In patients with HER2-ultralow expression, ENHERTU® reduced the risk of disease progression or death by 22% compared to chemotherapy, with a median PFS of 13.2 months versus 8.3 months, respectively (HR=0.78).

The Objective Response Rate (ORR) in HER2-Low Population was 56.5% for ENHERTU® compared to 32.2% for chemotherapy, in the Overall Trial Population was 57.3% for ENHERTU® versus 31.2% for chemotherapy, and in the HER2-Ultralow Subgroup was 61.8% for ENHERTU® versus 26.3% for chemotherapy. The median duration of response across these three groups was 14.3 months.

The safety profile of ENHERTU® was consistent with previous breast cancer clinical trials and no new safety concerns identified. The most common Grade 3 or higher treatment-related adverse events occurring in 5% or more of patients treated with ENHERTU® were neutropenia (20.7%) and anemia (5.8%). Interstitial Lung Disease (ILD), adjudicated as drug-related by an independent committee, occurred in 11.3% of patients treated with ENHERTU®. The majority of ILD events were low grade.

The results from the DESTINY-Breast06 trial underscore the significant clinical benefits of ENHERTU® in improving PFS and ORR in patients with HR-positive, HER2-low, and HER2-ultralow metastatic breast cancer, offering a promising alternative to standard chemotherapy. These findings highlight the potential of ENHERTU® to become a new standard of care for this patient population, pending further investigation and regulatory approval. The detailed positive outcomes underscore the clinical benefits and reinforce the promise of ENHERTU® in treating this challenging cancer subtype.

Trastuzumab Deruxtecan after Endocrine Therapy in Metastatic Breast Cancer. Bardia A, Hu X, Dent R, et al. for the DESTINY-Breast06 Trial Investigators. N Engl J Med 2024;391:2110-2122. DOI: 10.1056/NEJMoa2407086.

RYBREVANT® plus LAZCLUZE® versus TAGRISSO® in Previously Untreated EGFR-Mutated Advanced NSCLC

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histological subtype of lung cancer. Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR mutations, and 90% of these mutations are either exon 19 deletions or L858R substitution mutation in exon 21.

Epidermal Growth Factor Receptor (EGFR) plays an important role in regulating cell proliferation, survival and differentiation, and is overexpressed in a variety of epithelial malignancies. EGFR targeted Tyrosine Kinase Inhibitors (TKIs) such as Gefitinib, Erlotinib, Afatinib, Dacomitinib and Osimertinib (TAGRISSO®) target the EGFR signaling cascade. However, patients eventually develop drug resistance due to new EGFR mutations. Another important cause of drug resistance to TKIs is due to the activation of parallel RTK (Receptor Tyrosine Kinase) pathways such as Hepatocyte Growth Factor/Mesenchymal-Epithelial Transition factor (HGF/MET) pathway, thereby bypassing EGFR TKI inhibitors. These patients are often treated with platinum-based chemotherapy as the next line of therapy, resulting in a median Progression Free Survival of about 5 months.

Amivantamab (RYBREVANT®) is a fully human bispecific antibody directed against EGFR and MET receptors. Amivantamab binds extracellularly and simultaneously blocks ligand-induced phosphorylation of EGFR and c-MET, inhibiting tumor growth and promoting tumor cell death. Further, Amivantamab down regulates receptor expression on tumor cells thus preventing drug resistance mediated by new emerging mutations of EGFR or c-MET. By binding to the extracellular domain of the receptor protein, Amivantamab can bypass primary and secondary TKI resistance at the active site. Amivantamab also engages effector cells such as Natural Killer cells, monocytes, and macrophages via its optimized Fc domain. Amivantamab demonstrated activity against a wide range of activating and resistance mutations in EGFR-mutated NSCLC, and in patients with MET exon 14 skip mutations, and is approved for the treatment of patients with EGFR exon 20 insertion mutations, whose disease progressed on or after platinum-based chemotherapy.

Lazertinib (LAZCLUZE®) is a highly selective, third-generation TKI that penetrates the CNS, with demonstrated efficacy in activating EGFR mutations and acquired T790M “gatekeeper” point mutation. Combining Amivantamab with Lazertinib has been shown to provide a synergistic benefit by targeting the extracellular and catalytic EGFR domains. The combination of Amivantamab plus Lazertinib has shown clinically meaningful and durable antitumor activity in patients with previously untreated or Osimertinib-pretreated EGFR –mutated advanced NSCLC, with clinical activity against a broad spectrum of secondary EGFR and MET molecular alterations and even in tumors of patients without an identified resistance mechanism.

The MARIPOSA trial is an international, randomized Phase 3 study, conducted to assess the efficacy and safety of a combination of Amivantamab and Lazertinib as compared with Osimertinib alone, as first-line treatment in patients with EGFR-mutated advanced NSCLC. In this study, a third arm evaluated Lazertinib monotherapy, to dissect the individual contributions of each component in the combination. This study included 1074 patients (N=1074) with untreated EGFR-mutated advanced NSCLC who were randomly assigned in a 2:2:1 ratio to receive Amivantamab plus Lazertinib (N=429), Osimertinib monotherapy (N=429), or Lazertinib monotherapy (N=216). Amivantamab was administered weekly at a dose of 1050 mg IV (or 1400 mg IV in patients with a body weight of 80 kg or more) for the first 4 weeks (cycle 1), with the first infusion split over a period of 2 days (with 350 mg given on cycle 1, day 1, and the remainder given on cycle 1, day 2). Starting at cycle 2, the same Amivantamab dose was administered every 2 weeks. Osimertinib 80 mg and Lazertinib 240 mg were taken orally daily. The median age was 63 years, majority of patients were Asian women or White and had never smoked. Approximately 60% had EGFR exon 19 deletions and 40% had exon 21 L858R mutations. Randomization was stratified according to EGFR mutation type (ex19del or L858R), Asian race (yes or no), and history of brain metastases (yes or no). The Primary end point was Progression-Free Survival (PFS) in the Amivantamab plus Lazertinib group as compared with the Osimertinib group, as assessed by Blinded Independent Central Review. Secondary end points included Overall Survival (OS), Objective Response (defined as a Complete or Partial Response), Duration of Response, and Safety.

The median PFS was significantly longer in the Amivantamab plus Lazertinib group at 23.7 months compared to 16.6 months in the Osimertinib group ((HR for progression or death = 0.70; P<0.001). The Objective Response was 86% in the Amivantamab plus Lazertinib group and 85% in the Osimertinib group. Among patients with a confirmed response (336 in the Amivantamab plus Lazertinib group and 314 in the Osimertinib group), the median response duration was 25.8 months and 16.8 months, respectively. In a planned interim Overall Survival analysis, Hazard Ratio for death with Amivantamab plus Lazertinib was 0.80 (95% CI, 0.61–1.05).

EGFR and MET-related toxic effects were the most common side effects and most adverse events were of grade 1 or 2. The treatment discontinuation due to adverse events occurred in 10% of patients in the Amivantamab plus Lazertinib group versus 3% in the Osimertinib group. The incidence of venous thromboembolic adverse events was higher with Amivantamab Plus Lazertinib than with Osimertinib and most of the thromboembolic events in the Amivantamab plus Lazertinib group occurred during the first 4 months of treatment. This has been attributed to a transitory prothrombotic state caused by a mechanism of rapid tumor-cell death by the Amivantamab plus Lazertinib combination.

In conclusion, the combination of Amivantamab plus Lazertinib demonstrated superior efficacy over Osimertinib as a first-line therapy for EGFR-mutated advanced NSCLC, offering longer Progression-Free Survival and Duration of Response.

Amivantamab plus Lazertinib in Previously Untreated EGFR-Mutated Advanced NSCLC. Cho BC, Lu S, Felip E, et al. for the MARIPOSA Investigators. N Engl J Med 2024;391:1486-1498.

TAGRISSO® after Chemoradiotherapy in Stage III EGFR-Mutated NSCLC

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SUMMARY: The FDA on September 25, 2024, approved Osimertinib (TAGRISSO®) for adult patients with locally advanced, unresectable (Stage III) Non-Small Cell Lung Cancer (NSCLC) whose disease has not progressed during or following concurrent or sequential platinum-based chemoradiation therapy and whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Approximately one third of all patients with NSCLC have Stage III, locally advanced disease at the time of initial presentation and 60 to 90% of these patients have unresectable disease. These patients are treated with concurrent chemoradiotherapy (CRT) followed by consolidation therapy with Durvalumab (IMFINZI®) in patients without progression, as this regimen confers an Overall Survival advantage, and is considered the standard of care (PACIFIC trial).

EGFR (Epidermal Growth Factor Receptor) mutations are found in up to one third of patients with unresectable Stage III NSCLC. There are currently no approved targeted treatments for patients with unresectable Stage III EGFR-mutated NSCLC. The current standard of care, which includes consolidation therapy with Durvalumab, may not offer clear benefits to this subset of patients with EGFR mutations.

Osimertinib (TAGRISSO®) is a highly selective third-generation, irreversible Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (TKI), presently approved by the FDA, for the first-line treatment of patients with metastatic NSCLC, whose tumors have Exon 19 deletions or Exon 21 L858R mutations, as well as treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, whose disease has progressed on or after EGFR-TKI therapy. Osimertinib is also approved by the FDA as adjuvant treatment for resected Stage IB–IIIA EGFR-mutated NSCLC. Further, Osimertinib has higher CNS penetration and is therefore able to induce responses in 70-90% of patients with brain metastases.

LAURA was a global, randomized, double-blind, placebo-controlled, multicenter Phase III trial conducted to assess the efficacy and safety of Osimertinib in patients with unresectable Stage III NSCLC harboring EGFR mutations (EGFR exon 19 deletion or exon 21 L858R mutation). The trial enrolled patients who had not experienced disease progression during or after definitive platinum-based chemoradiotherapy (CRT). A total of 216 patients who had undergone CRT were randomly assigned 2:1 to receive Osimertinib 80 mg orally once daily (N=143) or placebo once per day (N=73). Treatment was continued until Blinded Independent Central Review (BICR)–assessed disease progression, unacceptable toxicity, or other discontinuation criteria were met. Upon disease progression, patients in the placebo arm were permitted to receive Osimertinib, allowing for crossover therapy. Stratification factors included method of CRT (concurrent versus sequential) and disease Stage (IIIA versus IIIB/C). Both treatment groups were well balanced. The median patient age was 63 years, approximately 60% of participants were female, 83% were Asian, 69% had never smoked and 85% had Stage IIIA and B disease. Majority of patients received concurrent CRT rather than sequential CRT. The Primary end point was Progression Free Survival (PFS) as assessed by BICR. Key Secondary end points included Overall Survival (OS), survival without progression of CNS disease (CNS Progression Free Survival), Objective Response Rate (ORR), Duration of Response, Quality of Life, and Safety.

Treatment with Osimertinib resulted in significant PFS improvement compared to placebo. The median PFS was 39.1 months in the Osimertinib group versus 5.6 months in the placebo group, representing an 84% reduction in the risk of disease progression or death (HR=0.16; P<0.001). Additionally, a higher percentage of patients in the Osimertinib group remained alive and progression-free at 12 months compared to the placebo group (74% versus 22% respectively). Subgroup analyses were conducted to evaluate the consistency of treatment effects across various demographic and clinical factors. The benefits of Osimertinib were observed across all prespecified subgroups, indicating a consistent treatment effect, regardless of patient characteristics. The incidence of new lesions was lower with Osimertinib compared to placebo (22% versus 68%), and this included new brain lesions (8% versus 29%) and new lung lesions (6% versus 29%) respectively. The Objective Response Rate was higher with Osimertinib than with placebo (57% versus 33%). The median Duration of Response was longer with Osimertinib (36.9 months) than with placebo (6.5 months). Interim OS data showed a favorable trend for Osimertinib, although maturity was limited at the time of analysis. Further follow-up will be conducted to assess OS as a secondary endpoint. The adverse event profile of Osimertinib was generally consistent with previous studies. Grade 3 or higher adverse events occurred more frequently in the Osimertinib group, with radiation pneumonitis being the most common. However, no new safety concerns emerged during the trial.

In summary, treatment with Osimertinib resulted in significantly longer Progression Free Survival than placebo in patients with unresectable Stage III EGFR-mutated NSCLC following definitive CRT, and should be considered the new standard of care for this group of patients. Overall, the LAURA study represents a major breakthrough in the treatment of EGFR-mutated Stage III NSCLC, addressing an unmet need for targeted therapies in this setting. Further follow-up will provide additional insights into the long-term efficacy and safety of Osimertinib in this patient population.

Osimertinib after Chemoradiotherapy in Stage III EGFR-Mutated NSCLC. Lu S, Kato T, Dong X, et al. for the LAURA Trial Investigators. N Engl J Med. 2024;391:585-597.